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| CHAPTER 7. Takeoff and Departure Climbs
Takeoff Roll As the aircraft is aligned with the takeoff path, takeoff power is applied smoothly and rapidly. As the aircraft accelerates, the control bar is moved full forward to the front tube to establish a positive angle of attack and to reduce the weight supported by the nosewheel because any lift on the wing takes load off of the landing gear. When the aircraft is held at a nose-high attitude throughout the takeoff run and as speed increases and lift develops, the wings progressively relieve the wheels of more and more of the WSC’s weight, thereby minimizing the drag caused by surface irregularities or adhesion. If this attitude is accurately maintained, the aircraft virtually fl ies itself off the ground, becoming airborne at airspeed slower than a safe climb speed because of ground effect. [Figure 7-14]
Lift-Off and Initial Climb After becoming airborne, the nose should be lowered very gently with the wheels clear but just above the surface to allow the aircraft to utilize ground effect to accelerate to VY, or VX if obstacles must be cleared. Extreme care must be exercised immediately after the aircraft becomes airborne and while it accelerates to avoid settling back onto the surface. An attempt to climb prematurely or too steeply may cause the aircraft to settle back to the surface as a result of losing the benefi t of ground effect. An attempt to climb out of ground effect before suffi cient climb airspeed is attained may result in aircraft incapacity to continue climbing as the ground effect area is traveled, even with full power for lower powered WSC aircraft. Therefore, it is essential that the aircraft remain in ground effect until at least VX is reached. This requires a feel for the WSC aircraft and a very fi ne control touch in order to avoid overcontrolling the pitch control as required control pressures change with aircraft acceleration. Simply getting off the ground as quickly as possible and fl ying in ground effect is the goal. In addition to normal takeoffs, additional common errors in the performance of soft/rough fi eld takeoffs are:
Rejected Takeoff/Engine Failure Emergency or abnormal situations can occur during a takeoff that requires a pilot to reject the takeoff while still on the runway. Circumstances such as a malfunctioning powerplant, items dislodging during takeoff, inadequate acceleration, runway incursion, or air traffi c confl ict may be reasons for a rejected takeoff. Prior to takeoff, the pilot should have in mind a point along the runway at which the aircraft should be airborne. If that point is reached and the WSC aircraft is not airborne, immediate action should be taken to discontinue the takeoff. Properly planned and executed, chances are excellent the aircraft can be stopped on the remaining runway without using extraordinary measures, such as excessive braking that may result in loss of directional control, damage, and/or personal injury. In the event a takeoff is rejected, the power should be reduced to idle or the engine shut off and maximum braking applied while maintaining directional control. If it is necessary to shut down the engine due to a fi re, the fuel supply should be shut off and the magnetos turned off. In all cases, the manufacturer’s emergency procedure should be followed. What characterizes all power loss or engine failure occurrences after lift-off is urgency. In most instances, the pilot has only a few seconds after an engine failure to decide what course of action to take and to execute it. Unless prepared in advance to make the proper decision, there is an excellent chance the pilot will make a poor decision, or make no decision at all and allow events to rule. In the event of an engine failure on initial climb-out, the pilot’s fi rst responsibility is to maintain aircraft control. At a climb pitch attitude without power, the WSC is at or near a stalling angle of attack. It is essential the pilot immediately lower the pitch attitude by pulling the control bar back to the chest immediately to prevent a stall. As discussed earlier in the climb section, a preventative measure is to climb to a safe altitude, 200 feet was used as an example, at least the minimum safe climb speed as recommended by the manufacturer to lower pitch angle as a safety measure for this situation to minimize a high pitch angle close to the ground. The pilot should establish a controlled glide toward a plausible landing area (preferably straight ahead on the remaining runway). |
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