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Ответ: Отчет по испытаниям Bf-109E3 (обещал)
Прочитал перевод из аэромастера. М-да. Ошибок перевода и просто ошибок там такое количество, что куда там мне. Посему, вот в оригинале текст по управляемости. Т.с. для самостоятельного изучения.
On May 4, 1940, a Bf.109E (Wn: 1304) was flown to RAF Boscombe Down, where it was appraised by the Aircraft and Armament Experimental Establishment (A & AEE); then later flown to the Royal Aircraft Establishment (RAE) at Farnborough for handlin gtrials, and allocated the serial number AE479.
Take-off
This is best done with the flaps at 20 degrees. The throttle can be opened very quickly without fear of choking the engine. Acceleration is good, and there is little tendency to swing or bucket. The stick must be held hard forward to get the tail up. It is advisable to let the airplane fly itself off since, if pulled off too soon, the left wing will not lift, and on applying aileron the wing lifts and falls again, with the ailerons snatching a little. If no attempt is made to pull the airplane off quickly, the take-off run is short, and initial climb good.
Approach
Stalling speeds on the glide are 75 mph flaps up, and 61 mph flaps down. Lowering the flaps makes the ailerons feel heavier and slightly less effective, and causes a marked nose-down pitching moment, readily corrected owing to the juxtaposition of trim and flap operating wheels. If the engine is opened up to simulate a baulked landing with flaps and undercarriage down, the airplane becomes tail-heavy but can easily be held with one hand while trim is adjusted. Normal approach speed is 90 mph. At speeds above 100 mph, the pilot has the impression of diving, and below 80 mph one of sinking. At 90 mph the glide path is reasonably steep and the view fairly good. Longitudinally the airplane is markedly stable, and the elevator heavier and more responsive than is usual in single-seater fighters. These features add considerably to the ease of approach. Aileron effectiveness is adequate; the rudder is sluggish for small movements.
Landing
This is more difficult than on the Hurricane I or Spitfire I. Owing to the high ground attitude, the airplane must be rotated through a large angle before touchdown, and this requires a fair amount of skill. If a wheel landing is done the left wing tends to drop just before touchdown, and if the ailerons are used to lift it, they snatch, causing over-correction. The brakes can be applied immediately after touchdown without fear of lifting the tail. The ground run is short, with no tendency to swing. View during hold-off and ground run is very poor, and landing at night would not be easy.
Taxing
The aircraft can be taxied fast without danger of bucketing, but is is difficult to turn quickly; an unusually large amount of throttle is needed, in conjunction with harsh braking, when manuevering in a confined space. The brakes are foot-operated, and pilots expressed a strong preference for the hand operation system to which they are more accustomed.
Lateral Trim
There is no procounced change of lateral trim with speed of throttle setting provided that care is taken to fly with no sideslip.
Directional Trim
Absence of rudder trimmer is a bad feature, although at low speeds the practical consequences are not so alarming as the curves might suggest, since the rudder is fairly light on the climb. At high speeds, however, the pilot is seriously inconvenienced, as above 300 mph about 2 1/2 degrees of port (left) rudder are needed for flight with no sideslip and a very heavy foot load is needed to keep this on. In consequence the pilot's left foot becomes tired, and this affects his ability to put on left rudder in order to assist a turn to port (left). Hence at high speeds the Bf.109E turns far more readily to the right than to the left.
Longitudinal Trim
Five three-quarter turns of a 11.7 in diameter wheel on the pilot's left are needed to move the adjustable tailplane through its full 12-degrees range. The wheel rotation is in the natural sense. Tailplane and elevator angles to trim were measured at various speeds in various condition; the elevator angles were corrected to constant tail setting. The airplane is statically stable both stick fixed and stick free.
'One Control' tests, flat turns, sideslips
The airplane was trimmed to fly straight and level at 230 mph at 10,000 feet. In this condition the airplane is not in trim directionally and a slight pressure is needed on the left rudder pedal to prevent sideslip. This influences the results of the following tests:
Ailerons fixed central On suddenly applying half-rudder the nose swings through about eight degrees and the airplane banks about five degrees with the nose pitching down a little. On releasing the rudder it returns to central, and the airplane does a slowly damped oscillation in yaw and roll. The right wing then slowly falls. Good baned turns can be done in either direction on rudder alone, with little sideslip if the rudder is used gently. Release of the rudder in a steady 30-degree banked turn in either direction results in the left wing slowly rising.
Rudder fixed central Abrupt displacement of the ailerons gives bank with no appreciable opposite yaw. On releasing the stick it returns smartly to central with no oscillation. If the ailerons are released in a 30-degree banked turn, it is impossible to assess the spiral stability, since whether the wing slowly comes up or goes down depends critically on the precise position of the rudder. Excellent banked turns can be done in either direction on ailerons alone. There is very little sideslip on entry or recovery, even if the ailerons are used very harshly. In the turn there is no appreciable sideslip.
Steady flat turns Only half-rudder was used during this test. Full rudder can be applied with a very heavy foot load, but the nose-down pitching movement due to sideslip requires a quite excessive pull on the stick to keep the nose up. When flat turning steadily with half-rudder, wings level, about half opposite aileron is needed. The speed falls from 230 mph to 175 mph, rate of flat turn is about 110.
Steady sideslip when gliding Gliding at 100 mph with flaps and undercarriage up the maximum angle of bank in a straight sideslip is about five degrees. About 1/4 opposite aileron is needed in conjuction with full rudder. The airplane is faily nose-heavy, vibrates and is a little unsteady. On release of all three controls the wing comes up quickly and the airplane glides steadily at the trimmed speed. With flaps and undercarriage down, gliding at 90 mph, the maximum angle of bank is again five degrees 1/5 opposite aileron being needed with full rudder. The nose-down pitching movement is not so pronounced as before, and vibration is still present. Behaviour on releasing the control is similar to that with flaps up.
Stalling Test
The airplane was equipped with a 60 foot trailing static head and a swiveling pitot head. Although, as may be imagined, operation of a trailing static from a single-seater with a rather cramped cockpit is a difficult job, the pilot brought back the following results:
Lowering the ailerons and flaps thus increases CL max of 0.5. This is roughly the value which would be expected from the installation. Behaviour at the stall. The airplane was put through the full official tests. The results may be summarized by saying that the stalling behaviour, flaps up and down, is excellent. Both ruddera nd ailerons are effective right down to the stall, which is very gentle, the wing only falling about 10 degrees and the nose falling with it. There is no tendency to spin. With flaps up the ailerons snatch while the slots are opening, and there is a buffeting on the ailerons as the stall is approached.. Withs flaps down there is no aileron snatch as the slots open, and no pre-stall aileron buffeting. There is no warning of the stall, flaps down. From the safety viewpoint this is the sold adverse stalling feature; it is largely off-set by the innocuous behaviour at the stall and by the very high degree of fore and aft stability on the approach glide.
Safety in the Dive
During a dive at 400 mph all three controls were in turn displaced slightly and released. No vibration, flutter or snaking developed. If the elevator is trimmed for level flight at full throttle, a large push is needed to hold in the dive, and there is a temptation to trim in. If, in fact, the airplane is trimmed into the dive, recovery is difficult unless the trimmer is would back owing to the excessive heaviness of the elevator.
Ailerons
At low speeds the aileron control is very good, there being a definete resistance to stick movement, while response is brisk. As speed is increased, the ailerons bevome heavier, but response remains excellent. They are at their best between 150 mph and 200 mph, one pilot describing them as an 'ideal control' over this range. Above 200 mph they start becoming unpleasantly heavy, and between 300 mph and 400 mph are termed 'solid' by the test pilots. A pilot exerting all his strength cannot apply more than one-fifth aileron at 400 mph. Measurements of stick-top force when the pilot applied about one-fifth aileron in half a second and then held the ailerons steady, together with the corresponding time to 45 degrees banbk, were made at various speeds. The results at 400 mph are given below:
Max sideways force a pilot can apply conveniently to the Bf.109 stick 40 lbs.
Corresponding stick displacement 1/5th.
Time to 45-degree bank 4 seconds.
Deduced balance factyor Kb2 - 0.145
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