HAL HUL-26 Pushpak

В 1958 году компания HAL приступила к работам по проектированию легкого учебно-тренировочного самолета, который предназначался для индийских летных школ и аэроклубов. Самолет получил обозначение HUL-26 Pushpak - первый прототип совершил первый полет 28 сентября 1958 года. Самолет представлял собой моноплан смешанной металлической и деревянной конструкции, с полотняной обшивкой, с высокорасположенным расчалочным крылом и неубираемым шасси с хвостовым колесом. Следом за прототипом построили еще около 160 таких самолетов, которые отличались в основном металлическим, а не деревянным крылом.


ТАКТИКО-ТЕХНИЧЕСКИЕ ХАРАКТЕРИСТИКИ

   HAL HUL-26 Pushpak

   Тип: двухместный учебно-тренировочный и спортивный самолет
   Силовая установка: один ПД Continental C90-8F мощностью 90 л. с. (67 кВт)
   Летные характеристики: максимальная скорость на уровне моря 145 км/ч; крейсерская скорость на оптимальной высоте 137 км/ч; начальная скороподъемность 152 м/мин; практический потолок 4270 м; дальность 402 км
   Масса: пустого 395 кг; максимальная взлетная 612 кг
   Размеры: размах крыла 10,97 м; длина 6,40 м; высота 2,77 м; площадь крыла 16,26 м2

Flight, September 1938

C.A.G. INVADER
Some Impressions of the New Aeronca Chief : A Typical American Miniature

   BOTH in flying characteristics and layout the American private-owner type is still very different from those of the typical English machine. Curiously enough, too, the features of the American car, in comparison with that built in England, are very similar in a distinct but quite undefinable way. In the larger classes the American machine has been developed around a power unit of a size which would normally be hopelessly uneconomical over here, and the comparatively new series of lightweights from the same country are tending to follow similar lines, with full-scale control systems and comfortingly familiar interior layouts.
   There are three American lightweights available over here which are suitable, in weight and general features, for C.A.G. use. These are the Piper Cub, which is handled by Mr. Walter at Hanworth; the Taylorcraft, which is being demonstrated by Mr. Prentice at Ipswich; and the new Aeronca, the agents for which are Aviation Equipment and Export, Inc., of 14-16, Regent Street, W.1.
   All are interesting, the last-named because it is the first to be flown in this country with one of the new 50 h.p. Continental flat-four engines. Theoretically, this engine merely gives ten more horse-power than its forerunner, but in practice it is a very much more useful engine. Because its revolutions are low as aero engines' speeds go - 1,995 r.p.m. maximum and 1,700 r.p.m. cruising - the airscrew efficiency at low flying speeds is high and the acceleration, take-off and climb effects are such as one might expect with a unit of much higher power. The new engine, save for the fact that it is again a flat-four, is also radically different in design, with overhead valves and hydraulic (self-adjusting) tappets.
   In the Aeronca this new engine is completely cowled-in with a proper "built-in" cooling system, and this cowling gives the nose of the machine a clean form which probably helps quite a lot in providing the machine with a performance which, on such a low power, is quite remarkable when allied to an exceptionally low - almost too low - landing speed. The official cruising figure is 90 m.p.h. and A.S.I. readings, in practice, suggest that this is not exaggerated.
   So far as the cabin layout is concerned the Chief may adequately be described as a miniature Stinson. The ailerons are wheel-controlled, with the operating mechanism and column hidden behind the dashboard, leaving the floor space clear except for the rudder and brake pedals. It is, in fact, quite possible to change seats while flying solo. The plunger type throttle is centrally placed, though it is possible to work it with one's left hand while sitting on the left side. The trimming crank is in the roof.
   Altogether one might justifiably say that the control system, delightful though it is for those who have had previous experience of wheels and right-hand throttles, will offer the only point of criticism from the club members’ angle. The ab initio pupil will probably have less difficulty than with the more conventional layout, but he will certainly not find it so easy to transfer, in due course, to an orthodox machine. The pupil who has learnt on conventional types may require about an hour’s dual to become accustomed to it. One is not saying that this control arrangement is anything but more natural than the usual one, but merely that, over here, it may be a slightly unhappy feature of an otherwise suitable machine. In fact, the new Aeronca will provide excellent training for pilots who are going on to larger machines with a similar layout and side-by-side seating.
   In comparison with earlier American types of a similar kind, the machine is tremendously improved. The cabin is really roomy for two normally sized individuals, and there is plenty of head space. The sliding windows on each side can be kept open in hot weather without causing any uncomfortable draught and the one-piece windscreen remains properly transparent in rain. The view on the ground is not perfect, though it is possible to see out on each side with a little neck-stretching. Once in the air, however, the top of the cowling is very well below the horizon. There is a door on each side and quite a reasonably capacious luggage compartment immediately behind the rear squab.
   Nothing could be easier to fly in the ordinary way. The machine is thoroughly stable in all axes and will turn with moderate accuracy on either the ailerons or the rudder alone. During the take-off very little rudder correction is necessary, and the run is so very short that it is impossible to imagine any difficulties. The fore and aft trim is carried out by means of a tab in the elevator, and the crank movement involved must be thought out until one has become accustomed to the machine. With two up there is ample trimming range, but with only the pilot aboard the natural hands-off gliding angle, with the trim wound right back, is a little steep unless the pilot is fairly weighty.
   The machine side-slips with commendable verve at all speeds, and for small field approaches it is possible to hold quite a steep slip at an airspeed of 50 m.p.h. or less. This, too, is the best gliding speed. If one comes in at, say, 60 m.p.h. the hold-off is a trifle prolonged, and the change in the feel of the fore-and-aft control is somewhat marked as the speed comes down. At a certain point this control becomes lighter, while remaining almost equally effective, and the result is quite invariably the pulling of a quick pint or two while the pilot accustoms himself to the new circumstances.
   The last part of the approach and the landing may best be described by saying that, though it is difficult to pull off a really good landing, it should be impossible to make a really bad one. The elevator control is just too powerful at low speeds and the landing speed itself is so low that one is inclined to attempt a premature three-pointer. There is, however, so much reserve buoyancy that one can do almost anything even at 40 m.p.h., and still finish up with the machine properly and firmly placed on the ground - more or less at a standstill if there is any wind at all.
   The statement that it is impossible to make a really bad landing is made as a result of due experience. When I first flew the machine the carburettor setting was incorrect, and at any air speed below 60 m.p.h. it was necessary to use some throttle to keep the engine going. The result was that either the landing process was upset by last-minute throttle manipulation or was considerably prolonged because the throttle was left open. A really good landing in such conditions is virtually impossible. One may also add that in these circumstances the undercarriage was tested and found adequate to deal with mediocre landings.
   Later on, when the carburettor had been duly attended to, it was possible to discover just how slowly and accurately the machine could be brought in. Certainly, the Chief can be considered as an excellent small-field type for the pilot who knows it. The braking system is controlled in the usual American way, through a pair of heel pedals below the rudder pedals. This, again, requires practice for accurate operation, but the knack is soon learned. No parking brake is provided and this fitting is missed when attempting to start the engine single-handed; even on a small throttle opening the machine, fitted as it is with a tail wheel, may start a gentle, if harmless, roll.
   The structure of the Chief is conventionally American, with a welded steel fuselage suitably faired by means of ply-wood and stringer-supported fabric, and two-spar fabric-covered wooden wings.
   H. A. T.

AERONCA CHIEF
50 h.p. A.50 Continental Engine.
Span 36ft.
Length 21ft.
Weight empty 650 lb.
All-up weight 1,130 lb.
Maximum speed 100 m.p.h.
Cruising speed 90 m.p.h
Landing speed 32 m.p.h.
Rate of climb at sea level 550ft./min.
Surface ceiling 14,000ft.
Cruising range 250 miles.
Price £498.
Concessionaires: Aviation Equipment & Export Inc., 14-16, Regent Street, London. W.l.