How does one launch unmanned high-altitude balloons without posing a safety risk to aviation?

Unmanned balloons can indeed create a safety risk for aircraft. An aircraft could collide with the balloon itself (as described in the case that Jan Hudec posted in his comment), or with the balloon's payload (see the FAA's AIM section 7-5-4 for general comments on this).

But it's important to note that unmanned balloons are (or should be) launched only after appropriate preparation and communication; most countries have some sort of regulations to follow. In the US (for example), 14 CFR 101 governs unmanned balloon launches and it includes the following requirements:

Launches must be in (mostly) clear skies and away from airports and built-up areas
The balloon must have a radar reflector and lights (if launched at night)
ATC must be informed in advance of the balloon launch, expected path etc.
The operator must track the balloon's position and descent and report them to ATC as needed

In other words, the balloon should be as visible as possible - both visually and on radar - and ATC should know where it is. That gives pilots a way to see and avoid the balloon and ATC can provide warnings and/or avoidance instructions to aircraft directly where possible, which is actually fairly similar to how aircraft avoid other aircraft.

Of course, there may be cases where someone launches a balloon without following those rules (or the local equivalents in another country). That would create a much higher safety risk but it would be illegal and the operator would be risking penalties for doing it.


It does, but there is much less of it on the fuselage than on the wing.

There are two ways how ice is accumulated on the aircraft's structure:

When flying through air containing supercooled water droplets, the water will freeze on impact. It does not make much of a difference whether the water impacts the fuselage nose or the leading edge of the wings and tail surfaces: It will form a sheet of clear ice.
When flying through moist air at a temperature close to freezing, the pressure loss of the air flowing around any obstacle will cool it down, so the moisture condenses and, if temperature allows, will form ice accumulations. Those in turn exacerbate the suction peaks, leading to more ice being collected.

The wing's leading edge shows the most pronounced suction peaks, so they will collect most ice. However, if the icing conditions are right, the fuselage nose will also pick up it's share of ice. Along the length of the fuselage, pressure is similar to ambient, so it will collect ice only when sitting on the ground in freezing rain.

Iced engine nacelle in the NASA Lewis (now Glenn) Research Center icing research tunnel (picture source). Here, water is sprayed into the tunnel and forms supercooled droplets.

In both cases icing has nothing to do with the boundary layer - with supercooled water it is simple ballistics, while the second case of ice accumulation is dominated by the pressure of the flow around the aircraft.


Where to get information on FAA AIXM 5.0 versions of Special Activity Airpace (SAA) files?

One possibility is to contact the FAA National Flight Data Center (NFDC). They provide information as part of the US Aeronautical Information Services (AIS).

NFDC Support Desk email is available on this login page, below the login data boxes.

See also this question: Where to find a waypoints/fixed points, navaids, airports database for other aeronautical data sets in case you need them too.


What is the longest range single-pilot certified (FAA and/or EASA) business jet?

There aren't any civilian, current-production jets that come close to the range of the SJ30 for single pilot operations based on my research, although one or two turboprops have comparable ranges. I consulted Aviation Week's "Business Airplane's 2012" and the only other light jets listed with a long range are the Embraer Phenom 300 with a range of 1,954 nm, and the Cessna Citation CJ4 with a range of 1,913 nm.  The Cessna CJ3 comes in at a respectable 1,869 nm. The PC-24, which is still undergoing certification in 2016, is listed here with an NBAA range of 1,950 nm. All of these are (or will be) single-pilot certified in at least one cockpit configuration, to my knowledge.

Is there any reason you're restricting this to jets and not turboprops? (Speed is one of the biggest differences between the two categories.) The King Air 350IER has a range of 2,239 nm.  Several other turboprops have ranges that are comparable to average light business jets, like the PC-12 NG which has a  range of 1,544 nm.

Here's a graph of my own making to show these statistics:

For any readers unfamiliar with the restrictions regarding FAA approval for single-pilot operations, here's a good source: http://www.flyingmag.com/single-pilot-jets . The biggest stipulation is that transport category aircraft (12,500+ lb MTOW or not commuter category) are assumed to be two-pilot aircraft.

Note:  all ranges listed here except the PC-24's range are NBAA IFR max fuel ranges w/ 100 nm alternate as listed in Aviation Week's "Business Airplanes 2012"


The regulations for this are in 14 CFR 121 Subpart R—FLIGHT TIME LIMITATIONS: FLAG OPERATIONS.

In short, flight time limits within a rolling 24 hour period depend on the number of crew members assigned to the flight:

One or two pilot crews - 8 hours max
Two pilots and one additional flight crewmember: 12 hours max
Three or more pilots and an additional flight crewmember: More than 12 hours, but "adequate sleeping quarters on the airplane" will be provided

However, they may also implement a "Fatigue Risk Management System" which allows them to exceed these limits if they are found to be safe and approved by the FAA.  This system would most likely address the number of timezones crossed but is optional.

A particular airlines pilot contract may also have more restrictive limitations (like considering the number of timezones crossed) that are negotiated by the union, but this is not required by the regulations.

  §121.481   Flight time limitations: One or two pilot crews.

  (a) A certificate holder conducting flag operations may schedule a
  pilot to fly in an airplane that has a crew of one or two pilots for
  eight hours or less during any 24 consecutive hours without a rest
  period during these eight hours.

  ...

  §121.483   Flight time limitations: Two pilots and one additional flight crewmember.

  (a) No certificate holder conducting flag operations may schedule a
  pilot to fly, in an airplane that has a crew of two pilots and at
  least one additional flight crewmember, for a total of more than 12
  hours during any 24 consecutive hours.

  ...

  §121.485   Flight time limitations: Three or more pilots and an additional flight crewmember.

  (a) Each certificate holder conducting flag operations shall schedule
  its flight hours to provide adequate rest periods on the ground for
  each pilot who is away from his base and who is a pilot on an airplane
  that has a crew of three or more pilots and an additional flight
  crewmember. It shall also provide adequate sleeping quarters on the
  airplane whenever a pilot is scheduled to fly more than 12 hours
  during any 24 consecutive hours.

  ...

  §121.495   Fatigue risk management system.

  (a) No certificate holder may exceed any provision of this subpart
  unless approved by the FAA under a Fatigue Risk Management System.

  (b) The Fatigue Risk Management System must include:

  (1) A fatigue risk management policy.

  (2) An education and awareness training program.

  (3) A fatigue reporting system.

  (4) A system for monitoring flightcrew fatigue.

  (5) An incident reporting process.

  (6) A performance evaluation.


Was the colliding object in the Guadalajara accident ever identified?

According to Boeing, there was no foreign object involved at all, and the cause of the damage was  an implosion of the radome due to differential pressure, caused by improper installation of a seal:

From AVHerald:

  On May 31st 2019 Boeing reported that a visual inspection of the radome did not show any evidence of a hard or soft body impact, no DNA material was found. Boeing concluded: "The review showed that an interface seal was installed around the entire periphery of the radome with no openings. This configuration lacked the approximately 8 inch opening in the seal along the bottom of the radome interface specified in engineering drawings and the Airplane Maintenance Manual (AMM 53-52-00) radome installation task. This opening in the seal is required to allow the radome area to drain and for equalization of pressure changes across the radome during flight. A review by our engineering team concluded that the lack of this gap likely resulted in differential pressure across the radome during descent which may have contributed to an internal collapse of the radome."


Should you read back the QNH from an ATIS broadcast?

Uk CAA CAP493 Section 3 Chapter 1 Paragraph 11.4 states :

  In the case of a departure ATIS, controllers must obtain a read-back of all relevant altimeter settings contained in the broadcast, unless the setting will also be passed in association with start-up or taxi clearance.

So from the point of view of the controller you are doing a good thing because you are saving him the expense of having to confirm that you have the right QNH on board.


It's been a long time since I did this but here's then general idea.

Work out your requirements.
Thrust, speed (usually cruise speed) and diameter (usually determined by the available space) being the key ones.
Use a piece of software such as this one to optimise other design parameters for your requirements.
You may also consider off-design (non-cruise) performance.

The link above also contains more details about the design process and considerations.


Why does the Las Vegas Airport have three control towers?

One of those is the old tower, built in 1983, and scheduled for demolition.
(in the bottom left of the picture)

The location and height of the old tower created blind spots, which were covered by the much shorter ground control tower attached to the D Gates. (upper right of the picture)

The new tower is in a better location, and tall enough that it doesn't have blind spots.  I couldn't find a reference to if the D-Gate mini-tower will continue, or be demolished.


Is it possible to control the inlet Mach no. of the engine during flight?

The inlets of supersonic aircraft routinely control (reduce) the Mach number of the engine (at compressor inlet) during flight. This is done using either a 2D ramp type inlet (like Concorde) or a center body (like Mig-21).

These inlets convert the incoming supersonic flow to subsonic flow by forming shock waves in the path of the airflow.

Source: sturgeonshouse.ipbhost.com

In subsonic conditions, the inlets perform two functions:

At cruise condition, diffusion of the free-stream flow to the compressor inlet condition.
At takeoff, acceleration of static air to the compressor inlet condition.

So basically, the inlet design can be optimized such that the Mach number is constant (within some variation) over the engine operational range.

In your case, however, I think that it is a simplifying assumption made for the problem.


What are the amber triangles on the ECAM bleed page on an A320?

It refers to the valve controlled by the guarded RAM AIR pushbutton referred to as "emergency RAM air" in the system diagram.
When the triangles (think of them as arrows indicating flow) are white the triangles indicate sufficient flow of air for conditioning/pressurisation.
The normal position of the guarded Ram Air pushbutton is 'off', ie no light illuminated.
In case both packs fail/shutdown, i.e. both the pack valves are closed, the remaining source for getting airflow through this system is the RAM air. If that is not fully open, while the pack valves are both closed there is insufficient airflow and the triangles therefore turn amber.


How does the NATO code name system work, are they just random names, or is there some sort of rule(s)?

From Wiki

  They provide unambiguous and easily understood English words in a
  uniform manner in place of the original designations, which either may
  have been unknown to the Western world at the time or easily confused
  codes.

Much the like the NATO alphabet rules the names but be easy to understand (possibly under multiple speaking accents) and must be non ambiguous.

The following rules are also applied

  Aircraft

  The first letter indicates the type of aircraft, like
  Bear for a bomber aircraft, or Fulcrum for a fighter aircraft.

  F —
  fighter aircraft, also later ground attack aircraft: List of NATO
  reporting names for fighter aircraft

  B — bomber aircraft: List of NATO
  reporting names for bomber aircraft

  C — commercial aircraft and
  airliners, and cargo aircraft: List of NATO reporting names for
  transport aircraft

  H — helicopters: List of NATO reporting names for
  helicopters

  M — Miscellaneous; trainers, reconnaissance, seaplanes,
  tankers, AEW etc.: List of NATO reporting names for miscellaneous
  aircraft

  For fixed-wing aircraft, one syllable names were used for
  propeller-powered craft (turboprops included), while two-syllable
  names indicated jet engines.


As Ron notes in the comments the A300 did not have it and neither did the A310 however the A300-600 and A310 did have electronically augmented controls according to the airbus site.

  One of the A300-600 and A310’s notable innovations had been the
  introduction of electrical signalling on secondary flight controls,
  replacing the web of cables and pulleys tradionally used. Béteille
  wanted to take this evolution further with the next Airbus aircraft –
  to computer-driven digital “fly-by-wire”, in which the deflections of
  the flying control surfaces on the wing and tail are no longer driven
  directly by the pilots’ controls, but by a computer which calculates
  exactly which control surface deflections are needed to make the
  aircraft respond as the pilot wishes.

The A320 on had Fly-By-Wire

There is a nice little video on the same page that has some facts abut Fly-By-Wire tech over the years. A quick history note is applicable here: what we know of today as Airbus had heavy ties to the Concorde program which implemented the first commercially used analog fly by wire system and depending on how you look at it Airbus' first Fly-By-Wire system as well. These engineers who would later go on to work at what is now Airbus and drive the mentality into the designs which is why they have largely chosen it on all their airframes.


Can a missile be fired when a fighter jet is inverted?

The combat advantage of fighters (as opposed to heavier-payload bombers) is their maneuverability, therefore a missile delivery restriction such as g-limit (think Sidewinder heat-seeker in a dogfight) or attitude would unnecessarily restrict their efficacy.

As a Vietnam-era fighter and attack pilot I fired both unguided (aim and shoot rockets) and guided (target lock-on and shoot) missiles, and neither had associated attitude limits. Missiles that fall clear of the weapon station before rocket-motor ignition (such as the TV-guided Walleye or the optically-pilot-guided Bullpup) are obviously restricted from negative g to ensure safe separation from the airplane, i.e., negative g release from an under-wing weapon station would all but guarantee impact with the airplane.


What is the most critical takeoff shear margin condition for a Type IV anti-ice fluid?

Under the following conditions, we can't take off:

Temperature below -10 degrees C, and
Small Hail or ice pellets (i.e. METAR "PL" reported), and
Rotation speed below 115 knots

To operate with PL reported, we have to have Type IV anti-ice applied, and under those conditions of temperature + precip, they (yeah, "they") have determined that you need at least 115 knots to be sure the fluid adequately shears off.  There are various ways to drive an increase to your VR speed; it takes a pretty light 737 to rotate at 115 knots.  Other aircraft, of course, might normally rotate well below that speed.

I suspect that this limitation is probably applicable across the US airline industry, but the charts I have are specific to one carrier, so I won't generalize beyond that.

This (PL, -10C) is the only place in all the de-ice/anti-ice charts that we have this 115 knot limit.  With all other forms of precipitation, we have a holdover time and the requirement to visually check the fluid for failure; if it has failed, then we don't take off but rather go back & get it washed off & re-applied.  In the case of PL, there is neither a visual check nor a holdover time, but an "allowance time" after which you have to assume fluid failure & go back to start over.  (With PL, you can't visually identify fluid failure -- so you have a conservative time, and after that you're just done.) Speculating, I'm assuming that the nature of the ice pellets is such that they can, in sufficiently cold temperatures, generate the conditions where the fluid needs a particular speed to shear off that some of our operations might not reach -- thus the 115 knot limit.  Whatever can happen with the other precip, presumably can't keep the fluid from shearing off at whatever our lowest possible VR might be -- which I don't know offhand.  Again, for aircraft with a slower VR, you might get those sorts of situations with combinations of precip & temperature that we wouldn't worry about.

Not a complete answer to your question, but hopefully this data point may be helpful.


Level flight just means not climbing or descending.  Where the nose is actually pointing is another matter.
The pitch you are seeing is the "deck angle".  Pitch attitude is normally referenced to the longitudinal axis of the fuselage (and normally, the cabin floor or deck) relative to the horizon for the loading and speed you are at.
The deck angle will be the overall AOA of the wing for a given flight condition plus or minus the wing incidence relative to the fuselage. If the incidence is zero, meaning the wing mean chord line is parallel to the fuselage's long axis, and the wing is operating at a 2 degree overall AOA at that altitude and speed, there's your pitch attitude; +2.  I would expect to see at least a deck angle of a couple degrees when flying at 210 kt indicated in a jet, unless the wing had an incidence of several degrees.
Say the Phenom has a wing incidence of about 1 degree, and that the wing is actually working at an overall AOA of 3 degrees at 210kt; the resulting deck angle would also be +2.
In the Citation with the mechanical spherical attitude indicator with Flight Director, you have to allow for the parallax error due to the gap between the indicator and sphere if your sight line is off a bit, and perhaps the Citation II has a higher wing incidence, and along with a lower wing loading cruises with a lower deck angle of 1 degree or less. With a mechanical indicator it'd probably look close enough to 0 degrees to make that conclusion.


Why don't we treat all takeoffs as short field in GA?

Short-field take-off techniques often achieve a shorter ground run by hurting climb performance. While having more runway is great for safety, planning to use less of the runway is not a huge benefit: you always plan to have enough runway left if you need to abort during the take-off roll. It's much better to have more height quickly in the climb-out: it gives you more margin against obstacles after the runway's protected area, and it gives you more height to land in case of an engine failure after take-off (EFATO).

The numbers for a normal take-off optimise for a good rate of climb, which has the greatest benefit to safety. A short-field take-off gives you an extra option when the runway length is too short for that - at the cost of some margin if there's a problem in the climb-out.


Can a person with Type 1 Diabetes get a medical and learn to fly?

As far as the FAA is concerned your friend can get a medical, but he will need a special issuance medical, will only qualify for a third-class medical, and will be prohibited from operating aircraft outside the United States.
In addition there are some specific requirements to obtain the special-issuance medical for insulin-dependent diabetics, and monitoring requirements before and during flight which must be adhered to.

The FAA has a page of guidance for Aviation Medical Examiners that deals with insulin-dependent diabetes which your friend should review (and be prepared to discuss with their AME).
Diabetes.org also has a page on Diabetes and FAA Certification, and AOPA's medical folks would be a useful resource to help ensure that the special issuance medical goes through without any hiccups.


What would the ranks most likely be of the crew of a B-1B?

In general, the pilot could be a captain, major, or lt col, the copilot probably a 1lt or captain, and the navs any of the above. For a select crew handpicked for a "fate of the world" mission, you might put 2 instructor pilots together along with two senior navs, so all 4 as lt cols wouldn't be impossible. On the other hand, if the crew is essentially detailed off to be "secret squirrels" for a while, it probably wouldn't be stacked quite that high, so maybe a mix of majors & captains. That happens because it quickly becomes disruptive to take senior guys (tactics officers, instructors, the ops officer or commander, etc) away from their regular squadron jobs for a prolonged period. The more important the mission, the more that disruption is accepted.


How much rudder input does a Cessna 172 require during the take off roll?

With several hundred hours logged on multiple variants of the 172, I would give the relative answer of ‘not much’.  In my experience a C-172 tracks pretty straight with only slight right rudder pressure needed on the ground roll.  It is much less than what is required for a C-182, 206, 210 or other high performance single engine Cessnas and much less that a lot of tailwheel airplanes I’ve flown.

It seems like in a 172 when you are brakes off and rolling, I usually rest my heels on the cockpit floor and apply a slight pressure on the base of the right rudder pedal with the ball of my right foot.  It is necessary as the plane will waltz to the left during the takeoff roll if you don’t.  But the force applied and the deflection of the right rudder pedal is light and limited, if you do it right.

A recommendation might be to send a developer down to a local flight school operating the C-172 and arrange to practice takeoffs and landings with a CFI so they can get an empirical sense for what rudder input is needed on a takeoff roll.


You could try to get some cheap Car GPS trackers on aliExpress. But they would need to be in range of cell towers. Flying to high will cause connection loss.

A more expensive one, which I found to be working great is this one.

But you can get android based trackers for about 10\$US.


Why does the U.S. keep thousands of retired aircraft in storage?

Some aircraft sold or loaned to outside military forces are built in batches. These aircraft stay in service for a longer period of time than those in the advancing military power, making spares very difficult to obtain and replacement aircraft for those lost in action are going to be impossable to get. I remember on 19 Squadron in RAFG Wildenrath (1979/82), the F4 Phantom was very demanding on which panels and parts would swop between aircraft. The Phantom also went through many states of evolution and when our Govenment decided it was cheaper to buy more F4 aircraft, they had to consider the spares, fitment and training that would be needed to keep our units similar. The Phantoms that were purchased I believe came from the boneyard.
Of course, the 'all out war' theroy also holds true, if a planet size war was to break out, and you recall all your old pilots.... easier to shove them in aircraft they flew 30-40 years ago than train them in the newer stuff.... going to get very messy up there and replacing pilots/ planes will be a priority, numbers can sometimes win wars. Life expectancy of our frontline pilots were 2/3 sorties at best, Ground crew in fixed bases were 2 days at most..... I miss the old days.


What runway materials reduce skidding in wet conditions?

This question has kept industry awake at night for ages now. A good start is here.

TL; DR: In addition to grooving, some runways (e.g. London City) apply a special surface material that is called a Porous Friction Course.

  An alternative to grooving as a means of facilitating surface water dispersal is the laying of a Porous Friction Course (PFC) which allows water to pass vertically through the surface layer and then move horizontally clear of the runway beneath, but essentially parallel to the surface.

The trouble with all that is that if you test it, build it and then calculate performance taking credit for it, if it doesn’t work for real for whatever unknown unknown, you are likely to find out by having to remove an aircraft from the Thames river which is kind of frowned upon by most. You want to be a bit conservative with runway friction.


What is the direction convention for Roll angle?

That depends on the coordinate system, and the Wikipedia answer uses the most common convention. Flight mechanics uses a coordinate system with X in flight direction, Y sideways to the right and Z downwards positive. If you now apply the right-hand-rule for the positive direction of rotation around each axis, you will get a positive roll angle around X when the right wing moves down.

Right-hand-rule for rotation: Point the thumb in positive axis direction, then the other fingers will point into the positive direction of rotation.

If, however, X points backwards, then a positive roll angle would be as used in the linked library. Such a coordinate system is sometimes used to have Z point up, but is rather unusual for flight mechanics.


What do different runway depictions mean in the Chart Supplement?

The glossary I'm looking at (page 13 from the current South Central US Chart Supplement) says that that style of dashed line indicates Runway Centerline Lighting.  So runways that have the dashed lines have lights on the runway.

The complete chart supplements are available online from the FAA, and the glossary for each one is easily found about Page 13 for each section.


Is there any electrical component on an aircraft which can never be turned off by a pilot?

One example of a system that cannot be switched off by the pilot that is probably more common to all other airframes than just the one airframe I'm indicating.

Whenever electrical power is applied to a Gulfstream G550, whether it is powered by battery, generators, an apu, or some external power source, each engine's FADEC Electronic Engine Control (EEC) computer will be powered and the pilot can not switch them off.

The pilot could only indirectly turns them off by switching off all power sources.

However, when the engines are running, he can't even do that since there is an engine-driven generator dedicated to powering the EECs in the event of a total power loss.

In fact, while the engine is running or even windmilling above 35% rpm, the EEC's dedicated generator is supplying all power to the EEC and there is no switch or circuit protection that can be manipulated by the pilot to interrupt it.


When may passengers board the aircraft and who makes the decision?

It is a joint decision of the entire flight crew (flight crew consists of pilots and cabin crew).

It is mostly a decision by the most senior flight attendant because it is mostly a cabin issue. The prerequisite is, obviously, the cabin has to be cleaned and prepared. There are "cabin checks" to be carried out when the plane is empty. Typically, each flight attendant will be assigned an area. When everyone reports they're ready, then boarding can begin.

But there are factors from the cockpit that can delay the boarding process too. For example, ATC informs them that takeoff will be delayed for 2 hours. Or a maintenance is being carried out. So, the pilots would always been informed before boarding begins, but in most cases there'd be no objection.


Could a commercial plane like Airbus A320 glide with no working engines from 11000 meters?

All standard fixed wing aircraft are able to glide. The key measure of performance in gliding is the glide ratio which is related to the lift-to-drag ratio of the aircraft. The glide ratio of a clean A320 is 17:1 which means it can travel 17 units of distance forwards for every 1 unit of distance downward at best glide speed. Using your figure of 11,000 meters away and multiplying by 17 results in a maximum range of 187km . In practice, the aircraft would need to be higher than this (or land closer) to accomodate turns and other factors, but if the A320 was at 1000 meters AGL or higher I would expect it to have no problem landing at an airfield or airport 11km away. Note that aircraft routinely glide every time you fly even though you may be unaware of it. When a commercial flight begins its descent often power will be brought back to idle, so the aircraft is gliding at that point.

There have been several instances of large commercial aircraft landing fully unpowered. One well known example is the case of the "Gimli" glider in which a Boeing 767 ran out of fuel and glided to landing at a nearby airbase.

EDIT: It has been brought to my attention that the OP is asking about a starting altitude, not how far away from the airfield. As I imply in my answer what matters is the ratio of altitude and distance, not altitude alone.


What does the letter G mean in a runway identifier?

For runways with other than hard surfaces it is common to list the runways with a letter G for grass or in the case of a seaplane base, with W for water.

An example of this is runway 8G at Boulder (KBDU) and runway 35W at David Wayne Hooks (KDWH).

You can see this information in the Chart Supplement pages and diagrams for each airport.


Helicopters: why hasn't NOTAR been more popular?

Though NOTAR looks simple from outside, its actually a bit complicated. Let me use the following figure to elaborate on this point.

By Voytek S - Own workThis vector image was created with Inkscape., CC BY-SA 3.0, Link

Details from the figure: 1. Air intake
    2. Variable pitch fan
    3. Tail boom with Coanda Slots
    4. Vertical stabilizers
    5. Direct jet thruster
    6. Downwash
    7. Circulation control tailboom cross-section
    8. Anti-torque lift

You have the ducted fan (2), which is driven using power from the gearbox, which is used to produce the anti-torque effect through Coandă effect. Note that this fan has a variable pitch, which is adjusted similar to the tail rotor.

The Coandă effect actually provides only about two thirds of the required anti torque. The other one third is provided by the directed jet thruster (5) which rotates about the tail boom axis (that is why it is projecting outside) like a rotating can.

The problem is that in cruise, the effect is markedly reduced by the airflow over the tail boom, which is overcome by making the vertical stabilizers (4) adjustable. So basically, you have three systems for adjusting the anti-torque, compared to one in the conventional tail rotor. More systems translates into more parts, more complexity, more chances of failure and more maintenance, not to mention that this makes the helicopter tail heavy. For example, when using the same engine, the NOTAR MD 520N is heavier than the conventional MD 500E (from which it was developed) (Source:1, 2).

As you've noted, this system is not as fuel efficient and sacrifices speed and range for lesser noise and improved safety. Its a tradeoff and most operator would take the better performance over others.

In case of military helicopters, the main problem for helicopters, the infra-red detection, is improved in case of NOTAR only if the engine exhaust (or part of it) is routed through the fan, as the South Africans did with the Aérospatiale Alouette III III in their Cirstel (Combined Infra Red Suppression and Tail rotor Elimination) project.

Denel Cristel; image from stingrayslistofrotorcraft

As the site explains,

  The Cirstel principle splits the high pressure air from the engine for use in the Coanda slots, while the low pressure air is bled-off for the tail thruster and to mix and cool the engine exhaust. The thruster nozzle is a Denel-patented clamshell design, unlike McDonnell Douglas' `rotating can' concept.

As you can see, the system is further complicated. In addition, routing the hot air through the tail boom brings its own headaches and is better avoided. So, even in that sense, the advantage is not striking.


How does one interpret the satellite data on flight MH370?

TL;DR.

Use the BTO not the difference in time-stamps for request & acknowledge.
BTO is an offset in μs, not a round-trip time.
There's a mean bias value (-495,679 μs) that includes the signal processing delays in equipment.
The distance is ground-station to satellite to aircraft to satellite to ground-station.

Inmarsat data

As I understand it, to calculate distance you should be starting with the Burst Timing Offset (BTO) not the difference between time-stamps in the Inmarsat data. There are latencies in various stages in the electronic processing of messages, not all of these are distance related.

Time    BTO(μS)
19:41   11500
20:41   11740
21:41   12780
22:41   14540
00:10   18040

There's an example on page 54 of MH370 - Definition of Underwater Search Areas:

The aircraft AND the satellite are in motion in three dimensions

The satellite is at an altitude of around 35,811 km above the earth's surface, the satellite is moving cyclically north and south of the equator and the aircraft is flying over a roughly oblate spheroid so changes in it's distance from the satellite are not a simple function of changes in the aircraft position relative to the surface.

Not to scale. E&OE. etc

References

Inmarsat 3-F1 satellite position
Inmarsat 3-F1 satellite tracking
Inmarsat raw log data for MH370
MH370 - Definition of Underwater Search Areas


Why do most commercial solid-state Inertial Measurement Units (IMUs) measure angular rate and not angular acceleration?

My answer assumes that you're asking about having IMUs measure angular acceleration instead of angular rate; if meant they should measure angular acceleration in addition to angular rate, then I apologize for misunderstanding you.

  However, having available the angular acceleration would be useful for a more precise kinematic model when integrating to find the pose.

I'm not sure where you're getting that information. When integrating to find the attitude, the angular rate is much more useful than the angular acceleration.

An attitude indicator essentially just takes the angular rate and integrates it. However, there are two sources of error here: errors from the sensor, and the fact that the direction of gravity changes as the earth rotates and as you move across the surface. But both of these errors can be corrected by mixing proper acceleration into the calculation.

On the other hand, if you only had access to angular acceleration data, you'd need to integrate twice to find the attitude: once to come up with an estimate of the angular rate and again to come up with an estimate of the attitude. (Why would you want to have to integrate to come up with an estimate of the angular rate, instead of just measuring the angular rate?)

This would introduce a third source of error into the attitude indicator: errors that result from accumulated errors in the angular rate estimate. I think these errors would be much more difficult to correct.

I think that the biggest problem is that in a coordinated turn, the angular acceleration is 0 and the lateral proper acceleration is also 0, so without measuring angular rate, an IMU would be unable to distinguish a coordinated turn from straight-and-level flight! That's a critical flaw.

In short, you need a reliable measurement of angular rate, and that can't be obtained from a measurement of angular acceleration.


What is the procedure when a required A/D inspection via an AMOC has gone overdue?

Each AD is specific (and unique) to the procedures and compliance outlined in the AD. If the AD does not say otherwise, all that is needed is to comply with it (do the inspection), and then make an entry in the maintenance log book, and you will be good to go.

I have never seen an AD that addresses circumstances when not previously complied with. For example, a Cessna 172 requires an inspection of the horizontal stabilizer spar; it does not matter if no one has done it for 45yrs. All that is needed is to do the required inspection and it is good to go :)


How is fuel vapor dealt with at large airports?

Large airplanes are pressure refuelled so vapor escaping through the fuel port is not an issue as it is in smaller airplanes.  You are correct, however, that the fuel/air mixture existing in the tank will be displaced by the incoming fuel.  The wings will have vents installed that will allow the air mixture in the tank to escape (and fuel in the case of over fuelling or excess expansion of the fuel after it is loaded).

The fire risk is minimized in three ways I can think of:

The airplane is grounded to the fuel truck, minimizing the risk of ignition via sparking.
The wing vents have flame arrestors so that if the air mixture leaving the wing did ignite, the flame would not make it into the tank.
Atmospheric dispersion -- once the air mixture is out of the tank it will become more dilute with time.

In the cases there is more than vapor released, e.g. liquid fuel is expelled, these spills will be absorbed to minimize fire risk.  In the ultimate case of fire the fuel truck has fire extinguishers and there is a fire station on the airport that can apply foam and water as needed.


Why do aircraft need a vertical tailfin, but birds don't? (and lots of fish do?)

Not all of them need a fin:

This is the Horten IV, a flying wing glider that did not need a fin (picture source). Instead, it used spoilers at the wingtips to create yawing moments, and the swept wing helped in improving its weak directional stability. It could afford to do so because it was a glider. The second prototype of a jet-powered flying wing, the Horten IX V2, suffered a crash when one engine failed and the pilot could not end the resulting spiral dive.

Fins on airplanes

Birds have two advantages over airplanes which make a fin superfluous:

A variable geometry wing, where wing span, sweep and incidence can be controlled for each side independently.
Propulsion is integrated into the wing, instead of separate power plants which might fail independently.

An extra advantage of birds over older airplane designs lacking a computerized control system is that the bird's brain is wired to adjust the wing on each side subconsciously and continuously. While a fin provides an aircraft with weathervane stability, a bird is inherently indifferent (neither stable nor unstable) and needs continuous tweaking of its wings for directional control.

If a bird wants to control yaw, it simply adjusts its wingtips such that the drag difference between both creates the desired moment. It can do this by reducing wingspan on one side, which also creates a rolling moment for a coordinated turn. Airplanes unfortunately cannot do the same.

Airplanes need positive directional stability because humans cannot adjust the controls continuously - they need to check maps or work the radio, or maybe just want to relax for a moment. Also, multi-engined designs need a stability margin to compensate the asymmetric thrust resulting from a failed engine. With a fin, the mass of the structure behind the center of gravity now needs a compensating mass ahead of it, and the side area of this forward fuselage is de-stabilizing the aircraft in yaw, requiring yet more area at the vertical tail. This is another problem that birds do not face.

The B-52H 61-023 suffered a structural failure of the fin on January 10, 1964, but managed to limp home with almost no lateral stability left. Had it suffered an additional engine failure, it would had crashed (picture source).

Fins on fish

The dorsal fin of fish helps in their propulsion by balancing the areas above and below their vertebral column. By wagging the tail, they create a side force which creates a sideslip condition at the dorsal fin, which in turn produces a correcting side force so the body does not roll while swimming. In this it can be compared to the keel of a sailboat. The hydrodynamic forces on a keel counteract the side force from the sail in crosswind conditions. Its main function is to stabilize the fish from the yawing motion caused by their tail fins, and this stabilization in turn improves the efficiency of the motion of the tail fin.

An additional function is as a roll sensor. Being located at the maximum girth, it gives the best readings of local sideways motion due to roll. This is the main function in marine mammals where the tail fins are horizontally oriented. In fish which have an adipose fin (located aft of the main fin), this fin is most likely their roll sensor.

It is not used for roll control (except as a sensor in a feedback loop), and cannot because it is not adjustable. Roll control is achieved by the adjustable pelvic fins. It also cannot provide roll stability - this would require it to roll the fish back to its initial attitude after a disturbance. All it can do for the roll movement is to dampen it a little and prevent it when the fin is moved sideways.


Which 'pusher' propeller aircraft have been used in active military service?

If you also count drones, the General Atomics MQ-9 Reaper Drone is a pusher propeller aircraft in active service.

Here are some others:

Convair B-36 Peacemaker
Vickers F.B.5 "Gun Bus"
Airco DH.2
Curtis Model E
Royal Aircraft Factory F.E.2
Royal Aircraft Factory F.E.8
Voisin III Bomber
Boeing GA-1

You may notice that a lot of these aircraft are very old designs. The problem is in 1914 the US Army (there was no US Air Force yet) banned pusher type aircraft after a number of pilots died in them. This mentality carried over on the other side "of the pond" and very few pusher type aircraft entered service after 1916. The SAAB 21 was responsible for the development of ejection seats because a major problem with bailing out was hitting the propeller. Because the prop was behind the pilot, bailing out meant getting pushed through the wood chipper...

The B-36 is a good example of this configuration in its limits. It is a massive aircraft with a 19 foot propeller (second largest propellers in use). Engine fires were common due to mounting the engines backwards and not getting sufficient heat over the carburetors. The aircraft was later modified as the XB-60 with swept wings and 8 jet engines but was inferior to the Boeing XB-52 (later becoming the B-52) and was abandoned.

The other problem is that a pusher type design contributes a lot to the drag of the aircraft and is relatively inefficient compared to tractor designs. By the time swept wings were in fashion (mostly because jet engines pushed speeds higher and higher),  the need for propeller driven military aircraft dropped dramatically in the jet age.


How does a fighter jet perform good and quick maneuvers with such small wings?

Fighter (combat) aircraft are designed to perform quick maneuvers in order to get into a position quickly to engage and shoot down an enemy aircraft or evade incoming threats (like missiles, etc.). Civil aircraft like airliners are designed with other things in mind like comfort, safety, reduced fuel consumption, etc.

The wings are only a part of the story in performing maneuvers like those performed in air combat maneuvering, which depends on a number of aircraft characteristics like,

Power - For carrying out most of the maneuvers (like wingover), the excess power available matters. Fighter aircraft have more excess power, which translates into more acceleration. That allows it it enter into maneuvers quickly compared to the civil aircraft. In case of emergencies, the combat aircraft can use their afterburners to gain significant extra power.
Thrust-to-Weight Ratio - Most of the modern fighters have high thrust-to-weight ratios, usually more than 1 (which allows them to accelerate in vertical climb). This allows the fighters to accelerate far faster compared to the civil aircraft. For example, F-15 (>1) had a thrust-to-weight ratio more the three times that of the Concorde (~0.33).

Source: strategypage.com

Stability Most of the fighter aircraft today are designed to be unstable. This makes the aircraft respond to control inputs much more quickly compared to the airliners (which are usually not unstable in the roll axis). This means that the combat aircraft are capable of maneuvering much more quickly.
Inertia In case of large wings, the roll inertia is very high. This prevents them from performing quick maneuvers. Also, the damping of the large wings is also to be considered. In case of fighters, however, the short wings, having smaller inertia helps in achieving high roll rates.
Wing Loading The smaller the wing loading, the better the turn performance. Most of the combat aircraft employ a blended wing-fuselage design, that reduces the load on the wings. For example, the Eurofighter Typhoon (~300 kg/$m^{2}$) has about half the wing loading of A380 (>600 kg/$m^{2}$). In fact, an F-15 produced enough lift with half a wing gone to perform a successful landing.

Source:www.armchairgeneral.com

Control Surfaces- In general, the combat aircraft have more number of control surfaces like canards (in addition to primary control surfaces) compared to the civil aircraft. This enables the pilot to maneuver the aircraft much more quickly compared to airliners.

Source: www.blokeish.com

Due to these reasons, the fighter aircraft are able to perform maneuvers much better and faster compared to airliners.


How are timed flybys executed, and what are their accuracy?

The way they coordinate them is actually extremely simple.  The show at a ball game (or any major event) is usually very heavily choreographed, so they know exactly when it's going to end (seriously, often down to the exact second.  They practice the heck out of those things.)  So, step number one, the organizers tell the Military the exact time for the flyover in the show.

For the militaries part, well, it's important to remember that military aviation involves a lot of instances where you have to be over a target, dropping a munition, at an extremely precise time (again, down to the second).  Otherwise you may screw up the timing of the whole operation, or the target may be gone, or the defenses may be up (etc etc).  It's really important to be precise in the military.

The procedure itself is still fairly conventional though.  You figure out what time you need to be there, then you figure out how much time it will take you to get there.  Subtract the latter from the former and boom, you have the time you need to take off.  Then all they need is a few check points to make sure they are on schedule, approaching at the proper speed.  And they adjust as needs be.

Basically, keep an eye on the clock, slow down if you're ahead of schedule, speed up if you're behind.  To increase accuracy, you may build in a holding spot near the event, that way if you're 20 minutes early (of if the planning goes out the window for the show and they're late...), you can hold there and pick the approach up again when the time is right.  It's still all about watching the speed and the clock though.  With a lot of practice, you end up hitting your waypoints, hold points and destination, with (literal) military precision.

If you want to know more details though, check out this article from ESPN: How Flyovers Hit Their Exact Marks at Games.

As a final thought, I think you may need to adjust your thought experiment.  Military aircraft can get clearance through just about any airspace prior to the actual mission.  Plus, they can approach from any direction, so it's pretty easy to find a lane that has no traffic.  So in your car thought experiment, there should have been no traffic and a straight shot to the overpass.

Plus, there should have been regular beacons (like GPS or NDB fixes) to tell you how far you are from that overpass.  And the person driving the car would have known exactly what time they needed to pass each beacon in order to get to the overpass in time.  Then, with a heck of a lot of practice, I'm sure that driver could go under that underpass at the exact right moment pretty much every single time...


What is automatic control connections and how does it work?

The automatic hookup uses a catchment area to mechanically force the pushrod into a receptacle to ensure a proper mechanical connection when the parts of the plane are connected.

As an example, I have sketched below how the ailerons would be connected. The blue structure is the fuselage-side part, and the green structure is the wing-side part of the control linkage. The pushrod coming from the stick is connected to a trapezoidal cone which is hinged at the same point as the wing-mounted pivot lever which is moving the pushrod connected to the aileron.

The opening of the trapezoidal cone is sized such that the end of the pivot lever will always be caught by it, regardless of the stick position and the aileron deflection. At the base where the end of the pivot lever rests when both parts are connected, the exact position and play between both can be adjusted, so the automatic connection will not have an adverse effect on handling.

I once witnessed an aborted winch launch of the SB-8 in which the linkages to the ailerons were interchanged. The pilot noticed the wrong operation of his ailerons before becoming airborne and released the rope quickly, but could not avoid a ground-loop, because he had pushed the low wing into the ground when trying to correct the plane's attitude. I was glad not to have been in his position, because I am not sure I had reacted as quickly. Automatic connections would have made this mishap impossible.


Is there any free source for current airline schedule data?

I am currently developing a plugin for virtual airlines to pull live data, and I use the FlightAware's API which is really good in my opinion. With a little bit of php magic you can get all the schedules for your airlines for free (if you sign up for the free account) or you can pay to get access to the getAirlineSchedule query which just basically does what it says.

https://uk.flightaware.com/commercial/flightxml/

There is the website if you're interested, to get access to the free area, sign up and click the 'get prices' area and the very left option should be the free pack ;)
If you're interested in my code which I am developing, you can check it out at my github;

https://github.com/RAZERZ/PullFlightData

Good luck ;)

EDIT: You get the data in the form of json, so you can pull strings of data from there :)


What procedures do I have to follow to fly a seaplane from the US to Canada?

Whenever you land in the US from a departure point not in the US, you have to land at an Airport of Entry as your first US destination airport. It does not have to be a big airport. There are plenty of Class D airports that qualify. You can verify which airports are AOEs in the US Chart Supplement. Some (big ones) are also marked as such on the sectionals.
When crossing the US border, you will need to have arranged customs clearance with the US CBP beforehand if you are landing at a small AOE. You may also need a US CBP DTOPS decal for your aircraft. Then, of course, there is the flight plan. Once you have cleared US CBP, you can fly to any other US domestic destination of your choice.
I would think that when flying into Canada, the TCCA would have similar rules.


How much is the fuel consumption of a Tecnam P2002?

Make your search based on the engine model, Rotax 912S2, not the aircraft.

However you can work it out easily for any aircraft and engine if you remember that carbureted gasoline engines burn about .4 to .45 lbs/hp/hr. The rotax is pretty efficient so you can use .4 (old air cooled direct drive carbureted engines like Lycomings are closer to .45).  So at 75hp in cruise, that's 30 lb/hr at cruise or 4.4 US gal/hr or about 17l/hr.


How long after the last departure shall the airport stay open for an emergency return?

Where I work, we have to stay in the tower for 15 minutes after the last departure in case they need to return. To my knowledge, there are no international regulations about this, so the rules may well be different from place to place.


How do airline pilots contact their company while in the air?

While enroute the primary communication with company is via ACARS. (Aircraft Communications Addressing and Reporting System)

This is a digital datalink system and is kind of like sending text messages. On modern aircraft like a B777 it operates on HF, VHF, or SATCOM so there is coverage almost anywhere in the world.

If the aircraft is close to an airport with a company frequency, regular VHF radio communication can also be used.  Some airlines may even have company Peripheral stations (PAL) at certain locations so they can use a VHF radio to talk directly to Dispatch from hundreds of miles away.

In the USA, VHF company frequencies are allocated by Aviation Spectrum Resources, Inc. (ASRI) ASRI Ground Station Administration Service (AGSA)

SATCOM is also be used to make Satellite phone calls so we can talk directly to Dispatch or Maintenance from thousands of miles away. You can use pre-selected company numbers or manually enter any phone number.

Aircraft without SATCOM can use VHF or HF radios to contact ARINC (Aeronautical Radio, Incorporated) who can create a phone patch to any phone number.  Aeronautical Radio, Incorporated (ARINC)

Source: B777 Aircraft Operating Manual Volume 2 (2.23 Communications)


Do airliners like Boeing and Airbus use airfoil variation along the span for their wings?

Every good design varies at least the thickness: While the root needs to be thicker to enclose an efficient spar, the tip can be optimised for aerodynamics, which usually results in a root thickness of 16% to 21% and a tip thickness between 9% and 13%. Look at Dave Lednicer's incomplete guide to airfoil usage for an exhaustive collection of aircraft and their respective root and tip airfoils. Generally, larger aircraft tend to use thicker airfoils because scaling laws dictate that their structure has to carry higher loads.

Transsonic designs like airliners need to pay special attention to thickness because a thicker airfoil will encounter local supersonic flow at lower flight Mach numbers. Also, a thicker wing will store more fuel and will be lighter, so the compromise is around 13% thickness on average. With supercritical airfoils, a root thickness of 15% and a tip thickness of 11% has become widely used. Unfortunately, the exact airfoils of modern airliners are not published.

Another reason for varying airfoils is wing sweep. Left with the same airfoil over span, the isobars on the surface would show less sweep, creating a steep pressure recovery at the center wing (with potential for early stall) and suction peaks near the leading edge at the tips. Such an isobar pattern will use the available wing area less efficiently, so designers strive to make the isobars parallel to the local sweep angle by adjusting the local airfoils. At the root the maximum thickness must be shifted forward while tip airfoils need a more backward maximum thickness. Also, camber near the root is reduced up to the point where negative camber along the mid section of the airfoil chord is used.

Here are a few older ones:

Type                        Root airfoil           Tip airfoil
Boeing 377 Stratocruiser    Boeing 117 (22%)       Boeing 117 (9%)
Douglas DC-7                NACA 23016 (16%)       NACA 23012 (12%)
Lockheed 749 Constellation  NACA 23018 (18%)       NACA 4412 (12%)
Lockheed 385 L-1011 TriStar  ? 12.4%                ? 9%
Saab 340                    NASA MS(1)-0316 (16%)  NASA MS(1)-0312 (12%)
Tupolev Tu-104              PR-1-10S-9 (15.7%)     PR-1-10S-9 (12%)
Vickers VC-10               Pearcey 13%            Pearcey 9.75%
VFW 614                     NACA 63A015 (15%)      NACA 65A012 (12%)

Modern CFD techniques and composite structures allow to optimise the local contour at the wing-fuselage intersection such that no single root airfoil is used but a continuous variation which delays local flow separation and shock strength as much as possible. This also means that no stock airfoil is used, and most modern designs have their custom-made airfoils.


How to define the aileron's deflection angle (in the Laplace domain)?

It looks like a transfer function for a feedback loop, which is a function of time and transformed into the frequency domain. Input is the aileron deflection $\delta(s)$, output is the roll angle $\phi(s)$. When deflecting the ailerons, the aircraft is accelerated around the X-axis. The roll movement creates a damping force proportional to span $b$, which quickly dampens out the roll acceleration into a steady roll rate.

So achieving a roll angle depends on the moment of inertia around the X-axis, and wing area geometrical data, plus the time that the aileron is deflected at a certain angle. In order to get to a specific bank angle, the aileron needs to be deflected, then returned to zero before the bank angle is achieved - damping and inertia will then continue to roll the aircraft until the target bank angle is achieved.

The transfer functions defined in the frequency domain are used for determining gain and phase shift, more info for instance here, section 6.3 onwards. Using a signal in the frequency domain gets to be a pain once the deflection is a real world time history and not a mathematical function like a sine wave or a pure step input.

Image source

Once the gains are determined with the Bode plots, the block diagram of the transfer function is pretty useful for determining bank angle as a function of the time history of aileron deflection: just read the actual bank angle, subtract from the desired bank angle, and set the aileron deflection angle in real time according to the difference signal.

EDIT

Have managed to have a look into the book. I'm familiar with the equations, describing stability and control of aircraft. Your question on how to define an input signal in the frequency domain is a pertinent one: it would have to be defined mathematically in the frequency domain as well. I have only seen use of the frequency domain equations in off-line analysis, not in real-time use since the inputs are never purely mathematically defined. Equations such as 5.53 for the time domain. Then any input signal can be added in real time, multiplied with the gains found from the Laplace transform, integrated and output.

  So my first question is: suppose you want to imply the aileron rotated 45degrees how does that translate to δ(s)?

It depends how fast you bring the ailerons to 45º, for how long you keep them there, and what happens next. If it is a step response, the function is $\frac{0.785}{S}$. The aircraft will respond with a steady roll rate (in aeroplane axes) and will never establish a constant bank angle.


What were the typical dimensions of a WW2 US bomber formation?

The size of the bomber formations (bombers streams) varied significantly depending on the number of bombers , the time , location and other things. The most common figure quoted figure is around 70 miles long and  5-6 miles wide (for ~500-600 bombers). However, the formation's footprint depended on a number of factors ranging from the navigator's skill to the wind in that area.

The figures vary wildly. For example, from the book Mission to Berlin: The American Airmen Who Struck the Heart of Hitler's Reich:

  The stream of more than one thousand Eighth Air Force bombers, from one end to another was 360 miles long. ... on ... February 3, 1945, when the first flying fortresses reached Berlin, the last bomber was over the Zuiderzee in Holland.

This extreme length is a consequence of the situation late in the war, where allied air armada roamed European skies without bothering much about the Luftwaffe. The time spent over the target, on the other hand was quite small-

  ... each Fortress crew would spend only between thirty and sixty seconds over the center of Berlin itself...

Note that there was no such thing as precision bombing in WWII (except for some special cases), though the accuracy did improve over the war. Of course, some of this was due to the way the 'target' was designated- anywhere 1000' of the aiming point was good enough. From The United States Strategic Bombing Survey:

  Conventionally the air forces designated as "the target area" a circle having a radius of 1000 feet around the aiming point of attack. While accuracy improved during the war, Survey studies show that, in the over-all, only about 20% of the bombs aimed at precision targets fell within this target area. A peak accuracy of 70% was reached for the month of February 1945.

Accuracy of RAF night bombing improved from ~20% in 1942 to > 90% in 1945. Of course, the British target was comparatively larger- anything within a 3 miles radius of the aiming point was a 'hit'.


How do I calculate the lift force on an aileron?

Cessna Cardinal planform, I don't know how to put this in a comment


What runway has the steepest climb requirement on take-off?

The first one that came to mind is London City Airport (EGLC) which is world famous for its steep approaches, and for which I found these requirements on its departure charts:

  OBSTACLE CLEARANCE -
  RWY 09: Maintain minimum 6.76% climb gradient to 275 (258).
  RWY 27: Maintain minimum 7.20% climb gradient to 1102 (1085).

(Where the first number is altitude in feet and the second number is AAL, above aerodrome level)


What does mean "fl oz"?

"fl oz" means fluid ounce (1 fl oz ≈ 30 ml), which is a unit of volume, as opposed to dry ounce, which is a unit of mass.

How are they calculated the 30:1 ratio?

By ratioing 128:4.26, it is 30.05:1, so 30:1 is a good approximation

What does mean "2-cycle oil"?

It is oil for 2-cycle/stroke piston engines

from where these numbers have came?

Probably some design specs/limitations. You have to ask them if you want the details.

What does it mean?

That when you refuel, for every 30 parts of fuel you put in the tank, you need 1 part of oil for correct lubrication of the engine.


What climb rates can the Airbus A320-200 achieve and which climb rates are commonly used for normal flight operations?

There's a lot of nonsense being banded about regarding this flight.
First up, we are not talking about sustained, powered climb rates. If you're travelling at Mach 0.85 and pull up vertically, in theory (if your plane didn't break) you'd climb at an initial rate of nearly Mach 0.85 (your original speed minus the airspeed loss when pulling up).... That's near enough 57,000 feet/minute.
If you're at high speed and willing to trade speed for altitude, an Airbus A320 is physically capable of climbing at much higher rates than 6000 feet per minute.... At least until it runs out of airspeed.
A fighter is the only aircraft which would be likely to perform a sustained 6000ft/minute climb rate in normal use, but they're also capable of much higher rates of climb.
The maximum rate of climb you'd see in an A320 in normal use is in the 2000 ft/min range, but that's because it's the highest reasonably efficient rate of climb. That's not the maximum the aircraft is capable of under power (which is more in the region of 4000 ft/min), and is absolutely no indication of that maximum unsustained climb rate.
It would eventually stall at any unsustainable rate of climb, but then again, so would any aircraft even at a sustainable rate... Keep climbing and before too long you run out of atmosphere.
Either way, there is nothing to say that climbing above the sustained climb rate for an aircraft is unsafe or, necessarily, unusual. You trade airspeed for altitude, sure, but if you need to be higher at that moment in time, there's plenty of time to accelerate again later.
From Airlines.Net:

The three are roughly the same at 10,000', at about 2500 fpm. (Maybe a bit more for a light A319, and less for a full A321)
Normal climb rates from 10,000' to about 30,000 are as follows:
A319, 3000 fpm to about 1500 at 30,000'
A320, 2200 fpm to about 1000 at 30,000'
A321, 1400 fpm to about 500 at 30,000'

TL;DR - The official is spouting nonsense s/he doesn't understand. A fighter is the only aircraft likely to be able to (or wish to) climb at a 6000 ft/minute SUSTAINED climb rate, but almost any aircraft can climb at that rate for brief durations in a zoom climb - converting airspeed/momentum to altitude


Which book should I study to learning flying in Australia?

CASA (the Civil Aviation Safety Authority) has a number of resources that might be of interest, in fact a lot of their safety publications and videos are as good as (or better than) the FAA equivalents. As best I can tell they don't have anything equivalent to the textbook-level Airplane Flying Handbook or Instrument Procedures Handbook from the FAA though.

You can find references to the FAA handbooks in some of CASA's CAAPs - for example, the Night VFR Rating information references the Airplane Flying Handbook's section on Night Operations) - so clearly they consider at least some of the information broadly transferrable.

Like Farhan mentioned the operating principles, maneuvers, etc. are going to be largely the same because the plane doesn't care what country it's in. It's the specific regulations (and regulatory citations), airspace design specifics, etc. that will vary but if you're aware of that you can easily pick out the parts that you should pay attention to versus the parts you'll need to go and cross-check in an appropriate Australian reference like the Part 61 Manual of Standards for flight training / practical test requirements.


How can I keep my IR currency outside the USA?

The easiest option is to find a US CFI/AI holder in the country you are in, to sign off on your approaches.  It might be allot easier if s/he is also a Spanish CFI particularly if you are flying in a Spanish registered aircraft.  You do not indicate if you hold a certificate from Spain.

It is not uncommon to find instructors with US FAA CFI ratings in other countries.

There is no prohibition of a US CFI giving instruction in another country.  There may be of a given country, or operational limitations imposed by aircraft registration, host country operating rules, and insurance limitations, as well as owner / lease limitations.

However, I routinely sign off US pilots for approaches made at Canadian airports, in fulfillment of their US instrument recency requirements.


What is the purpose of proximity sensors on hydraulic systems?

A proximity sensor is any sensor that detects whether there is something in its proximity (within specified distance).

There are many kinds of proximity sensors (optical, magnetic, capacitive etc.) that detect different kinds of target objects and to various distances.

In this case, proximity sensor is used to detect position of the spoiler. Proximity sensors are preferred over micro-switches because they are more reliable, since they have no moving parts and thus don't wear out.

For parts actuated with hydraulics they are the only way to detect the position, since hydraulic actuators don't provide any direct way for detecting their position (compared to electric actuators, where in some cases the response of the actuator can be used to detect the position; the principle is similar to a magnetic proximity sensor anyway though).


What does “to the numbers” mean in landing clearance?

Typically it's phrased as "direct to the numbers" and means you should proceed in a straight line from your present position to where the runway numbers are painted on the pavement. This instruction can be issued to fixed-wing aircraft as well, but perhaps not from as wide a range of starting positions. It relieves you of any previous restrictions.


How do aircraft refueling in-air deal with wake turbulence?

Ex US Navy pilot here.  I flew the S-3 Viking, which refueled via the probe/drogue method, as opposed to the USAF flying boom method.  I can confirm that the receiving plane is below the wake turbulence of the tanker, maybe by 8–10 feet.  Although, even if you should ride up into the wake, the sensation is perhaps not as violent as you might think.

The technique they teach is that you just fly formation.  You do NOT fixate on the basket (this is the 'drogue' part of the apparatus, which resembles a big badminton birdie).

Instead, you must position the tip of your probe about 4 feet aft of the basket, stabilize, then smoothly add throttle until contact is made.  You may need to hit the basket at a couple of feet per second relative velocity in order for it to latch.

Then you have to maintain position.  It's just formation flying, really.    The hose apparatus on the tanker measures your position fore and aft – when you are within limits for fuel transfer, a light goes on.  So, as the receiving pilot, you fly formation and maintain your position fore and aft so that the light stays lit.  When you've taken on your gas, you need to exit straight back.  Too much vertical offset can cause the basket to 'whip' as it disconnects.  You can smash a canopy this way – I've seen it happen, and it's pretty colorful.  You won't soon  live it down.


Which is better: a rotor / prop followed by a stator, or contra rotating rotors / props?

Undisturbed inlet flow provides the highest efficiency.

The single rotor with stator has a straightforward inflow; outflow will have a tangential component which is lost for thrust generation. The stator will bend the outflow back in the axial direction, but there still remain pressure increases with blade passing frequency.
The contra rotating rotor has one of the rotors in the disturbed flow of the first rotor - this second rotor will therefore have lower efficiency in transforming engine power into thrust.


Are there security checks on private flights in your own plane?

No, at least not at the Class C and D airports I have been to. There is just a locked gate with an attendant who makes sure you are either flight crew or are boarding a flight. This is to prevent the possibility of a random person walking around on the ramp.

The PIC of the aircraft, of course, may question you ("your hunting rifle is unloaded, right?") or may search your bags or body cavities or whatever he wants to do before he will let you get on. It depends on the situation. For a charter flight normally they will just verbally talk to you to make sure you aren't unknowingly bringing anything dangerous aboard.

When you fly into a country from a different country, everybody has to go through customs. So, what happens is that you all wait around in the lobby of the GA terminal while some dude from the airport examines your customs forms and goes through your luggage. Sometimes they will search the whole plane too if they want to be dicks. In smaller airports, like in a Caribbean island, you will be routed through the same customs lines that commercial passengers use.


Are there cameras which can show external components of an airplane to help pilots determine a fault?

External cameras for diagnosing aircraft issues are not used on any current aircraft. As mentioned in another answer and question, some aircraft do have external cameras, but these are more for maneuvering on the ground.

One reason for this is that cheap, high definition cameras that can stream directly to a monitor in the cockpit are a fairly recent invention. Previously, such an addition would have been fairly heavy and expensive to add to an aircraft. As mentioned, some newer aircraft that have digital cockpit displays do have external cameras for other purposes. However, even in aircraft with cameras, they are generally not used for diagnosing issues.

A lot of aircraft issues, especially with engines, are not readily visible from the outside. Internally placed sensors are still much better at detecting issues. Landing gear in particular may appear to be extended but not locked properly. Pilots are more concerned with how functional something is. Modern aircraft are equipped with hundreds of sensors and these are designed to give the pilots all the information they need about the functionality of the aircraft. These sensors are much more simple and precise than a camera. External cameras may give a misleading picture of the aircraft's state, and decisions lean towards an abundance of caution. Unless there is some extremely obvious discrepancy, it's unlikely that a camera will be trusted over the sensors.

Of course there are still incidents such as fuel leaks and fires that external cameras would help to identify. However, the aircraft sensors should be able to detect these issues once they are serious enough. Pilots also get information from passengers/crew in the cabin, and from external observers in other aircraft or air traffic control. Cameras are also limited in where they can be placed to provide a good view of things, and how well they will perform at night or in bad weather.

There may be a general case for cameras being helpful in identifying issues, but these situations are rare enough that is is hard to justify the expense. If something is enough of a risk that you need to point a camera at it, you're better off just fixing it so it's less of a risk.


Why doesn't the A380 use its outboard thrust reversers?

Because it doesn't have (or need) any.

  The A380 has reverse thrust on the inboard engines only. This saves weight and since the outboards are often way out over the edge of runways, decreases the risk of FOD.

From Airliners.net

Like all certified transport aircraft of this type, the A380 can stop from V1 on brakes alone with disks worn to minimum.

I've read that most airliners are allowed to take off even when all reverse-thrusters are inoperative. Most of the deceleration is handled by the brakes normally.

  With the Airbus A380 weighing in fully loaded at 1,265,000 pounds, you might think stopping it within a reasonable distance after landing would require a Phalanx of Heavy-duty thrust reversers.

  Truth be told, in the megaliner’s braking system, thrust reversers are the least critical components. Airliners are not required to have thrust reversers, and only the two inboard engines on the A380 are equipped with them. The decision not to install reversers on the A380’s two outboard engines saved weight and lowered the chances that those engines, which sometimes hang over runway edges, would be damaged by ingesting foreign objects.

  The two reversers do help slow the A380—but not by much. In fact, unlike the thrust reversers on most airliners, including the Boeing 747 jumbo, they do not stop the aircraft in a shorter distance than brakes and spoilers alone. They do, however, take some of the strain off the brakes and are useful if water or snow makes the runway slippery.

From Airspace Magazine

More details of braking system

  1.
   General
   The aircraft has:

  Two Wing Landing Gears (WLG) with four wheel bogie assembly and related doors
  Two Body Landing Gears (BLG) with six wheel bogie assembly and related doors
  A Nose Landing Gear (NLG) with twin wheel assembly and related doors.

  ...

  Braking
  A.    General
  Carbon brakes are installed on each wheel of the WLG and on the wheels of the front and center axles of the BLG.
  The braking system is electrically controlled and hydraulically operated.
  The braking system has four braking modes plus autobrake and anti-skid systems:

  Normal braking with anti-skid capability
  Alternative braking with anti-skid capability
  Emergency Braking (with Ultimate Braking)
  Emergency braking without anti-skid protection is also available as an alternative function of the alternate braking system.
  A park brake system that is manually set is available for the BLG only. This system can also be used to supply emergency braking.

FOD risk

A380 Landing at Farnborough Airport

A380 vs 747

  The design of the A380’s wings, with their large area, comparatively gentle sweep (33.5 degrees), and massive flaps, give the Airbus a landing speed that is 20 knots slower than that of a 747. An A380 crosses the landing threshold at a docile 140 knots and touches down, depending on its landing weight, at a speed as slow as 130 knots, about the same touchdown speed of some corporate jets that weigh 1/50th as much as the world’s biggest airliner.

AirspaceMag


A flight school won't care too much about your age if you have the required medical.  And mentally, your age is an overall plus since a flight school would generally prefer a mature individual in it because they want to teach to a 25 year old who's just building time.  The turnover with flight schools is quite high so the prospect of getting say at least 5 years out of you is another plus because they may be only getting 2-3 years out of younger instructors in the current environment (often they are basically only hanging on to get to 1500 hours under the "Colgan Rule" craziness).

I would say that that if your health is fine and shows no signs of problems over the next 5 years at least, you should definitely go for it.  You might even get a school to commit to hiring you, or at least giving you a shot (it's going to come down to how good a teacher you are), if you train with them.

With the general shortage of bodies all through the system, I don't see any downside if you really keen on doing it.  If you gain a reputation as a good teacher students will gravitate to you over the youngsters.


What is the difference between being instructed to land "as soon as possible" or "at nearest suitable airport"?

I would interpret them as:

ASAP means the plane is going to kill you. Soon. So land before that happens. Short runways, military airports, abandoned airfields, a decent highway, dry lakes (e.g. Edwards AFB), calm bodies of water (e.g. the Hudson River) are all possibilities. Do not concern yourself with operational issues like taking off again, and bureaucratic formalities like immigration will be summarily ignored. Obviously if you are near the Hudson you would try very, very hard to reach JFK, Teterboro or Newark, but sometimes that doesn't work out.

ANSA means try for a real airport considering immediate operational and bureaucratic requirements, but not beyond immediate. this could include turning around and landing at Goose Bay. Basically I'm going to punch "Nearest" on the Nav panel and make an educated choice. Most Nav sets will only show open airfields that can accommodate your aircraft. For example, Gimli would not have appeared for Air Canada flight 143, assuming they had a suitable unit back then and the power hadn't gone out.

The terms are deliberately unclear to give the pilot some flexibility - you can't predict and write a procedure for everything.


Here's how the PAPI lights work:

Depending on the angle of the viewer, a different color is seen:

Then each light is calibrated to an angle:

The good thing about this is that it's dead simple technology where very few things can go wrong: The lights have to be on and calibrated for the correct angle. The downside is that its usefulness decreases with lower visibility.

Some new systems appear to have solar panels as an off grid (and alternative/backup) power source which is sensible. Many systems today also have LED lights.

  If two airplanes with two different altitudes approach, do they see different number of white and red lights? Or are the lights set for the closer airplane?

The system is independent and passive, in the sense that it never makes contact or note of the aircraft approaching. It lights up all to all aircraft in the beam. Hence, it 'works' for all aircraft at the same time.

Some new systems feature FAROS (Final Approach Runway Occupancy Signal) giving an indication that the runway may be occupied by another aircraft by flashing the lights.

For a little information on differences between similar systems to PAPI, see this link.


Is it better to increase speed in a climb?

We know in a climb there is a vertical component opposite lift.

  Does this not in effect make the plane "heavier"?

  Does this not allow us to keep optimal AOA, and steady state (not
  curving up or down) flight, at a slightly higher airspeed when
  climbing?

No, a plane is in effect "lighter" in a climb than in level flight.

Climbing "unloads" the wing-- the lift vector is smaller in a steady climb than in level flight

For any given angle-of-attack, the airspeed must be lower in a steady climb than in level flight.

And for any given airspeed, the angle-of-attack must be lower in a steady climb than in level flight.

In a sustained vertical climb, lift must be zero, with thrust supporting the entire aircraft weight (and also overcoming drag).

Covered in detail (including vector diagrams) here-- Does lift equal weight in a climb?

Note: the question stated that the goal was to maximize "aerodynamic efficiency".  This would seem to imply that the goal is minimize fuel burn per altitude gain, or something similar.  Assuming that the engine is equally efficient at all airspeeds, it would seem that this would be achieved by maximizing the L/D ratio, in which case the concepts stated above are relevant.  Since angle-of-attack is tied to L/D ratio, any shift in the correlation between airspeed and angle-of-attack will change the airspeed that we should fly at, although the shift may be too small to notice in actual practice.  For shallow climb angles the Lift vector is really only reduced by a very small amount, and since Lift for a given angle-of-attack varies according to airspeed squared, the resulting shift in the airspeed associated with a given angle-of-attack will be quite small.

While it's good to understand the basic physics at play, we should be clear that in actual practice, it is by no means always optimum to climb at an airspeed that is lower than the airspeed corresponding to the attack that yields the maximum L/D ratio in level flight.  It depends on what parameter we are trying to optimize and on what other variables are at play.  In most aircraft, these other variables will produce changes in the optimum airspeed for climbing that completely dwarf the slight shift in the relationship between angle-of-attack and airspeed that is caused by the "unloading" of the wing during the climb.

We are more often interested in climbing at the maximum possible rate, or the maximum possible angle, than we are in climbing in the most aerodynamically efficient manner.  Particularly in aircraft with piston engines, the difference can be enormous.

In theory, for a fixed amount of Thrust, the steepest climb will be obtained at the angle-of-attack that gives the highest possible L/D ratio, but this will not be the fastest climb.  Climb rate depends on the difference between power-available and power-required.  Even though the speed where minimum power is required is actually slightly below the best L/D speed, in an aircraft with a fixed-pitch prop the speed for best climb rate is usually above the best L/D speed, because of the greater power available when the engine can turn at a higher RPM.  On the other hand, since Thrust equals power divided by speed, in a piston-engine aircraft more Thrust will typically be available at low airspeeds than at high airspeeds, despite the loss of RPM.  Since climb angle depends on the difference between Thrust and Drag, in a piston-engine aircraft the steepest climb angle typically occurs at an airspeed a little below the airspeed that yields the maximum L/D ratio, i.e. at an airspeed a little below the airspeed that yields the minimum amount of Drag.  For general aviation light airplanes with piston engines, these kind of effects related to available Thrust or Power will usually have an effect on the airspeed that yields the maximum climb rate, as well as the airspeed that yields the maximum climb angle, that completely dwarfs the effect due to the slight "unloading" of the wing by the climb angle, and the resulting slight shift in the airspeed that is associated with any given angle-of-attack.

Example-- from this Cessna 152 data sheet--

Best climb angle 55 KIAS

Best glide speed 60 KIAS

Best L/D speed-- not stated

(Theoretical best L/D speed is slightly faster than best glide speed because the drag from the windmilling or stopped propeller biases the best glide speed to be slower than the best L/D speed.)

Best climb rate 67 KIAS

Related ASE questions on the relationship between Vx, V best-glide, and Vy:

How can best glide speed be lower than best rate of climb speed??

Is Vy closer to Vbg with a variable pitch prop


Why would there be a NOTAM for an airport rotating beacon being on continuously?

The general convention is that the rotating beacon is only on at night or during IMC. The airport or ATC can choose differently. It would not be the norm and probably should be pointed out to pilots approaching the airport. It would also help identify the airport if there is confusion with multiple nearby airports of similar size and structure.


What, effectively, does a navaid being unmonitored mean?

Actually it doesn't have anything to do with voice capabilities:

5-3-5. UNMONITORED NAVAIDs
a. All VOR, VORTAC, and ILS equipment in the NAS have automatic monitoring and shutdown features in the event of malfunction. Unmonitored, as used in this order, means that the personnel responsible for monitoring the facility have lost aural and visual monitoring capabilities and cannot observe the status of the facility. It does not refer to the automatic monitoring feature.
b. When a navigational aid's operational status cannot be monitored at the controlling or monitoring facility, but all indications or reports are the facility is operating normally, issue a NOTAM placing the aid in an unmonitored status.
c. When issuing a NOTAM describing a facility as unmonitored, do not use the category of monitor, only the contraction UNMON.
EXAMPLE-
!DCA LDN NAV VOR UNMON

(Source: JO 7930.2M)
So basically it says that this VOR may malfunction without notifying a responsible party, or that a responsible party is no longer monitoring the VOR. A lot of times this is done with VOR's that are scheduled to be removed from service, they may be allowed to continue to operate but are no longer maintained.
You can still use the VOR for navigational purposes. The VOR is supposed to shut down in the event that it becomes unusable, so you can be (relatively) assured that if the VOR is operating, it is reliable and usable.


Just how do the underbanking and overbanking tendencies work?

I think your reasoning is correct. However, I would say that the change in lift due to effective AOA on each wing from yaw rate is an order of magnitude smaller than that from airspeed. At high bank angle, the wing loading is higher, resulting in more inward turn and decreased spiral stability. While the yaw-out moment from the drag is also increased due to relative airspeed difference on each wing, the effect is smaller since drag is smaller than lift.

Let's look at it more mathematically. Static spiral stability is dictated by:

$$C_{l_\beta}C_{n_r}-C_{l_r}C_{n_\beta}>0$$

where $C_{l_\beta}$ is roll moment due to sideslip, must be negative for a Part 23 aircraft; $C_{n_\beta}$ is yaw moment due to sideslip, must be positive for Part 23; $C_{n_r}$ is yaw-out moment from yaw rate, where, as you reasoned, should be negative due to increased drag on the up wing and reduced drag on the down wing (due to airspeed difference from yaw rate); $C_{l_r}$ is the roll-in moment from yaw rate, where, as you reasoned, should be positive due to increased lift on the up wing and decreased lift on the down wing (due to airspeed difference).

At high bank angle, there is increased load factor (at 45deg, it's 1.4G). Therefore, there is increased lift and induced drag on each wing. The moment arm to induce the moment is about the same for each. However, if you look at the first order effect from the speed increase, it's:

$$\Delta F=\frac{1}{2}\rho (V+\Delta V)^2SC_x-\frac{1}{2}\rho V^2SC_x\approx\rho VSC_x\Delta V$$

So all things being equal, the larger the coefficient, the more pronounced the effect. And since lift is larger than drag, it wins out. (I'm still hand-waving here a bit since induced drag is squared of lift, so it's more nuanced).

With this in mind, you can see that at higher bank, $C_{l_r}$ increases more readily than $C_{n_r}$, therefore leading to reduced spiral stability.


Is it possible to do a barrel roll in a large aircraft like a B737?

Yes, it has been done before in an even larger aircraft, the Boeing 367-80, very famously by "Tex" Johnston on August 7, 1955. This aircraft was the prototype for the Model 707.

When a barrel roll maneuver is properly performed the aircraft remains in a positive-G state, so no "inverted flight" is experienced by the aircraft. According to the International Aerobatic Club,

  The Barrel roll is a combination between a loop and a roll. You complete one loop while completing one roll at the same time. The flight path during a barrel roll has the shape of a horizontal cork screw. Imagine a big barrel, with the airplanes wheels rolling along the inside of the barrel in a cork screw path. During a barrel roll, the pilot always experiences positive Gs. The maximum is about 2.5 to 3 G. The minimum about 0.5 G.


The existing answers are, of course, correct that most current UAVs do not have much in the way of options for defending themselves against attacks by fighters. This, however, is due primarily to the design missions of most current UAVs, which are reconnaissance and attacking lightly-defended ground targets. Their mission is literally to be an expendable recon or attack aircraft, therefore it doesn't make a lot of sense to invest millions upon millions of dollars in giving them defensive capabilities. Even most normal manned recon aircraft will be short work for a modern jet fighter, with the typical use case being using actual fighters to keep enemies away from them. With a UAV, there's much less incentive to invest heavily in defending it, since they're generally much cheaper aircraft and losing them doesn't mean losing personnel.

Having said all of this, there's nothing inherent about being unmanned that makes an aircraft unable to defend itself. It's just a matter of most current UAVs being designed for use cases where they don't care all that much about defending it, so it's not worth equipping them with lots of excess available lift and thrust, extra sensors, weapons, etc.

There's nothing to say you can't design an unmanned fighter aircraft. For example, if the drone you're trying to shoot down happens to be a QF-16, then you're probably going to have a significantly more challenging mission ahead of you. The QF-16 is exactly what it sounds like - an F-16 that has been modified to act as a UAV. As such, it has the full range of evasive options available to it that you would expect from a normal 4th generation fighter aircraft, since it is one.

The U.S. armed forces use the 'Q' designator to mean that an aircraft is a UAV. This is a 'vehicle type' designator in the 1962 United States Tri-Service aircraft designation system. It is added to the F-16 designation for the unmanned F-16s, but it's also used for all military UAVs, such as the MQ-1 Predator, the MQ-9 Reaper, or the RQ-4 Global Hawk.

QF-16 flying without a pilot:


Why do some pilots call a go-around an 'overshoot'?

Looking at the Glossary for Pilots and Air Traffic Services Personnel (TP 11958E) at the Government of Canada web site, the definitions of overshoot and go-around are

  overshoot

  (1) To pass beyond the limit of the runway or landing field when
  trying to land.

  Fr: dépasser

  (2) Other expression for: go-around

and

  “Go around”

  An expression used in radiocommunications to instruct a pilot to
  abandon an approach or landing.

  Fr: « Remettez les gaz »

  go-around

  The procedure followed by a pilot who decides to abandon an approach
  or landing.

  Fr: remise des gaz

Plus, looking at various Flight Test Guides listed at the Canadian Government Air Transportation site it appears that pilots in Canadian flight schools are taught "overshoot" procedures for missed approaches (vice go-around).

Seeing as you were watching a reality TV show dealing with Canadian pilots, it is not surprising they use the terminology they were most likely taught in flight school (in Canada).


The forward ones are a ram air inlet (NACA duct) for the Environmental conditioning System (ECS) and what looks like an antenna. The aft one is an exit louver for the ECS.


Is the "auto-routing" created by online flight planning resources preferred by ATC over Direct routing when NO preferred route exists?

I did some follow up research and also spoke to an air traffic controller and I have a partial answer to this question.

If the "auto-routing" doesn't make much "sense" and there are no "preferred routes" then the probability of "getting a direct clearance would be fairly high."
The "auto-routing" logic is simply using nearest victor airways from Point A to Point B. (I'm still looking for a source for this, but it seems pretty obvious to me now).


Can an ARINC 429 controller set to receive messages on high-speed (100kHz) see 12.5kHz messages?

That is normal for an ARINC 429 receiver. The clocking for ARINC 429 is built into the transmission data, with the bipolar Return to Zero format having a Null for the last half of each bit time and requiring 4 bit times of null (0) voltage between labels. This lets the receiver adjust to the data rate automatically.


Can i get A&P course materials in .pdf format?

Go here for the PDF material.

Aircraft Handbooks & Manuals


Why do all fifth generation fighters (J20, F22, SU57) use Trapezoid wings?

Trapezoidal wings have advantages and disadvantages:

Better performance than delta wings at transonic speed
Good stealth performances
Flaps can be easily used.
drag reducing
better Lift/Drag ratio than delta wings

The problem is that they stall at much lower angles of attack than delta wings.

Edit:this problem is overcome using leading edge,LERX,and/or canards


Is there any size of tethered kite that is regulated by the FAA?

As one of my instructors was fond of pointing out, there's pretty much a regulation for everything -- in the US kites and balloons would be covered under FAR part 101 which is pretty short and to the point as far as government regulations go.

The big rules regarding kites/balloons kick in for a kite "over 5 pounds" or a balloon "over 6 feet in diameter / 115 cubic feet of gas capacity", and are:

You have to keep them at least 500 feet below any clouds.
You have to keep them less than 500 feet above the ground.
You must be at least 5 miles from the boundary of any airport.

If your kite/balloon is going to be more than 150 feet above the surface you're also supposed to coordinate with the closest ATC facility (who would theoretically put out a NOTAM saying "John Doe is going to be flying a kite/balloon/thingy here, between these hours. Please try not to hit it.")

There are also some lighting requirements (if you fly the balloon/kite at night), and visibility requirements (but really, who wants to fly a kite in less than 3 miles visibility? That seems like pretty lousy kite weather.)

As a favor to your local pilot community (and to prevent having your wayward kite dragged off by a Cessna on short final) it's probably best to observe the three "big rules" above regardless of the size of your kite - a 6-ounce piece of balsa and cellophane can still make a lot of people's days more interesting if it appears in an unexpected location.


At which point in scale reduction do slats and flaps become unnecessary?

Putting slats and flaps on a 10 cm model is extreme, but would add a touch of realism for the serious hobbyist.

  At which point in scale do slats and flaps become unnecessary?

We turn to the lift equation:

$Lift$ = Air density x Area x Lift Coefficient x Velocity$^2$

$Weight$= $Lift$ for steady state flight so we derive:

$Weight/Area$ = Rho x Lift Coefficient x Velocity$^2$

In terms of considering the need for slats and flaps, the primary factor is the difference in landing and cruising speed.  In an airliner, the difference can be 350 knots! (Maybe a little less, considering Rho at higher altitudes, indicated airspeed).  For a Storch, around 60 knots,  for a tiny model with light wing loading:  maybe 7 knots.

When we compare $Kinetic$ $Energy$ = 1/2mV$^2$, one sees a scaled down model with low airspeed and very little mass makes for a landing roll-out of only a few feet, whereas the 400 ton airliner at 150 knots needs over a mile to stop.  The faster, heavier plane needs to slow down as much as it can before touchdown.

Also from the lift equation we can derive that increasing coefficient of lift, by increasing AOA, or by reconfiguring the wing, only increases lift in a linear fashion, whereas lift increases with the square of velocity.

The need for slats and flaps really depends on how slow you need to get to land safely.
So does greater runway length, which allows for a slightly faster approach speed.

Further more, we find one aspect of the Fi 156 Storch rarely discussed, its 240 hp Argus AS 10 V8 and it's variable pitch prop.

This shows the designers went to great lengths to provide adequate power to keep flying in spite of the tremendous drag the slats and flaps create.  It was a price to pay for increasing STOL performance, and illustrates why aircraft perform far better "cleaned up" at Vy.

Note of interest:  the same engine was used with the Bf 108 "Taifun", resulting in a cruise speed 50 knots faster, landing around 45 knots.  Both planes were of similar weight.