The last section of the final approach is sometimes referred to as short final. Departure leg, Initial, or Climb out. The climbing flight path along the extended runway centerline which begins at takeoff and continues to at least 1/2 mile beyond the runway's departure end and not less than 300 feet below the traffic pattern altitude. The names of the legs are logical and based on the relative wind as seen looking down a runway facing into the wind. An aircraft flying upwind heads into the wind, flying crosswind heads across the wind, flying downwind heads in the direction of the wind just like blown smoke. While many airfields operate a completely standard pattern, in other cases it will be modified according to need. For example, military airfields often dispense with the crosswind and base legs, but rather fly these as circular arcs directly joining the upwind and downwind sections. Procedures in the pattern Aircraft are expected to join and leave the pattern, following the pattern already in use. Sometimes this will be at the discretion of the pilot, while at other times the pilot will be directed by air traffic control. There are conventions for joining the pattern, used in different jurisdictions. In the United States, aircraft usually join the pattern at a 45° angle to the downwind leg and abeam midfield. Although aircraft may legally join the pattern at any point, the AIM and AC 90-66B strongly recommend using a 45° entry at pattern altitude. In Canada, aircraft at uncontrolled airports usually cross the airport at midfield at pattern altitude from the upwind side, turning onto the downwind leg. Although joining straight in downwind is also a possibility. At controlled airports, the tower typically directs aircraft to join the downwind leg, base leg, or straight into the final leg. In the UK, South Africa, and New Zealand a standard overhead join is recommended. In Europe, aircraft usually join the pattern at a 45° angle to the downwind leg, in the beginning of the downwind leg. Fast aircraft, for example military jets, may enter the pattern with a run-and-break (in the US, overhead maneuver or overhead break). The aircraft flies at speed along the final leg, and makes a sharp, high-G turn above midfield to lose speed and arrive on the downwind leg at pattern altitude and in landing configuration. Similarly, there are conventions for departing the pattern. In