POINTS for PILOTS

Northland Age, Volume XVI, Issue 78, 25 July 1947, Page 4

POINTS for PILOTS

by “Prop” Before attempting more advanced manoeuvres, it is necessary for the pilot to have -a thorough grounding in medium turns and ability to execute them efficiently from straight and level flight, climbing and gliding. A medium turn is one which does not require more than 30 degrees of bank and can be induced by very slight movements of the controls of the Tiger Moth; it is therefore necessary to practise extreme lightness of touch to avoid the common fault of over-controlling. With the engine revs, at normal cruising and the aircraft trimmed correctly for straight and level flight, the turn is comparatively easy providing the following points are given attention in addition to the general practice of smooth controiling. 1. Slight movement of the rudder when initiating the turn and slightly coarser movement when recovering. 2. —Keep the angle of bank con- : # stant with the ailerons. (It is necessary to “hold-off” bank when the desired angle has been reached). 3. Maintain a gentle backward pressure on the stick throughout the turn to keep the nose in the correct position relative to the horizon and to maintain a constant air speed, remembering to release the pressure* during the recovery. 4. —Use the rudder sparingly when in the turn and then only to correct slipping if the angle of bank is as lequired. 5. —Check airspeed, altitude and the turn and sideslip indicator occasionally, but fly by the position of the nose relative to the horizon. Assuming that climbing turns arc to be carried out when the aircraft is trimmed for a straight climb, the procedure is the same as that for level turns with the following exceptions : 1. —As the aircraft is flying at a reduced airspeed (e.g. Tiger Moth 65 m.p.h.) and as the turn imposes a greater loading, the safety margin must be maintained by increasing either the airspeed or the engine revolutions. In the case of the Tiger Moth, it is recommended that the<airspeed be maintained at a constant 65 m.p.h. and the engine revolutions increased from the normal climbing figures of 1950 or 2000 r.p.m. The throttle is advanced as the turn is commenced—not before, so that the airspeed will remain constant with little effort on the part of the pilot. Naturally, when the turn is completed it is necessary to throttle back to normal climbing revs, and to check the airspeed. 2. —lt is not necessary to make a conscious point of holding off bank especially in the Tiger Moth, as the reduceJ airspeed and the peculiar design ot the ailerons compensate to some extent for the tendency to roll further into a steeper turn. Gliding and descending turns (i.e., turns which are carried out when the throttle is closed, or partly closed and the aircraft descending, correctly trimmed and at the appropriate speeds) are similar in execution to level turns and climbing turns. They are carried out at 70 m.p.h. in the Tiger Moth ; this increase from 65 or 60-65 m.p.h. is necessary for the same reasons as given for the increased engine revs, in climbing turns. The nose must therefore be allowed to drop slightly as bank and rudder are applied in the direction of the turn and particular attention must be paid to the following points : !•—Very slight movement of the rudder when initiating the turn and a definite and coarser movement in conjunction with aileron movement when recovering. (If the turn becomes too steep, the correction must be made similarly.) 2. -Do not hold off bank. This is mo c important and must be remembered especially when the airspeed has risen above 70 m.p.h., as holding iff bank is almost instinctive when the stick is drawn back to decrease airspeed in a gliding or descending turn. The stress which has been laid upon this last point may puzzle certain readers. It will probably be sufficient at this juncture to say that if the practice of holding off bank in gliding or descending turns is carried to extremes, it is sufficient to induce a spin. The subject will be fully covered in a later article dealing with spinning.