From this copy of the flight manual for the 737:

  Glide Slope Pointer and Deviation Scale

  ...

  At low radio altitudes, with autopilot engaged, the scale turns amber
  and the pointer flashes to indicate excessive glide slope deviation.

  Each pilot’s deviation alerting system self-tests upon becoming armed
  at 1500 feet radio altitude. This self-test generates a two second G/S
  deviation alerting display on each attitude indicator.

And for the localizer

  Localizer Pointer and Deviation Scale

  ...

  At low radio altitudes, with autopilot engaged, the scale turns amber
  and the pointer flashes to indicate excessive localizer deviation.

  Below 1,000 feet AGL, with LNAV engaged and LOC armed, the localizer
  scale turns amber and the pointer flashes if the localizer is not
  captured.

  Each pilot’s deviation alerting system self-tests upon
  becoming armed at 1500 feet radio altitude. This self-test generates a
  two second LOC deviation alerting display on each attitude indicator.

What is interesting is that the pilot seems to be right on slope and right on the localizer so I would presume it is NOT flashing as a result of excessive deviation.


Why are the angle-of-attack sensors on most airplanes mounted on the forward fuselage rather than at the wing roots?

Would installing the AOA vane (or, in general, sensor) at the wing root be more accurate than installing it near the nose? No, it wouldn't. In fact, it may be slightly worse due to the larger upwash at the wing leading edge and the vane protrusion may even negatively interfere with the wing aerodynamics.

Traditionally, AOA measurements are used for stall warning and, if required, stick pusher. During flight tests, the thresholds for stall warning activation (and stick pusher activation) were calibrated to the local AOA measurements from the vanes to satisfy the certification requirements, while minimizing $V_S$/$V_{SR}$ to maximize performance.

In FBW aircraft, if the control laws have AOA dependency, the control law would typically be designed with aircraft AOA (a.k.a free-stream AOA) as specified in wind tunnel and/or CFD. Therefore, the local AOA measurements would need to be corrected to the aircraft AOA before being consumed by the control laws. Answer to this question outlines the methods for such correction during flight test.

Addendum:

There are a number of other AOA measurement devices besides vane and Smart Probe (used on A220 and E170, E190). The most common ones are leading edge orifices or tabs used on GA aircraft (thanks @JanHudec for pointing out). These operate by sensing the movement of the stagnation point as AOA increases. The downside, of course, is that the stagnation point associated with the required margin to stall is different at varying Mach numbers and across high lift configurations.

This NACA report contains a number of wing-mounted stall warning devices tested in the last century.


Why it doesn't matter if tail produce lift or downforce for neutral point position?

The neutral point is the lengthwise location of the moment reference point where the pitching moment will not change with a change in angle of attack. It can be defined for a wing alone or for the whole airplane.
Of course will a change in the incidence of the tail also change the pitching moment around the neutral point. But that is besides the point: The special characteristic of the neutral point is its neutrality regarding to changes in angle of attack.
Mathematically speaking: If the slope of the pitching moment over angle of attack is zero, the reference point for this moment is the neutral point. If you pick a different point ahead of the neutral point, the slope will become negative (which characterizes a stable configuration) and vice versa. The neutral point depends on the derivative of the pitching moment over angle of attack, so the absolute value of it doesn't matter. It's the change with angle of attack that counts.
If the center of gravity coincides with the neutral point, the airplane has neutral longitudinal stability. Hence the name.
This all is valid only in the range of attached flow. If there is massive separation, all bets are off.


The picture in your question shows the answer: Most lighting in the cabin is done indirectly, so you don't see the light source directly. Instead, light is reflected off the cabin interior. If you would paint that interior in gaudy colors, you would have undesirable effects. Colored surfaces absorb some wavelengths, so the brightness in the cabin is reduced. Plus, the selective reflection will shift the color of the light.

Newspaper and magazine paper would not be white anymore, but have the color of the cabin interior. As @mins correctly points out, the brain can compensate for this. It will, however, make it difficult to read text printed in the color of the cabin interior because it would no longer stand out from the background.
The color pictures in the magazines would look funny. If you now think people could switch on the reading lights: Note how few passengers actually know how to operate them.
The food you get served would look funny. It is already not a pleasure to look at in most cases, but in colored light it gets even worse.

While it might be fun momentarily to be in a room with mood lighting, being exposed to this one color for the full length of the flight without a possibility to escape (except for closing your eyes) will offend most passengers.


A rubber engine is not to be confused with a rubber motor (a rubber band which is twisted in order to store energy which can be released when the rubber band untwists. This type of engine is good for short energy bursts in small model airplanes).

A rubber engine is an engine deck (tables of engine data) which can be scaled according to your needs. In a way, you stretch one parameter of the data like a rubber band, and all other parameters change accordingly. In most cases, you adjust thrust to your needs and the scaled engine deck will produce mass, size and fuel consumption for the most likely actual engine with the given thrust. This is very helpful in the initial stages of engine design when you search for the smallest possible airframe to fulfil given mission requirements.


Is there a V speed for the point an aircraft starts an ascent at 0 angle of attack?

No, there is no V-Speed associated with zero angle of attack, nor is climb associated with angle of attack. Since zero angle of attack does not directly translate to minimum drag for a production aircraft in operation, it is not a meaningful performance gate, which is what V-Speeds are designed to represent.

However, this is not to say that having a zero flow incidence against the fuselage is not desirable:

If the body-axis is aligned with the fuselage longitudinal axis, it would be desirable from a passenger comfort standpoint to fly at zero AOA during level cruise. We don't want to have an inclined martini glass for the whole duration of the flight.
Non-zero flow incidence against the fuselage does create drag. It would be desirable from a performance perspective to decrease any form of drag during cruise or climb.

This is achieved during aircraft design. The wing setting angle against the fuselage is tuned such that the average operational flow incidence angle against the fuselage is minimized.


Is there a use scenario for the Detote value?

On 747-100/200 aircraft, the "detotalizer" was on the flight engineer's panel. The image below is, I believe, from a 747-400 because those on the -100/200 aircraft were mechanical digits rather than electronic, but I couldn't find an image of the earlier version.

Before engine start, the f.e. set the aircraft gross weight and the total amount of fuel. From that point, the instrument kept track of of your decreasing gross weight and fuel quantity.

The amount of fuel showing on the detotalizer was considered to be more accurate than that shown by the fuel quantity gauges, and thus was controlling for en route flight decisions.

Besides quickly and accurately giving the amount of fuel remaining in general, it was critical to redispatch operations (sometimes called reclear). See the "Reserve reduction" section of the Wikipedia article on flight planning for a detailed redispatch explanation.

Basically, though, redispatch allows you to legally get to a destination for which you can't (or don't want to) carry enough fuel to to reach that destination with the required reserve fuel. What happens is that you're dispatched to a destination short of your desired destination. Then, nearing the destination to which you were dispatched, you are then redispatched to the desired destination.

An example. I used to fly JFK to Tel Aviv, a flight that always required a redispatch in a -100 and sometimes in a -200. The flight was usually between 10 and 12 hours, depending on winds, how you hit the North Atlantic track system, and routing through Europe. Let's say the expected fuel burn was 275,000 lbs. The dispatch fuel requirement would be that plus 5% reserve (from memory, might have been a higher percentage). So, to be legally dispatched to Tel Aviv, you had to have 288,750 lbs of fuel at takeoff. But let's say the most fuel you could load (or wanted to) was 280,000 lbs.

No problem. You dispatched to Athens, well short of Tel Aviv, and for which the fuel requirement was considerably less than the 280,000 lbs you had on board. You used a route that took you over the Mediterranean on the way to Tel Aviv through an intersection abeam Athens. You had two flight plans aboard: one from JFK to Athens and one from that intersection to Tel Aviv. The fuel requirement for the second one was the burn from the intersection plus 5%. Thus the reserve fuel requirement for redispatch was 5% of something like 30,000 lbs (burn from the intersection to Tel Aviv) versus 5% of 275,000 lbs (burn from JFK to Tel Aviv).

Coming up on the intersection, you looked at the detotalizer. If it showed at least the required legal fuel on the second flight plan, you called the company and were redispatched. If it showed less, you would turn left at the intersection and refuel at Athens. As I remember, I never had to do that, although, truth be told, there was the occasional fudging of a hundred pounds or two, maybe three, but never more than that.


Generally, smoke comes from incomplete burned fuel.

Normally, a jet engine burns a very lean mixture (due to turbine temperature constraints). Nevertheless, getting all the fuel to burn is a considerable challenge, primarily because the air/mixture flows faster in the engine than the flame front. So in order to provide stable burn, many tricks come into play: the combustion chamber expands after the compressor; there are special vortex generators that force the mixture to backflow and circulate; the air may be fed in stages along the chamber, etc.

This complicated gas dynamics is difficult to optimise, especially in the 70s when MiG-29's engines (RD-33) were designed. What usually happens is that there are pockets of over-rich mixture in the combustion chamber, and the extra fuel decomposes due to high temperature before it has an opportunity to burn.

From what I know, RD-33MK got a redesigned combustion chamber (amongst other things), but what exactly the changes are is hard to say. I can speculate that the source of the original problem was that RD-33 had an early example of the annular combustion chamber, which was not well studied then. But the problem was bad enough to make MiG-29 more easily detectable in visual fight.


How are large cargo aircraft loaded at airports?

They will be loaded/unloaded on the ramp somewhere,

In the case of a facility like the one UPS owns in Louisville KY. they will have a large amount of ramp space in and around the facility which is on the field.

(source)

The aircraft will pull to the facility as they would a gate and be loaded there

(source)

In the case of just more generic cargo loading and unloading at an airport where no shipper has a facility the airport authority or FBO may have a facility set aside for cargo like the one at JFK. You can find a full list of the airlines/operators who have facilities at JFK here as an example. You can find a full map of the JFK cargo facilities here.

Keep in mind that some cargo will go on passenger planes and may be loaded at the gate. Along with everything else. In this case the cargo will be accepted and sorted (most likely at one of the above example buildings) and then towed over to the aircraft.

Airport fees here in the states are often charged by weight so the fees to the field will be judged on that. The fees for the cargo operations will most likely depend on what you need done such as loading/unloading, storage, customs, refrigeration, live stock services etc. I dont see any explicit prices listed but here is another one of JFK's cargo handlers CAS, I would assume you could contact them if you wanted some pricing on a given transaction.

I would not think the reinforcement is any different than anywhere else, a fully loaded aircraft be it cargo or people is the same weight.


Do aeroplanes have to balance torque like helicopters?

A single engine plane can suffer from control problems due to torque.

An early famous example was the Sopwith Camel

As others have pointed out, torque effects have to be countered using the normal aerodynamic controls available to the pilot. Some aircraft had extra-large ailerons because of this issue.


How close would another aircraft have to fly to warrant a sudden big altitude drop to avoid collision

Most modern aircraft are equipped with TCAS (Traffic Collision Avoidance System) which is a last resort to avoid collision if all other safety nets have failed and two aircraft have gotten too close.
A TCAS can generate an RA (Resolution Advisory) which is a distinct message instructing the pilots what to do - typically either "CLIMB" or "DESCEND". When an RA is generated, the pilots have to comply with it immediately, regardless of all other instructions, unless it directly puts the aircraft in danger. In case of two conflicting aircraft, the TCAS system of each aircraft will communicate with the other, so for example, for two flights on converging courses, one will get a "CLIMB" instruction and the other a "DESCEND".
As for timing:

The maximum generation time for an [...] RA is 35 seconds. The time scales are shorter at lower altitudes (where aircraft typically fly slower). Unexpected or rapid aircraft manoeuvre may cause an RA to be generated with much less lead time. [...] The effectiveness of an RA is evaluated by the ACAS equipment every second and, if necessary, the RA may be strengthened, weakened, reversed, or terminated.

From SKYbrary
Essentially, this means that an RA will only be generated if two aircraft are calculated as being very close to colliding (within 30 or so seconds of collision). Note that the actual distance between the two aircraft does not matter in this regard - calculations are based on "time until impact". Two aircraft on slightly converging courses, closing slowly, can get much closer before an RA is triggered compared to two fast aircraft meeting head on.

As for the specific incident you are talking about, it is unclear if a TCAS RA was generated. Normally, fighters intercepting an aircraft will turn off their transponder (at least partly) to disable TCAS, with the specific purpose of avoiding such alerts (since they intentionally want to fly close to the other aircraft).
Even if we consider the "1000 metres" claim to be correct, it is not possible to say if that is "too close" or not. If we are talking 1000 metres vertically, that is more than 3 times the normal required separation of 1000 feet. However, 1000 metres horizontally would, in many (but not all) cases, be too close.


Can a single engine on an A320 provide wing anti ice?

It would probably be a single point of failure if one engine wouldn't be enough to deice both wings.

For this reason there is a cross bleed selector so that the remaining engine can feed the wing on the opposing side.

Here is a link to a computer based training video of the A320 explaining that a single engine bleed is enough for both wings but not for both air conditioning packs and wing anti ice at the same time. So to use have wing anti ice with a single engine you need to turn off one pack and enable cross bleed.


What happens aerodynamically when we trim an aircraft?

It depends on the aircraft in question, the arrangement of the lifting surfaces, and how they are designed to ensure both static and dynamic stability.

For a simple case, well consider a traditionally designed airplane with a wing set placed approx midway along a fuselage with a horizontal tailplane at the empennage.

The design provides both good static stability and good dynamic stability.

It does so by placing the center of gravity (CG) ahead of the center of lift (CP) for the main wing and causing the tailplane to produce a downwards lifting force to counterbalance the moment caused by the distance between the CG and the CP.  While this is not as efficient a lifting arrangement as other designs like a canard foreplane, it forms a naturally stable platform in terms of longitudinal stability.  The airplane will remain stable only if these two moments cancel each other out causing the Net moment about the CG to be zero AND if the design naturally returns to a zero moment about the CG when dynamically changing speeds and attitudes.

For trimming, here we will only consider pitch trim for longitudinal stability.  An airplane trimmed for cruising at a specific airspeed and a particular altitude will have a net longitudinal moment about the CG of zero.  If the airplane increases its airspeed, the tailplane arrangement is designed to increase its downward force, creating a nose up pitch moment.  This in turn decreases the airspeed causing the the downward tailplane lift to decrease again, resulting in the nose pitching forward again until an equilibrium of forces and moments is again attained, which will be at the original airspeed for which the plane was trimmed for.  To maintain straight and level flight at a higher airspeed the trimming action will decrease the amount of lift that tailplane produces at the new selected airspeed, again resulting in a net longitudinal moment about the CG to zero.

Longitudinal trimming can be accomplished several different ways the first of which is a design feature which can alter the angle of attack of the tailplane in flight to change the lifting force it creates.  This is common on jetliners and other large aircraft but not common on light aircraft due to the excess weight of the structure.  Another option for smaller aircraft is the installation of a movable servo or antiservo tab on the elevator surfaces.  These tabs force the elevators to a new neutral position, again altering the lifting force from the tailplane and creating a trimmed condition.

In regards to the original question the net CP, that is the combined location of both the center of pressure of the wings and the center of pressure of the tailplane will coincide with the CG on the longitudinal axis of a trimmed airplane.  If the airplane accelerates, the NET CP will move fwd of the CG, causing the airplane to nose up, without additional trimming to bring it back.  Similarly, when the airplane decelerates, the NET CP will move aft of CG, causing the aircraft to nose down without additional trimming.


Is there a model to calculate fuel burn over the Atlantic ocean given an arbitrary aircraft identification?

I am sure every airline has such a model, which will include actual wind and temperature information, but it will contain proprietary data which is not publicly available, unless you have a proven interest and signed an NDA with the airframe and the engine companies. Boeing is actively marketing such software to it's customers. For first-order estimates, Federico's comment is a good start, but you will still need fuel flow and L/D values.

A range of similar software exists, but here the quality of the output depends mainly on the quality of the aircraft and engine models. While Boeing should know their aircraft well, the authors of independent software like Piano or APP have to guess the right values, but still sometimes such tools will be precise within one percent. Piano even offers a free version called Piano X, but you will need to burden yourself with a Windows installation to run it.

If you need even more precision, there are commercial packages which do this, first of all J2 Aircraft Dynamics. But this does much more; fuel flow is only a tiny aspect of the full package. Eurocontrol is supporting BADA, which is a tool for computing aircraft trajectories, but it can also compute the full flight and contains an extensive set of detailed aircraft datasets. Access to BADA is restricted, however, and you will need to acquire a license.

If you want to assemble your own tool, JBSim would be a good start. Write a wrapper which calls JBSim repeatedly and keeps track of the aircraft trajectory, and integrates the flight parameters along the way. But you will still need to get the aerodynamics and engine data from somewhere.


Can surface roughing effects on an airfoil Reynolds number be quantified?

Roughness has no influence on the Reynolds number. It will, however, help to trigger a laminar-turbulent transition. That is the reason for dimples in golf balls. Also, roughness will increase the friction drag in turbulent boundary layers.

Flat plate friction diagram (picture source). Note the horizontal lines: They show that drag does not drop any more with increasing Reynolds number once the surface roughness exceeds a certain value. Roughness is given here relative to the chord length as $\frac{\epsilon}{l}$, with $\epsilon$ being the mean height of the roughness and $l$ the chord length.

The diagram only starts at Re = 100,000, so it is clearly outside the range of your application. If you sand your wooden surface with fine grit sandpaper, I don't expect that the remaining roughness will increase drag. At those Reynolds numbers it might be advantageous to add a trip wire in order to induce a transition to turbulent flow – see the golf ball example.


A "fully-stalled take-off" is an attempted takeoff where the elevator has too much authority. This can cause the aircraft to rotate to an excessive nose up attitude, which can exceed the stall angle of attack, before takeoff speed is attained.
Ventral fins were added to some B707s to improve yaw control, and prevent over-rotation. Over rotation which could lead to a "full stall at takeoff".
https://en.wikipedia.org/wiki/Boeing_707

The British Air Registration Board refused to give the aircraft a certificate of airworthiness, citing insufficient yaw control, excessive rudder forces, and the ability to over-rotate on takeoff, stalling the wing on the ground (a fault of the de Havilland Comet 1). Boeing responded by adding 40 inches to the vertical stabilizer, applying full instead of partial rudder boost, and fitting an underfin to prevent over-rotation.


Is there a wake turbulence difference between B737s?

According to the Wake Turbulence Re-categorisation, the older 737's are Lower Medium, while the 737NG is Upper Medium.

High lift (weight) and low approach speed increase the wake turbulence. The newer 737's are heavier, while their approach speeds are not much faster than the older models.

The 757's are Lower Heavy. See: What is the cause of unusually strong wake turbulence from the 757?


There are various standards out there and ways of doing things but DO-178C is the latest iteration of the document that outlines how real time avionics are to be programed. Certifying agencies like the FAA may have their own supplements/orders that specify specifics for a given jurisdiction, for example here is the FAA's order.

Avionics themselves often connect over the ARNIC data bus.

Many avionics and aircraft companies design their own OS's when they needed them for real time applications

  Honeywell, for example, created the digital "engine" operating system
  (DEOS) and Rockwell Collins, the virtual machine operating system
  (VMOS), which it engineered from an earlier LynuxWorks product in the
  late 1990s. Collins licensed the changes back to LynuxWorks in the
  2002-2003 time frame, and LynuxWorks now offers the new version of the
  software as LynxOS-178.

WindRiver did the OS for the dreamliner

  Smiths Aerospace chose Wind River Systems' VxWorks 653 RTOS for the
  B787's common core system (CCS), a cabinet that will host 80 to 100
  applications, including Honeywell's FMS and health management software
  and Collins' crew alerting and display management software.

There is a great podcast on designing spacecraft software (basically the same use case) that you can find here.

Its worth noting that the cost to certify avionics tends to be quite high (under the FAA) so code and methodology dont change all to much. Once avionics get certified companies have a way of continuing to make them for a very, very, very long time.


How do you contact ATC if you want to do RC flying in the US?

Any specific verbiage that needs to be used?

Just tell them you will be flying an RC aircraft with 5 miles of their airport. You should have on hand the location you have in mind. Preferably, know the distance and bearing from the airport, like "3 miles to the southwest". Even better would be a more exact bearing and distance from the airport or a nearby VOR. Also know what max altitude you expect to be at. See the related question for a more thorough description (about NOTAM info, but the same general idea applies): How do I submit a NOTAM?

And if you are wondering how to get in touch with the tower: How can I find telephone numbers for FAA ATC facilities?

  Can the request be denied?

In general I would say yes. One of the main rules of RC flying is to not endanger manned aircraft. If ATC thinks your selected location will break that rule, then you shouldn't fly there. That would be part of why they ask you to contact ATC in the first place.

However, the wording is "provides the airport operator and the airport air traffic control tower...with prior notice". It says nothing about receiving approval, clearance, or permission from them. So I'm not sure if you are breaking any regulations if they say no and you fly anyway, assuming you don't break any of the other rules.

  Does anybody have any actual experience doing this?

Not me at the moment. I will try to update if that changes.


What is this molten metal coming from the engine of an Avro RJ 100?

I do not see anything in your photo, apart the engine that looks perfectly normal.

Anyway
here it is written that the fuel burns at up to 2000 degrees Celsius and the temperature at which metals in this part of the engine start to melt is 1300 degrees Celsius. Hence the metal may melt if something goes wrong.

Avro RJ100 has four engines so should be able to land with one inoperative. From the question I have just asked myself, it will not be qualified as accident so may not get widely known.


Why is the velocity squared in the lift equation?

Newton's second law is:

$$F = ma$$

The $m$ass in the lift equation is of the fluid's, mass times velocity is the fluid momentum. So the equation can be written as:

$$F = {\Delta}(mv)/{\Delta}t$$

Rearrange that equation and it becomes:

$$F = \text{constant}
\cdot
(m/t)v$$

Mass over time is the mass flow rate:

$$m/t = {\rho}vA$$

So we end up with:

$$F = \text{constant}
\cdot
{\rho}vAv$$

Which is:

$$F = \text{constant}
\cdot
{\rho}v^2A$$

Add $A$ to the constant:

$$F = \text{constant}
\cdot
{\rho}v^2$$

Reference: NASA


What altitude should you cross DBIGE at on the PALLEY FIVE Departure (SID)?

As it reads:

....on assigned transition, maintain FL190, expect filed altitude 10 minutes after departure.

If no instructions are received after 10 minutes, remind the ATC. From the FAA FAQ:

Q. I am cleared to "Climb Via SID". What if there is a published altitude restriction at a fix that is higher than the charted "Top Altitude"?
A. You are only cleared to the charted "Top Altitude" contained in the narrative of the procedure, unless ATC assigns a different altitude.

From the AIM:

SIDs will have a "top altitude;" the "top altitude" is the charted "maintain" altitude contained in the procedure description or assigned by ATC.

Consider a charted top altitude as the equivalent to a verbal "except maintain." As "except maintain" also does not cancel the restrictions below it. I believe this makes it easier to remember.


Do jetliners carry radar that can detect other aircraft?

Radar that can detect, resolve and track small targets as opposed to large areas of water (raindrops) has to be a lot more powerful and sophisticated, especially in ye olden tymes of the 50s and 60s when weather radar was becoming a thing and the search for a practical collision avoidance system was underway.
When the effort that eventually became TCAS got started in the late 50s following several notable midairs, on-board target detection was one of the early proposals but was rejected by the industry as too expensive and time consuming to develop (where to put the more powerful system with its larger antenna for starters).
Once TCAS was perfected, made possible by the development of Mode C altitude reporting by transponders, you got 95% of the benefit (because only non-Mode C-transponder light planes were still a risk - a very minor factor overall once Mode C was pushed out to GA aircraft) without a crazy expensive addition of on-board target detection and tracking radar PLUS a weather radar.


What is this turn called and how is it performed?

The maneuver is called a "breakaway maneuver" or simply a "break", it's also sometimes colloquially referred to as "peeling off" in the context of aircraft leaving formation. You can see it more clearly in this video:

This is a standard maneuver used when disengaging from a intercepted target, or as a way to safely exit formation flight ensuring that the departing aircraft is clear of the rest of the formation group.
It also has tactical advantages as seen in the photo you posted (when being tracked by an infra-red/heat-seaking missile, dropping flares and a hard breakaway is one technique used to convince the missile that the flare is actually your engine, by getting your real heat source out of its "line of sight" quickly).

Aerodynamically the breakaway maneuver is nothing more than a steep turn: Roll the aircraft into the desired bank, setting power and pitch up to maintain your altitude and airspeed in the turn as desired.
A Cessna 152 flying in formation could break away using the same maneuver, though the bank angle and airframe loading (G forces) would need to be maintained within the aircraft's limitations.

The primary difference with fighters and attack aircraft is that the bank angle is dramatically steeper (in the extreme, a 90-degree "knife-edge" bank) and the turn much tighter because these aircraft have the excess power (thrust) required to sustain flight in that configuration and are sturdy enough to withstand the G loading induced by a "hard pull" in the breakaway maneuver. The abrupt wings-up turn along with the nice roar you get advancing the throttles makes the maneuver an impressive one for airshow crowds to watch.


How far can a 777 fly with just one engine at altitude?

Flying with only one of two engines will not increase range, but reduce it. A gas turbine consumes fuel in proportion to the mass of air moving through it, so with increasing altitude consumption decreases proportional with air density. Thrust goes down with density as well, so thrust-specific fuel consumption is roughly constant (actually, the engine becomes more efficient with altitude due to the lower air temperature, see Carnot cycle for more on that).

Generally, a jet transport wants to fly as high as possible for maximum range. Its cruise altitude is limited mainly by the thrust available from all engines. If the pilot shuts one down, the aircraft needs to fly much lower until thrust has increased sufficiently to overcome drag. Since friction drag is also proportional to air density (and the square of flight speed), the aircraft has to fly much slower at that lower altitude, which cuts range since the fuel consumption of the single engine is now roughly what both consumed at altitude, but now the aircraft covers less distance in the same time. In addition, the pilot has to compensate asymmetric thrust with rudder deflection, which again increases drag.

Short answer: The aircraft will not go MORE miles, but FEWER.


What is the average number of daily flights for all types of aircraft in use worldwide?

As mentioned above there are a significant number of aircraft that have no way of being recorded. However, we can make an educated guess. According to the FAA, they support; "Every day, the FAA's Air Traffic Organization (ATO) provides service to more than 42,000 flights" - https://www.faa.gov/air_traffic/by_the_numbers/. These numbers would be aircraft with flight plans, controlled airport landing & takeoffs, flight forwarding, vectoring, etc.

Probably (a guess) at least as many general aviation aircraft do training, VFR flights, helicopters (i.e. ranch cattle herding), balloons, scientific, skiing, hunting, sightseeing, gliders, ultralights and maintenance flights without filing a flight plan or interacting with ATC.

So that puts the US at about 80,000 flights per day. The US is approximately 5% of the world population and if we use that as a basis for calculating flights, then there are about 1.6 to perhaps 2 billion flights per day, including all forms of aircraft.

This is interesting - we might at first conclude 1/4 of the earths population is flying on any given day. This would be a wrong assumption because many passengers embark on several flights to reach a destination each day. For an example, a sightseeing cross country trip might include 3 or 4 stops that include re-fueling and eating, or restroom breaks. But, this is still a staggering number of people flying each day. Conservatively, perhaps 1 out of every 50 to 100 people are traveling by air each day!!!


Is airflow ever laminar in the boundary layer, near the wing leading edge?

In still air every boundary layer starts laminar. How soon it transitions to a turbulent boundary layer depends on:

the local Reynolds number,
the pressure gradient,
wing sweep and
disturbances like bugs, rivet heads or turbulators.

Flat plate flow (without pressure changes) normally transitions at a Reynolds number of around 400,000. If the flow is accelerated, all speeds in flow direction increase while cross flow will not be affected, so a laminar boundary layer in accelerating flow is stabilized. On modern gliders the lower surface is laminar in excess of 80% chord at higher angles of attack, which can correspond to a Reynolds number of 5,000,000 or more when transition eventually occurs.
On the other hand, a pressure rise in flow direction corresponds to a deceleration in flow direction, so any movements perpendicular to the flow direction will grow relative to the flow speed, and as a consequence the turbulent transition occurs rather quickly. Upper side flow past the suction peak near the leading edge is a prime candidate for transition, and that is what causes flow around the "traditional airfoil" to become turbulent earlier. The graph in your question is misleading because the lower side flow of the traditional airfoil should be as laminar as that of the P-51 airfoil if the surface smoothness of both is comparable.
How laminar was the P-51 wing?
At the flight speed of the P-51 very little laminar flow was left; the full effect of laminar airfoils can only be exploited at Reynolds numbers below 5,000,000. At higher Reynolds numbers it needs progressively steeper gradients to keep the boundary layer laminar, such that the range of angles of attack where a long laminar boundary layer is possible on both sides of an airfoil (the laminar bucket) gets smaller and smaller.
The "rooftop" distribution of the 6-digit NACA airfoils did help, though, because it gives them a higher critical Mach number than the "peaky" distributions of earlier airfoils. The suction peak near the nose of older airfoils will lead to local supersonic flow at a lower flight Mach number, and increased drag from the shocks which would follow. Most important for its low drag, however, was the very smooth wing surface of the P-51 with no gaps ahead of the spar. See this rec.aviation.military post for details.
Influence of Sweep
Wing sweep will also make it hard to maintain laminar flow. As explained here, on a swept wing only the speed component perpendicular to the wing will be affected by it, so the accelerating flow past the stagnation point will curve inwards on a sweptback wing. At the same time, viscosity will slow down the flow near the wing skin. The consequence is a twist in the speed distribution over the boundary layer, which destabilizes the laminar flow and leads to early transition.
A C-172 with its four-digit NACA airfoil has the peaky upper surface which will trip the boundary layer very early on the upper surface. On the lower surface laminar flow will last a little longer but will be destabilised by gaps in the surface, so most of the flow on the C-172 is turbulent. On an airliner the Reynolds number is in the tens of millions, so transition will be very early and very little laminar fraction remains. This is mostly found near unswept leading edges like the engine nacelles. Only with advanced technologies like boundary layer suction will it be conceivable that a larger part of an airliner wing can be kept laminar.
Transition and Separation
Laminar separation sometimes happens when the flow separates shortly after negotiating the nose, like on a five-digit NACA airfoil or an undimpled golf ball. This leads to an abrupt stall and should best be avoided. Normally, the boundary layer transitions into the turbulent state and stays attached until the turbulent boundary layer separates, either at the trailing edge, or progressively further ahead of it when the airfoil stalls.
Sometimes, transition happens in a laminar separation bubble. The decelerating flow past the suction peak is slowed down by friction near the surface, and both effects combine to bring the flow to a standstill at some point. The boundary layer thickens, such that the pressure rise is momentarily suspended, and speed oscillations in the boundary layer get amplified such that cross flows become more intense, mixing outer and inner parts of the boundary layer. The speed profile becomes fuller and the flow near the wall picks up speed again, such that the separation disappears and pressure rise resumes.
Below I plotted the XFOIL results for the pressure distribution around the HQ-17 at Re = 1 Mio (the HQ-17 is used on the ASW-22 Open Class glider, for example). The dashed, black lines show the inviscid pressure while the colored lines show the viscous flow results. On both sides you will see a kink in the colored lines - this is where the laminar separation bubble is.

When the flow separates, the pressure line becomes horizontal. After transition it jumps back down near the inviscid line, which shows how much steeper the pressure gradient is that a turbulent boundary layer will tolerate. Reattachment is complete when the steep pressure rise has brought the local pressure back near the inviscid level. Note in the airfoil plot at the bottom that the boundary layer thickness peaks where the separation bubbles are.
Yes, the boundary layer is laminar before and into the separation here. This phenomenon occurs at the scale of model aircraft, gliders and small GA aircraft (100,000 < Re < 5,000,000) but is absent at higher Reynolds numbers because then the transition happens before the laminar flow separates.


What's the formula to calculate static air temperature?

is there any other formular/way to calculate static air temperature using only mach/tas/altitude ?

No.

Mach (or TAS) can only give you the ratio between total and static air temperature, as seen also on Wikipedia:

$$ \frac{T_\mathrm{total}}{T_{s}}={1+\frac{\gamma -1}{2}M_a^2} $$

Knowing the Mach number will give you the quantity on the right hand side of the equation ($\gamma$ is constant and is about 1.4 for dry air). If you cannot measure one of the two quantities on the left hand side, you cannot derive the other.

You could in theory derive the temperature from a measurement of the static pressure, if somehow you could also measure the air density, but that's not using only "mach/tas/altitude" as you requested.

A final option is to derive the temperature from the standard atmosphere model using the altitude, but that might not be a number reliable enough for your purposes.


How can the Airbus A319 accommodate 156 passengers with overwing emergency exits?

Yes, airlines can use a 156 seat layout in the A319. See Allegiant's layout.

The FAA type certification for the A320 series can be found on the site here, under TCDS A28NM. For the A319:

  Maximum Passengers:
  145
  See note 11 and 18
  ...
  Note 11:
  If modification 32208 is embodied in production on A319 airplanes, the aircraft is eligible for maximum capacity of 160 passengers. This modification consists in structural and system provision for the installation of second pair of overwing emergency exits.

The certification basis section g states that the design complies with the following regulations:

25.811(e)(3) Type III emergency exit marking.
25.813(c) for emergency exit access

The regulation from section 25.813:

  §25.813   Emergency exit access.

  (c) The following must be provided for each Type III or Type IV exit—(1) There must be access from the nearest aisle to each exit. In addition, for each Type III exit in an airplane that has a passenger seating configuration of 60 or more—

      (i) Except as provided in paragraph (c)(1)(ii), the access must be provided by an unobstructed passageway that is at least 10 inches in width for interior arrangements in which the adjacent seat rows on the exit side of the aisle contain no more than two seats, or 20 inches in width for interior arrangements in which those rows contain three seats.

The A320 series has three seats on each side, so the applicable distance is a 20 inch wide passage. The referenced paragraph (c)(1)(ii) is also interesting:

  (ii) In lieu of one 10- or 20-inch passageway, there may be two passageways, between seat rows only, that must be at least 6 inches in width and lead to an unobstructed space adjacent to each exit.

This appears to be one layout that Air Canada uses.

There doesn't appear to be any regulation requiring a certain number of lavatories. Aircraft sometimes fly with only one working. Evidently no US agency requires even at least one.

However, the DOT does appear to have a rule created by the Air Carrier Access Act that says:

  New twin-aisle aircraft must have accessible lavatories.

I read that as requiring the aircraft to have at least one, possibly two, lavatories, and that they must be accessible.

  "New aircraft" requirements apply to U.S. airlines with respect to planes ordered after April 5, 1990 or delivered after April 5, 1992. In general they apply to foreign carriers with respect to aircraft ordered after May 13, 2009 or delivered after May 13, 2010.

Of course this wouldn't apply to the A320 series, as it is a single-aisle design. Although some twin-aisle aircraft do operate on shorter routes, they are probably less likely to go the route of ">200 people, no toilets."


What are the chances that you are on plane that has an incident?

I don't know if there is a global compilation. But for Australian operations data exists to allow us to establish a likelihood of being in an incident. Accidents are so rare that it's difficult to get a reliable indicator, however if we are just measuring reported incidents I believe we could get somewhere.

The Australian Transport Safety Bureau (ATSB) has published an "Aviation Occurrence Statistics" report covering 2004-2013.

Let's focus on high-capacity RPT operations, because lets face it, that is probably what most people are interested in.

According to the report, in 2013, there were 597,000 departures of Australian-registered high capacity RPT or charter flights (unfortunately the report doesn't seem to split it into RPT only, possibly because we have a lot of high-capacity charter flights to the mines). In the same year there were 3292 reported incidents to the ATSB and 2 accidents. Therefore I would conclude that if in 2013 you boarded an Australian-registered high-capacity RPT or charter flight, your chances of being in a reported incident were around 0.5%, and chances of being are an accident is 0.06%. The incident percentage is approximately the same for the couple of years prior, so I am confident that this remains around about the mark today - though I would not consider the accident rate to be reliable because there were so few.

The incidents cited in this data vary from loss of separation to a pilot being sick to birdstrikes.

Have a read of the report but before you take it as gospel, keep in mind, as they say, "there are lies, damn lies, and statistics!"


Can lift be created without air downwash?

If no downward acceleration occurs, there can be no lift.

However, a wing of infinite span will use an infinite amount of air for lift production, so an infinitely small amount of downward acceleration already suffices to produce lift.

Clearly, this is a thought experiment that cannot realistically be reproduced in reality.


Why did Airbus skip a few numbers when developing the A380?

The question of aircraft name variants have already been discussed, but I just want to add that other reasons have also been proposed:

The '8' in the 380 resembles the double decker configuration of A380.
It was named A380 because it is twice the size of A340
And of course, it is the lucky number for Chinese.


Can any conclusions about aerodynamic efficiency be drawn on the basis of fly-by noise?

Invariably, aerodynamic efficiency improves with newer designs and so it was from 747-200/300 (not glass cockpit) to 747-400 (winglets + increased span + glass cockpit) to B777 to B787, from A300 to A350. Industry wide pilots were never disappointed by this and proud to be flying the latest lowest drag 'slippery' airplane.
But using noise as an indication of aerodynamic efficiency, could have peculiar factors come into play. The ultra quiet and ultra efficient B787 is so 'clean' or 'slippery' that it requires great anticipation and confidence in technique to fly both the 'speed control' and the CDA Continuous Descent Approach as published at some very major airports.
Many a time, it cannot be flown without the use of speed brakes, the use of which, is (was?) anathema for many pilots.
The  normal expectation is that as long as the speed is above the selected or target speed with speed brakes deployed to aid in reducing the speed, and especially during descent/ the engines would be at flight-idle. Contrary to this, a design feature of the autoflight system pushes the thrust levers up so that they are not at idle but producing thrust when the pilot is doing her best to make the airplane decelerate! So, earlier generation airplanes would have thrust at idle at these points, but the 787 does not.
Even under these circumstances it probably has a smaller noise footprint but an inability to decelerate as per the ATC published speed control targets, could for eg result in gear being lowered earlier than the published preference and this all adds to the sound. The Gear extension point is actually being monitored for variations at such airports.
Despite the above information, theoretically, aerodynamic efficiency could certainly be gauged on the basis of noise provided you were to compare like to like - the comparison would have to be between aircraft similar category, all the airplanes would have to be doing the same maneuver in equivalent configuration eg.

passing 500ft on final approach, max landing weight, landing config with gear down, on speed, and stabilised on approach

OR

level fly by in clean config, height 400ft, 270kts speed.

And there's no accounting for what factors, apart from aerodynamics and engines maybe discovered to be contributing to the noise level.


What is the meaning of these slang terms used in ATC?

Follow the black holes

I have no idea about this one. I looked at the airport diagrams and arrival/departure procedures for MIA, MCO and ORL and I couldn't see anything that seems like it could be confused with the words "black hole". So, I have two guesses:

It's the code name for a set of local taxi instructions
As you suggested, it's the controller's slang for "the twin-engine aircraft in front of you", i.e. the black holes are the exhausts

I think the second possibility is very unlikely, though. A controller at a major international airport - which implies many pilots with English as a second language - is unlikely to use non-standard phrasing for a critical instruction like which aircraft to follow.

Taxi not too deep

This one is a lot clearer from the updated comment you gave: "CLEARED PUSHBACK, NOT TOO DEEP, THERE IS A TRAFFIC PASSING BEHIND YOU". That's exactly what it sounds like: the aircraft was cleared to push back from the gate, but the ground controller was warning the pilot not to push back too far ("too deep") because of another aircraft passing behind.

How is your ride?

This one is ATC asking a pilot for a PIREP. That could be because another aircraft nearby is in turbulence and trying to find a smoother altitude, so the controller asks other aircraft about the ride at their flight levels. Or, since you heard this in the US, it could be for this reason, from the AIM section 7-1-20:

  FAA air traffic facilities are required to solicit PIREPs when the
  following conditions are reported or forecast: ceilings at or below
  5,000 feet; visibility at or below 5 miles (surface or aloft);
  thunderstorms and related phenomena; icing of light degree or greater;
  turbulence of moderate degree or greater; wind shear and reported or
  forecast volcanic ash clouds.

Are there other examples of slang?

I'm sure there are, although slang in general is discouraged because of the potential for misunderstandings. The FAA has a pilot/controller glossary to make sure that everyone is using the same words and phrases as far as possible (ICAO provides one too), but that doesn't mean that people always stick to it 100% of the time. Ex-military pilots - and controllers - in particular sometimes use some military terminology (e.g. bingo fuel) out of habit (presumably) even though they really shouldn't in a civilian setting.


How much does the horizontal stabilizer on a 737 move for one unit of trim?

The stab trim unit is an offset to the actual horizontal tailplane angle. It is added by Boeing to make the trim value positive.

1STU = 1 degree


As at 2020, why don't fighter jets have ≥ 200 rounds for their cannons?

They don't need more rounds.

Modern fighters contain a targeting system that can calculate where the bullets will go, allowing the pilot to fire only when he's sure to hit the target. In some aircraft, the gun is slaved to the targeting system so it can be set to fire automatically when the target crosses the firing line.

In WW2, aiming was more primitive and usually involved firing a long salvo, using the tracer rounds to see where the bullets go and adjusting your aim to hit the target. This required far more rounds for a kill.

The gun is a weapon of last resort, to be used when all primary weapons have been expended. It doesn't make sense to add a large gun magazine when that would reduce the primary payload.

Gun strafing has been superseded by cluster bombs. Since the 2008 treaty forbade their use, small smart munitions have been used instead.


Why isn't luggage that goes in the hold scanned as thoroughly as hand luggage?

The main reason why checked luggage is treated differently is that you cannot access it during the flight, therefore eliminating some of the security concerns (like e.g. a knife in checked baggage is not a risk). When your carry-on bag is hand-searched, it is most likely because something could not be seen properly or looked suspicious on the X-ray.
The checked baggage is still scanned though. The TSA writes:

TSA screens approximately 1.4 million checked bags for explosives and other dangerous items daily. Upon check in, your checked baggage will be provided to TSA for security screening. Once the screening process has completed, your airline will transport your checked baggage on your respective flight as well as deliver it to the baggage claim area. The majority of checked baggage is screened without the need for a physical bag search.
Inspection Notices: TSA may inspect your checked baggage during the screening process. If your property is physically inspected, TSA will place a notice of baggage inspection inside your bag. This is to inform you that an officer conducted an inspection of your property.

Note that the TSA will notify you with a notice in the bag when they opened it. Other countries might handle this differently and just open the bag without telling you.
Some more details of the screening process are given in this article (emphasis mine):

Soon after your suitcase vanishes behind the rubber curtain, it merges with the bags of other passengers -- in large airports, thousands an hour. After traveling up, down and around a vast network of high-speed conveyor belts, it arrives in a cavernous warehouse-like facility. Here, it will be scanned by Transportation Security Administration staff to make sure there's nothing in it that shouldn't be there, primarily explosives, illegal drugs or weapons. If they see any reason to open it, they will. Your bag might also be subjected to other checks, including sniffer dogs, X-ray and laser scanners and machinery designed to detect trace amounts of banned substances. If it passes muster, luggage handlers load your suitcase onto a wagon with the baggage of others on your flight. This wagon is driven onto the tarmac and its contents packed into the hold of the plane.


Is it illegal to fly a Cessna 172S under day VFR with an inoperative vacuum gauge?

Your reading is correct: a Cessna 172 with an inoperative vacuum gauge is not airworthy.
Type Certificate Data Sheet No. 3A12, Revision 85 shows how Cessna 172 models meet FAA airworthiness requirements. Section XII, “Model 172S, Skyhawk SP, 4 PCLM (Normal Category), 2 PCLM (Utility Category), Approved May 1, 1998,” contains

Equipment
The basic required equipment as prescribed in the applicable airworthiness regulations (see Certification Basis) must be installed in the airplane for certification …
NOTE 2: Pilot’s Operating Handbook and FAA Approved Airplane Flight Manual (POH/AFM):  part number 172SPHUS-00 (or later approved revision) is applicable to the Model 172S. The airplane must be operated according to the appropriate POH/AFM …

The Comprehensive Equipment List in Section 6 of the POH/AFM gives the Combination Vacuum Ga[u]ge/Ammeter the R suffix, meaning required.
FAR 91.213(d)(2)(ii) reads

(d) Except for operations conducted in accordance with paragraph (a) or (c) of this section, a person may takeoff an aircraft in operations conducted under this part with inoperative instruments and equipment without an approved Minimum Equipment List provided -
  (2) The inoperative instruments and equipment are not -
    (ii) Indicated as required on the aircraft's equipment list, or on the Kinds of Operations Equipment List for the kind of flight operation being conducted;

But the equipment list does indicate the gauge as required, so this exception does not apply.
To fly the airplane to a repair station to fix the vacuum gauge, apply for a Special Flight Permit (or “Ferry Permit”) with your geographic region’s Flight Standards Office, as provided in FAR 21.197.


Where to find a 1983 NTSB report of a R-22 clutch failure?

I don't think your "death-defying experience" was classified as an incident or accident. Checking the list of occurrences the NTSB classifies as an incident does not show that what happened to you needs to be reported as one. Mechanical failures of all kinds happen on aircraft all the time. Very few of them are required to be reported to the NTSB.


What will happen to the IDG disconnection mechanism if we press and hold it for more than 3 secs?

(A320 training manual)

Pressing the IDG disconnect sends a current to a solenoid. A solenoid is "a cylindrical coil of wire acting as a magnet when carrying electric current."

When activated it pulls a pin that is holding another spring loaded pin that engages the disconnect mechanism.

Holding it for +3 seconds will overheat and thus destroy the solenoid and will require replacement to be able to use it again.

The disconnect mechanism requires a running engine. See here: What happens when disengaging the electricity generators on a B747?

So if it is not running, the next start may also damage the disconnecting mechanism.


What is the highest operational ceiling for an air-breathing jet engine?

Below[1] shows the hypersonic breathing corridor. Without LOX or rocket assistance, the limit is around 140,000 feet (40 km) at around Mach 15.
In 2004 NASA's X-43 achieved a record Mach 9.6 at 109,000 feet (nasa.gov), which if you compare below, is a good match for the aforementioned corridor.

1: Smart, Michael. "Scramjets." The Aeronautical Journal 111.1124 (2007): 605-619. (PDF)


Why is airflow forced to be speed up on the upper surface of an aerofoil?

Airflow isn't compelled to do that by some edict.  It just does it.  "Why" isn't all that meaningful, compared to a theory or formula with predictive power.
Bernoulli says that, under certain conditions, a fluid's speed and pressure have a certain relationship.
How a fluid flows past a obstruction, and what net forces and torques it exerts on that obstruction, aren't because of Bernoulli.
The closest we can come to a reason for the fluid's behavior is the Navier-Stokes equations.  But that's still a model, a simplification.

For an airfoil in conventional steady flight, it's actually more useful to say the reverse:  because the airfoil has been carefully chosen to generate lift under those conditions, the pressure above must be less than that below, so Bernoulli predicts that the flow above must be faster than that below.  And we can confirm that with CFD simulations or with onboard sensors.


Has there even been a case of pilot incapacitation due to food poisoning?

Pilot incapacitation due to food poisoning does appear to have occurred.

The linked question, Is it true that the pilot and co-pilot are required to eat different meals? contains this New York Times article, which describes one incident:

In Australia in 1980, the pilot of a twin-engine commuter airliner suffered from food poisoning and collapsed at the controls. A passenger revived the unconscious pilot, who then was able to land the plane safely.

(However, this may not be quite what you're looking for, as being a single crew plane, it's unlikely he consumed the meal on-board).

The article also describes a number of near misses:

In 1975 luck may have prevented a catastrophe aboard a Japan Air Lines flight  when 143 of the 364 passengers and crew flying from Tokyo to Paris became severely ill just as the plane landed for a fuel stop at Copenhagen. They had eaten omelets that were contaminated with staphylococcal bacteria. The pilots, who had boarded in Anchorage, did not become ill because it was time for their supper, not breakfast. Instead of eating the omeletes, they chose steaks.
In 1982, 10 crew members of an Overseas National Airways DC- 8, including the pilot, co-pilot and flight engineer, became ill about 35 minutes out of Boston on a flight from Lisbon. After the plane landed safely at Logan Airport in Boston, Jo Ryan, a spokesman for the Massachusetts Port Authority, which operates Logan Airport, said, ''The crew all eat different things, but the one thing they had in common was tapioca pudding.''
In 1976 West German health officials reported that two people died and 385 others were sickened by contaminated mayonnaise served aboard a Spantax flight.
In 1976 at least 29 passengers were admitted to a hospital in Australia for treatment of gastro-enteritis after they became sick from a meal served aboard a British Airways flight from Hong Kong to Sydney.

Note the NYT article is dated 1984, so there could have been lots more incidents since then. For example, a search of the Aviation Herald for "food poison"  brings up a number. While you need to read each one and determine if the food poisoning came from the food on board, prior to the flight, or was unconfirmed as the cause, an incident of an inflight meal incapacitating the first officer occurred in a Boeing 737-800 as recently as Nov 18, 2016, flying from Spain to Denmark. In this incident, it is stated that the crew were served different meals.

It says: A chef subsequently informed the first officer that a part of her flight crew meal (cabbage stew) most likely was the source of the food poisoning. Because the cabbage grows in contact with soil, and since it most likely was only heated and not cooked during preparation, live microbiological bacteria might have been present in the hot meal.


Can I fly a paramotor after learning on a paraglider?

It's never safe to teach oneself to fly anything. Aviation pioneers did that out of necessity, but many died or got badly hurt doing it. Training gives you the benefit of decades of hard-won experience without the underpants soiling moments and broken bones.

You are talking about going from being an inexperienced paraglider pilot to a complete novice powered paramotor pilot without the benefit of any mentoring or coaching.

It's a bad idea™


Consequences of stalling while sideslipping in a glider?

Yes if you were to stall the airplane while in a side slip it will probably depart, or start to depart, into a spin.  How aggressively would depend on the glider's actual stall behavior, some being more benign than others, but say you were in a glider with an abrupt stall with minimal warning and a sharp nose drop.  That sort of glider would spin if you didn't initiate recovery right away.

This isn't such a big problem, because the nice thing about gliders is you don't have power to confuse things when it comes to pitch attitude vs speed.  For a given configuration (weight/CG etc), if attitude X gives speed Y than you can be certain that any time you pitch to attitude to X you will get speed Y, with or without an airspeed indicator.

So, if you are on final at 50 kt, and want to side slip, just make sure you lower the nose a couple of degrees during the slip and control the pitch attitude, so that you will maintain somewhere around 50kt with the additional drag and there is very little risk of stalling and spinning. Easy peasy.

You also have the other impending stall cues, like softening controls, noise dying off, and such, so if you are aware and on top of things there shouldn't be a problem and it would take some ham fisted flying to really mess up.

If you are getting trained well, there should be dedicated no-airspeed instruction and practice and once you are considered a proficient pilot you should have no problem with flying safely with no airspeed for all maneuvers (if you sent me out in a power plane on some kind of wacky challenge, and told me I could only have one operating flight instrument, my choice would be a compass).


Your instinct is correct; almost all of the key airspeeds — those at which something special happens aerodynamically — vary with weight.

There's a distinction, though, between "speeds at which something special happens aerodynamically" and "regulatory limiting speeds that prevent you from doing something bad."

For example, VNE is a regulatory value; it is prohibited to exceed this speed at any weight. This value includes a safety margin and is determined from flight test data. Nothing special happens aerodynamically at the published VNE speed. (Thank goodness!) The special stuff, like aeroelastic flutter or structural failure, happens at some speed well above VNE, regardless of your weight (as long as it's within the allowable CG envelope of course).

Another example, VFE, is similar. Nothing special happens at this speed. It's just a safety value: as long as you're below this speed, you won't tear the flaps off the plane if you extend them, regardless of your weight.

Almost all speeds that aren't "regulatory limits" do indeed change with weight. Some examples:

VA design maneuvering speed
VX best angle of climb speed
VY best rate of climb speed
VR rotation speed
VS0 landing configuration stall speed
VS1 "specific" configuration stall speed

For larger multi-engine airplanes that you'll encounter later in your flying career:

V1 engine failure recognition speed (or takeoff decision speed)
V2 takeoff safety speed
VMC minimum control speed

(Note that a lot more factors besides just weight can go into these latter speeds, such as atmospheric conditions and reduced-thrust takeoffs.)

For small airplanes, it is common to publish these speeds as single values, measured at gross weight. For many of them there are also graphs in the performance section that show you how the actual speed varies with weight.

For larger aircraft, the performance graphs (or calculations) are always used. For example, you won't use a single "stall speed" value from a handy table in the "POH" of a 747. In these types of aircraft, key numbers are calculated as needed on each flight for current weight.


Can an automatic vane-based stabilizer really work?

Yes, this vane-based stabilizer really did work. In fact the pendulum system for direction control also worked as it was used to sense yaw in a slip, just like the ball in a turn and bank indicator.
The entire system worked so well that Orville Wright received the 1913 Collier Trophy "For development of the automatic stabilizer" after demonstrating it for the judges.
The Wright Bros work in automatically controlled flight was overshadowed the following year when Elmer A. Sperry won the 1913 Collier Trophy "For gyroscopic control".
WRIGHTS DEVELOP AUTOMATIC STABILIZER

In the fall of 1913, Orville installed the stabilizer on a special Wright Model E airplane that utilized a single pusher propeller. He kept the details of the stabilizer secret even from the Wright Company. He purposely waited until the last day of the year to fly for the prize.
He invited the Aero Club’s judges to Huffman Prairie to see a demonstration of his new device on a cold snowy day, December 31st.
He turned up his coat collar, put on a pair of goggles and took off. He made a total of 17 flights.
His most spectacular flight consisted of 7 full circles of the field with both hands held in the air. The automatic stabilizer kept the same angle of bank and almost the same altitude. He wowed the judges and was awarded the prize on February 5, 1914.
The stabilizer was then offered as an option for use with the sale of Wright 1910-1911 Model B flyers.
However, it saw little use, because on June 18, 1914, a young Lawrence Sperry, as part of a great safety competition, unveiled a totally new type of stabilizer to the world. The safety competition was jointly sponsored by the Aero-Club de France and the French War Department.
In his demonstration flight, Sperry took off from the Seine in a Curtiss C-2, climbed to altitude and flew back down the river. At the appropriate moment, his mechanic, Emile Cachin, crawled 7 feet out on the wing as Sperry lifted his hands from the controls and stood up in the cockpit. The plane sped by the judges as the crowd went wild.
What Sperry had done was adapt a balancing mechanism invented by his father, Elmer, for counteracting the rolling of ships, to an airplane. The device employed two gyroscopes that performed the function of the pendulum and vanes in the Wrights’ device.


What changes are needed for a piston-prop aircraft to withstand saltwater environment?

There is no way to fully protect an aircraft from the effects of salt water corrosion, even when any aluminium is treated with protection products like Alodyne. In fact, there is no way to prevent corrosion from happening anywhere unless you protect the item in question. Corrosion can affect an aircraft even in the dry climates.

Even if it is not landing or taking off in salt water, just being close to a body of salt water will cause corrosion. All you can do is be very proactive in washing the aircraft with clean water after every day, and using products like Corrosion-X to coat surfaces with a corrosion protection film. Even WD-40 will do a great job of this, because it is not a lubricant, it is designed as a hydrophobic [W]ater [D]isplacement product. You need to protect both exterior and interior areas, even inside the wings. Just ask any mech who has worked on aircraft for any length of time at a location near salt water.

Tailhooks and wing folding do nothing about corrosion, it just helps get the aircraft on the carrier and allows for efficient use of the deck areas.


Can a company return an aircraft in leasing?

Yes there is a penalty to pay if you break the lease contract by returning it before the completion date. Same as a car.  It may be that they simply continue the lease payments to the end of the contract, or the contract may have some kind not-quite-so-bad penalty that was negotiated to sweeten the deal for the airline to get the deal in the first place.

The airline will do a business case and balance the penalty costs of breaking the lease early against the losses of continuing to run their unwanted behemoth to the end of the lease contract and proceed based on the cheaper option.  Even if they have to keep making lease payments to the end of the contract, it still may be worthwhile to return the aircraft and escape from maintenance and insurance costs, if the aircraft was killing them financially, which is what this sort of thing suggests.


Where can I find numeric maps of aerodromes?

Airport Diagrams such as this one of KPNE

are published here on the FAA website as well as in in the airport facilities directory. These are up to date and considered legal for navigation as far as I know. If you are looking for them in another type of format that may be tough, you can try reaching out to the specific airports or the FAA directly.


What is the meaning of the percentage used to describe the thinness of this glider's airfoil?

14.5% given in the article is the (maximum) thickness to chord ratio, expressed in percentage. It is usually used to explain how thin (or thick) the airfoil is. Note that this is a characteristic of the airfoil.
From the NASA page Wing geometry definitions:

Airfoil thickness to chord ratio, image from NASA page Wing geometry definitions

... The straight line drawn from the leading to trailing edges of the airfoil is called the chord line. ... The maximum distance between the two lines is called the camber, which is a measure of the curvature of the airfoil (high camber means high curvature).
The maximum distance between the upper and lower surfaces is called the thickness. Often you will see these values divided by the chord length to produce a non-dimensional or "percent" type of number.


What do the callouts "approaching minimums" and "minimums " mean?

The "Approaching Minimums" callout is made by the Pilot Monitoring (or, in some cases equipment, the GPWS -- Ground Proximity Warning System) as the aircraft is descending on an instrument approach and has reached an altitude 100 feet above the minimums for that approach -- the Decision Altitude (DA -- typically used for a Cat I ILS, and set as XXX' MSL) or Decision Height (DH -- typically used for a Cat II or Cat III ILS and set as XXX' or XX' on the Radio Altimeter) or Minimum Descent Altitude (MDA -- typically used for a nonprecision approach and set as XXX' MSL).  The response by the Pilot Flying is usually standardized and indicates he is looking outside in order to acquire the visual references he'll need to land.

The "Minimums" callout is made at the minimum altitude, and this is the point that the Pilot Flying has to make a decision -- continue or go around.  His response at this point is again standardized so that the other pilot is entirely clear on the course of action.  His response is usually something like "Landing" or "Continue", or else "Go Around."  Often, the autopilot comes off at this point as well & you hear the horn indicating such on the CVR as well.


How do pattern and overflight altitudes work for airports underneath Class C airspace?

Just talk to the controllers. We live under a Class B with several underlying Class C or D fields. They'll talk to you. They'd rather know what you're planning to do than not, keeps everyone safer.


Can an aircraft operator hire a Commercial Pilot to fly their aircraft under part 91?

To answer my own question. As pointed out by @MichaelHall and @pericynthion Tom would not fall under "Commercial operator".

Here is the definition for reference:

  Commercial operator means a person who, for compensation or hire,
  engages in the carriage by aircraft in air commerce of persons or
  property, other than as an air carrier or foreign air carrier or under
  the authority of Part 375 of this title. Where it is doubtful that an
  operation is for “compensation or hire”, the test applied is whether
  the carriage by air is merely incidental to the person's other
  business or is, in itself, a major enterprise for profit.

Another term which comes in useful here is:

  Operational control, with respect to a flight, means the exercise of
  authority over initiating, conducting or terminating a flight.

In this case, Joe would have operational control since it is his aircraft. Since Commercial Operation means "...person who... engages in the carriage by aircraft...", then Joe is the "person" and not the pilot Joe.

Another term within the definition is "air commerce". This means:

  Air commerce means interstate, overseas, or foreign air commerce or
  the transportation of mail by aircraft or any operation or navigation
  of aircraft within the limits of any Federal airway or any operation
  or navigation of aircraft which directly affects, or which may
  endanger safety in, interstate, overseas, or foreign air commerce.

Commerce is the activity of buying or selling. If we look at it from that level, the operator (Joe) is not engaging in air Commerce, because when you are operating an aircraft, you're perfectly allowed to pay for the usage of your own plane. So if this is not air commerce, then it falls under Part 91, and Tom is good to go.

However, if Joe were to engage in air commerce such as shipping stuff, but still hire Joe, then this falls under part 119 then 135 operations.

Refer to this legal interpretation: https://www.faa.gov/about/office_org/headquarters_offices/agc/practice_areas/regulations/interpretations/data/interps/1993/green%20-%20(1993)%20legal%20interpretation.pdf

Based off this interpretation, the aircraft and operator must be separate from the pilot. Also, the operator cannot conduct air commerce flights.


Can a jet stream make a subsonic plane fly at a supersonic speed relative to the ground?

Yes, the ground speed of a subsonic aircraft could be larger than the speed of sound. As an example, during the record time for a subsonic Atlantic crossing a Boeing 747 reached speeds of up to 1327 km/h:

Experts are hailing a British Airways flight as the fastest subsonic New York to London journey.
The Boeing 747-436 reached speeds of 825 mph (1,327 km/h) as it rode a jet stream accelerated by Storm Ciara.

(BBC)
The speed of sound at sea level is usually around 1235 km/h. The speed of sound is however temperature dependent and will be lower at high altitudes, therefore the ground speed in this case was higher than the speed of sound, regardless of the altitude.
This does not make the aircraft supersonic. A supersonic flight implies that the TAS (True AirSpeed) is higher than the local speed of sound. This was never the case for this 747 flight.

If it can, does the plane create a sonic boom on the ground?

No, a sonic boom can only be created locally by an aircraft flying faster than the local speed of sound. It is unrelated to the ground speed.
Consider the following illustration of a sonic boom:

(image source: Wikipedia)
You can see a line of sound waves currently hitting the person standing on the ground. This is the sonic boom you would hear.
I modified this image for subsonic flight:

You can see that the circles never intersect and can therefore never form a line of sound waves. If the aircraft is in a tailwind, the sound waves would be emitted in the same way, they would just move faster across the ground as a whole, but there is no relative difference between them (and the aircraft). Therefore, there is still no sonic boom even when the aircraft's ground speed is faster then the speed of sound.
Note however that the wind speed would change with altitude. The jet stream does not extend all the way to the ground. This would distort the circles when they get closer to the ground, but it cannot create a sonic boom.


Can jet airplanes operate on 'rough' airfields?

The main problem with most jet airliners is that the engines are placed close to the ground. If the field is not paved, this increases the risk of damage to the engines from ingesting FOD (foreign object debris).

There are, however, jets that can operate from un-paved fields.

The 737-200 has an option called a "gravel kit." Despite having engines close to the ground, this kit helps to prevent the engine from sucking in FOD, which allows the aircraft to operate off of gravel runways. It also includes an addition to the nose gear to help prevent gravel from getting kicked up. For this reason, airlines like Canadian North still operate multiple 737-200 aircraft in order to provide service to airports with gravel runways.

High-wing aircraft are better suited for this type of mission (see What are the pros and cons of high-wing compared to low-wing design?). The C-17 is a military airlift designed to operate from remote airfields. Its wings are placed above the fuselage rather than below, which allows the engines to be mounted further above the ground. The IL-76 is a Russian aircraft of a similar configuration that also operates out of unpaved fields.

Aircraft with engines mounted on the rear fuselage also protect the engines from ingesting FOD. The new Pilatus PC-24 jet advertises the ability to operate from unpaved strips. Older aircraft like the 727 or the Tu-154 have this engine placement as well, and both can operate from unpaved fields.

737-200 landing on a gravel runway. The gravel kit is visible as the small extension just below the front of the engine, and the addition to the rear of the nose gear.


How can shifting to TCP/IP make current aviation systems more delay-tolerant?

The current air/ground systems (based on OSI) are aviation unique. And they are limited by design to "messages no larger than 3.5 kilobytes". This limits how much information can be sent to/from an airplane, and is a major roadblock towards time based navigation and the broader data-hungry Global Air Navigation Plan (GANP), which includes SWIM for example.

SWIM: an advanced technology program designed to facilitate greater sharing of Air Traffic Management (ATM) system information, such as airport operational status, weather information, flight data, status of special use airspace, and National Airspace System (NAS) restrictions.

Option one, develop better aviation-unique systems (OSI) that can handle more data. Very expensive to certify, very hard to get everyone to agree on the system. Option two, use the IPS (Internet Protocol Suite) that has proven itself. And thus commercial off-the-shelf equipment can be used.

The reasoning at the time was that the OSI protocols were more formally specified and included such things as detailed protocol implementation conformance matrices and combinations of functions at each protocol level called profiles, and thus were more suitable for avionics certification.
(...)
However, as is common knowledge, the TCP/IP protocols have long since been proven in the World Wide Web and therefore are able to offer potential economic benefit and provide for the rapid introduction of new services in the global aviation environment.

OSI means OSI-based (such as ARINC 429), and is unique to aviation. Example: A router on a Boeing 777 is not sold on the non-aviation market. What they want to do is use off-the-shelf solutions to be used on airplanes. Using ready-made solutions is more economical than creating solutions for a specific industry. The current solutions can't handle the data requirements of the future.

IPS will also allow easier integration with the already IPS based ground/ground communication between airlines and air traffic management. The current plan is to have a seamless transition from OSI to OSI+IPS to IPS in the next 15 years or so.
Why is IPS more delay-tolerant?
Example: When every single user (pilot, airline, ATC, airport, etc.) has access to the same real-time weather data (e.g. via SWIM), decisions can be made more correctly, in a timely manner, and consistently across the users. Just like what FANS-1 did for the Pacific operations in the 90's, but way bigger (history below).
This is the gist of it and explains why the shift. For technical standards there are plenty of ICAO documents on the web: ICAO Doc 9705 (OSI) and ICAO Doc 9896 (IPS).
Also related: Why Boeing and Airbus are Pushing for IPS (aviationtoday.com)

A brief history of aviation data comms:

ACARS started as a punch clock for the flight crews by auto reporting the different flight phases (aka OOOI)
Then Europe expanded on what the US has done with it and used it for operational control, e.g., by keeping track of where the fleets are, etc. (ops driven)
Then British Airways took it a step further for airplane health monitoring (engineering driven)
Then the Pacific region wanted to benefit from it, and so came Boeing's FANS-1, enabling flights that took off with +11 hours old weather forecasts to readjust their routes mid-flight. The flights can now receive from the airlines the weather updates, new flex-routes, etc., and communicate it to the ATC. Shaving off 15+ minutes on long transpacific flights, and enabling more payload (2+ tonnes per flight)
Now FANS serves ATC (CPDLC and ADS-C) in oceanic airspace, and operators (AOC)
Airbus also made its own FANS-A, now they are known as FANS-1/A
Then they became FANS-1/A+ by adding a latency timer for the ATC messages (CPDLC), so a plane would not receive a delayed message that was meant for a previous flight this plane flew
Then PM-CPDLC (aka LINK2000+ and ATN-B1) came along in Europe, which requires yet again different equipment.

For ATC, FANS-1/A+ is mainly used in oceanic airspace and in delivery clearances in the US, and CPDLC (ATN-B1) in parts of the European airspace, and the hardware for both is not compatible (if used together) on older planes.
FANS-1/A+ combined with ATN-B1 creates FANS-2/B as one package (like on the Boeing 787). The plan is to make all systems use a standard network with higher bandwidth, which is the current goal of FANS-3/C (FANS-1/A+ and ATN-B2) using an IPS infrastructure while supporting the legacy planes. Check the progression of the 3 stars I added below.
(ICAO)

Note: the acronyms above may seem to overlap, e.g., for ACARS and CPDLC, but as the uses expanded and new systems were added, the meaning now depends on the context. For example the early FANS-1 CPDLC is still ACARS at its core, and also CPDLC can refer to ATN-B1 in Europe, or DCL-CPDLC (DCL = Delivery Clearance) in the US for example. It's an alphabet soup.

Further reading:

All You Need to Know About CPDLC ATN-B1
What you should know about FANS-1/A+ ATN-B2


What is the purpose of a freewheeling unit in an helicopter, if a centrifugal clutch is already present?

the centrifugal clutch will only disengage after its rotating speed falls to the disengagement point. The over-running clutch disengages the engine from the rotor at the very instant that the engine's rpm falls below that of the rotor.

In this way, the rotor is never wasting kinetic energy by trying to turn over a dead engine and the vehicle stands a better chance of achieving successful autorotation.


Flight control mass balance weights are used primarily to prevent things like flutter. Most airline manufacturers are able to perform analysis of their designs to determine the exact weight to introduce, and where to place it. The rest use static balancing. This article from the Experimental Aircraft Association is not an airliner example, but it provides a good explanation of the why and how of flight control balancing.


Do high-speed ailerons help with the roll rate control in non-FBW?

No it does not reduce the aeroforces: the hydraulic actuators that deflect the inboard aileron have as much of a force to apply as the ones at the outboard aileron. Force for deflecting a flight control surface is a function of dynamic pressure, surface area and of surface deflection.

As you state in the question, the inboard aileron reduces wing twist which could produce aileron reversal at high dynamic pressures, particularly problematic with relatively thin wings and high wing sweep angle.

The reduced moment arm affects the aircraft response upon aileron deflection. The problem with the ailerons is that a deflection equates to an end roll rate, as opposed to the elevator and rudder where a deflection results in an end angle. Many aircraft have a slow roll oscillation in cruise that the autopilot compensates for. If it must do that with an outboard aileron at M=0.85, the strong response of the outboard aileron makes it hard to not overcompensate. I have seen the inboard ailerons on a B747 do a slow deflection dance in cruise, while the aircraft roll angle stays perfectly still.

Slow roll oscillation in cruise was a problem with the F100 for a short while, the gains in the autopilot could not be set low enough to obtain a constant zero attitude. Not really a problem, only in the perception of passengers looking out of the window. It was ultimately solved using different logic but unfortunately I don't know how they did it.


Is it possible to bluff one's way to the flightdeck like in Catch Me If You Can?

A lot has changed since the Frank Abagnale / "Catch Me If You Can" days, and riding as a non-revenue passenger (particularly in the cockpit jump seat) is no longer not as simple as grabbing a passable captain's uniform, polishing your shoes up, and smooth-talking the flight crew.

Someone seeking a ride in an airplane jump seat would still have to pass through airport security and prove their identity & authorization to occupy such a seat to the satisfaction of the crew operating the flight, which would likely include checking credentials that are at lease somewhat difficult to forge.

So in short it's possible – if someone is particularly adept at social engineering, forgery, and has at least a working knowledge of airport & airline security procedures they might get away with it – but it's extremely unlikely, and as has been pointed out the consequences if and when you get caught are particularly unpleasant these days.


What is the difference between centre of pressure, aerodynamic centre and neutral point?

Any body moving in a fluid experiences pressure forces over its surface. The concepts of center of pressure, aerodynamics center and neutral point are useful in understanding the effects of these forces. Let's take an airfoil moving in air with subsonic flow attached to the body.

Center of Pressure The center of pressure is the point where the total sum of a pressure field acts on a body. In aerospace, this is the point on the airfoil (or wing) where the resultant vector (of lift and drag) acts.

Source: avstop.com

As the airfoil angle of attack changes, the pressure field changes. Due to this, the center of pressure changes with variation in the angle of attack. In the airplane's normal range of flight attitudes, if the angle of attack is increased, the center of pressure moves forward; and if decreased, it moves rearward.

Source: www.flightlearnings.com

As the center of gravity (the point where the weight of the body acts) is fixed, this movement of center of pressure affects the  stability of the aircraft.

Aerodynamic Center The resultant (or the pressure forces) also cause a moment on the airfoil. As the angle of attack increases, the pitching moment at a point (for example, the center of gravity) also changes. However, the pitching moment remains constant at a particular point, which is called the aerodynamic center.

Source: www.theairlinepilots.com

For symmetric airfoils in subsonic flight the aerodynamic center is located approximately 25% of the chord from the leading edge of the airfoil. This point is described as the quarter-chord point.

Thus the aerodynamic center does not change with variation in angle of attack. Due to this, the aerodynamic center, rather than the center of pressure is used in the analysis of longitudinal stability.

Neutral Point Consider the whole aircraft. The lift of the wing acting through the center of pressure is in front of the center of gravity of the aircraft. This causes a destabilizing motion (increase in lift to increase in angle of attack causes a nose up moment, further increasing angle of attack). This is counteracted by the moment produced by the lift of the horizontal stabilizer (which is a small wing), acting behind the center of gravity.

"AirStability" by User_A1 - SVG derivative of Public Domain work by G J Vigurs. Licensed under GFDL via Commons.

As the center of gravity is moved forward, the stability of the aircraft increases (as the main wing lift arm is reduced) and the aircraft is statically stable.

Source: quest.arc.nasa.gov

As the center of gravity is moved aft, the main wing lift moment arm increases and the aircraft stability decreases. The aircraft is said to be statically unstable.

Source: quest.arc.nasa.gov

As the aircraft is stable when center of gravity is in the nose and unstable when center of gravity is in the tail, there is a position in the middle where the aircraft is neither stable nor unstable i.e the stability is neutral. This point is called the neutral point. The neutral point is fixed for a particular aerodynamic configuration of the aircraft.

Source: quest.arc.nasa.gov

Thus,

Center of pressure of an aircraft is the point where the Lift acts.
Aerodynamic center is the point in the wing where the pitching moments are constant.
The neutral point is where the center of gravity of the aircraft is neutrally stable


Do airlines schedule departures based on average environmental conditions of departing airport?

In general, high temperatures affect the performance of the aircraft in two major ways:

As the density is lower at higher temperature, the thrust produced by the engine is reduced.
The lift produced is reduced as lift is proportional to the density.

Due to these reasons, an aircraft operating in hot condition will have to either reduce weight for taking of from a fixed runway length or increase the takeoff run for taking off with the same weight. Also the climb performance will be affected at high temperatures.

Due to this, the airlines could've schedule operations in conditions when the temperature is less if they believe that takeoff weight is critical for example, in long range fights or where a set number of passengers is necessary for economical operation.

However, this problem is mostly critical in case of 'hot and high' airports. In this case, this is most probably for facilitating the arrival of passengers in destinations in the morning.

For example, the SWISS 296 leaves Dar Es Salaam at 11:20 PM (its connecting flight lands only at 1005 PM) and reaches Zurich at 06:16 CET.


Can regular emergency exits not work after crashlanding?

All regular exits are generally used in an emergency. This information would be included on the safety card and in the briefing by the crew before the flight.

Of course, during a crash, structure can deform and exits can become blocked. Regulations require evacuation within time limits using only half of the available exits. This must be demonstrated to be possible.

Here is a Q400 safety card, showing that two forward and two aft exits are used for evacuation. The forward right exit (called R1) is an emergency exit.

Source


Are there any special considerations involved in designing manual flight controls for supersonic/hypersonic aircraft?

In the transonic region, control forces may become too high for manual control (e.g. controls froze in WW2 planes diving at high speeds), so supersonic aircraft usually have powered controls rather than manual, cable-operated controls.

You also get CoG shift you have to compensate for. This is often done via a Mach trim system or by automatic fuel transfer.


Why do airlines outsource regional flying?

This article breaks it down super nicely, and has most of the info you are looking for. The key quote from my reading of it is

  The simple answer is that using regional airlines saves major airlines
  money compared to them operating a flight themselves. Where do the
  cost savings come from? For one, employees are paid significantly
  less.

There are also some serious union and historical reasons for the setup, regional airlines code sharing with majors is in some regards a way to skirt around union negotiations

  The first reason is that it would likely eliminate the cost advantage.
  Most major carriers have negotiated with their unions that flights
  with fewer than “X” number of seats will be operated by regional
  airlines. You can bet that if the regional airlines became part of the
  major airline (even if a separate division), the major carriers’
  unions would be fighting for significantly better pay for those crews.

  ...

  Historically another reason the major carriers have contracted out to
  regional carriers is because it allows them to share some risk. Keep
  in mind that historically airlines are ridiculously unprofitable
  (though that has changed recently). So leased planes were almost a
  liability rather than an asset, given that they were losing money with
  just about each flight.

Here is another interesting paper on the subject and good info here.


How are fuel injectors in a jet engine monitored to detect malfunction?

Fuel nozzles are overhauled and bench tested to meet the manufacture's operational limits.  They are controlled for both flow (back pressure) and also flow pattern.  The FADAC monitors fuel flow, this along with the compressor vane position are the main input controls for thrust generation.

The fuel nozzles do degrade during engine's operation.  This contributes to the engine running hotter as it ages.  Other contributors are the erosion of the compressor hardware and the burning/oxidation of the combustion chamber and turbine hardware.  In fact a defective fuel nozzles may lead to a "hot spot" that accelerates the burning/oxidation of the combustion chamber.  The FADAC and flight crew will monitor the throttle response and also the Exhaust Gas Temperature (EGT) as the controls to understand the relative health of the fuel nozzles.  If the engine exceeds the EGT limit a mandatory boroscope inspection is required to keep the Aircraft in service, this inspection will visually verify the condition of the fuel nozzles and combustion chamber.


Load factor and how does velocity affect it?

b) means straight up into a vertical loop with a 300m radius, with the load factor calculated at the 9 o'clock position as velocity is decreasing and G increasing on the up side, 12 o'clock position as velocity and G reach a minimum at the top inverted,  and 3 o'clock position as velocity and G is increasing on the down side, all due to gravity alone.  Bank angle is not a factor and can be considered "level" flight from that perspective.

a) means the load factor in a 300 m radius level turn, at whatever bank angle is required to achieve that radius at a constant 130 m/s.

The question should end with "loop and turn" instead of just loop and I would assume the 90, 180, 270 business also applies to the equivalent locations in the level turn in the case of a) (and I would presume to be the same number at each location in the level turn).

The question is pretty poorly done, but that's how I would interpret it to make do with what is presented.  Between the confusion over loop and turn and the typos like "id" for "is", the exam writer needs some remedial training.  So if you get the answer wrong, and it's important, I would protest it if that is feasible.


Can a non-citizen get a pilot job in Canada if they have an FAA CPL?

It would be like taking any other job in Canada.  If you aren't a permanent resident/landed immigrant, you need to obtain a temporary work visa with job offer in hand.

In Canada you can hire on with a 2nd tier (Regional) carrier with lower hours than the US because there isn't the "Colgan Rule" that requires 1500 hours (US Regionals have complained bitterly about this, because there are situations where they are forced to take inferior candidates because he/she has the hours, and pass on a superstar that is 500 hours short).

The candidate market is becoming very tight.  Air Canada Jazz operates Q400s and CRJs and is taking pick of the litter kids right out of the colleges and puts them through a more comprehensive training program than the normal two-weeks-then-7-sim-sessions-and-a-checkride whirlwind type course, although off the street candidates will need more time.  West Jet Encore runs Q400s and has dropped their 1500 hour off the street requirement for new FOs down to 1000 hrs and is also running a special mentoring program with the colleges.