Flight, February 1937

THE MILES WHITNEY STRAIGHT
A Wide Speed Range, Vic<...> Characteristics and Studied Comfort in the Latest Addition to the Owner-Pilot Class: Flying a Machine With Dual Personality

   EVEN the few enthusiasts who had a chance of flying with Mr. Miles many months ago in the prototype should be agreeably surprised after a few circuits in the final and irrevocable production model of the Miles Whitney Straight. And those who always expect the impossible from an ideal light aeroplane will not find much of which to complain. We have all been waiting a long time while improvements and alterations were being made, but the production model, it seems, is likely to make this wait worth while.
   Nothing in this world is perfect - and certainly no vehicle, whether on land, on sea, or in the air, can ever be foolproof. But within the limits imposed by present-day knowledge of aircraft design the Miles Whitney Straight appears to be the last word in viceless compromise. It is fast for its power and accommodation, yet it lands at something rather less than 40 m.p.h. and can be flown in any reasonable attitude at its slowest speed without evincing any noticeable tendency to turn and bite.
   It will stall - an undisturbing business, which is announced by gentle shudders and, sometimes, by a kick of aileron - and, like everything else with wings, it will probably spin. But I should hate to supply the superhuman provocation in the matter of loading and control movement necessary to produce this second effect. Without such provocation it would seem that the very worst result of chronic mishandling by a moron novice would be a graceless and expensive descent, on a more or less level keel, into the ground, or a 40-m.p.h. collision with some continuously visible object.
   Nor let me risk the raucous laughter of the cynics by saying that any fool can fly it. Like every other aeroplane - and perhaps more than any other - the Straight requires knowing before the best results can be obtained. Without forewarning, the machine can be flown like any other, but the knowledge necessary for obtaining these better results is of a mental rather than a manual kind. It can be piloted more or less successfully by the book (pressing, so to speak, buttons "A" and "B") and by the exercise of normal height-and-distance judgment which can only be obtained by experience. In so far, the operation resembles that of driving a car, though while on the ground the newcomer must learn to steer with his feet; in the air he can forget these clumsy extremities.
   Before taking the machine up to see for myself, I witnessed two interesting performances - one from the ground and the other from the passenger's seat. In the first a man who had had a great deal of flying experience, but who had never actually touched the controls of any aeroplane, was being given a try-out. His first two landings would have been wreckers without the help of a burst of motor applied by Mr. Miles after the impact; his third was very fair, and certainly safe. On this third round he took off, made a circuit, closed the throttle, and landed without any assistance other than verbal (and little of that). His departure left a zig-zag pair of wheel-tracks, and his arrival was off-wind - results largely of an inability to use the unnatural rudder control.
   In the second performance Mr. Miles showed me just what could be done with impunity. I was frightened most of the time - but I should have been dead after being frightened in the majority of machines. His hands-and-feet-off landing is a rather obvious trick, but it does show that the machine is extraordinarily stable at slow speeds in all three axes, that the undercarriage will take its medicine, and that Mr. Miles is encouragingly confident in the machine's ability to do it properly every time. It is, as may be imagined, made possible by a combination of skilful trimming, inherent stability, and low-wing cushioning effect.
   To the pilot the most remarkable feature of the machine is its wide range of approach angles. When making about eight or ten approaches I closed the throttle while flying down-wind, while approaching up-wind and nearly over the aerodrome boundary, and while travelling at cruising speed with the aerodrome almost out of sight in the prevailing bad visibility. In each case I got into the aerodrome quite comfortably with the exercise of normal powers of judgment and while making full use of the machine's Jekyll and Hyde characteristics. On the final four attempts I pulled off unassisted spot landings just over the marker boards. Incidentally, it was not until later that I discovered that this particular “spot” was about the roughest part of the aerodrome - a sufficient tribute to the excellence of the undercarriage.
   This range of angles is a product not so much of the use of the flaps in either position, but of the machine's gliding characteristics at different speeds. The slower the glide the steeper the approach. If, during a straight, fully flapped approach at 60 m.p.h., it is seen that the aerodrome is being overshot, all the pilot does is to ease the stick back a little until the machine is sinking rather than gliding - and yet sinking under full control. At the lowest limit, 40 m.p.h., and gliding into anything of a normal breeze, the approach angle appears to be of the order of one in one.
   The danger of making too great a use of this very steep approach is one of undershooting, since height is rapidly lost, particularly during the final semi-dive to gather a little safe speed for the hold-off and landing. While it is possible to land straight off a 50-m.p.h. approach, a little more speed is desirable if minor misjudgments in hold-off are to be counteracted and if full aileron control is to be retained for bump correction near the ground. Needless to say, the motion of holding-off at, say, 42 m.p.h.; would, while momentarily lifting the nose; merely precipitate the machine into the ground in a level attitude. Though the cantilever undercarriage legs have 5 1/2 in. of useful movement and are designed to take a vertical velocity of 15 ft./sec, such a performance is not to be recommended.
   If there is doubt about the machine's ability to reach any particular aerodrome or field, the flaps need not be lowered at once, and in a very strong wind it is probably better to use the half-way position throughout the approach. Unflapped, the Straight has the flattest of glides. In this connection, two points are worth mentioning.
   The flaps are pneumatically operated by Simmonds-Theed control with a vacuum tank in the circuit; in the half position the outer portions move down, while in the full position these portions are balanced by the section beneath the fuselage, this section being hinged at the rear. For purely mechanical reasons it is not possible to move the flaps from the full to the half position, and if the pilot wishes to retract them partially he must first move the finger-light dash lever into the "off" position. In the other, and more usually necessary direction of application, he can obtain both positions in sequence. The second point is that, if the engine stops, the vacuum tank will perform two complete flap movements under load, so that, if the worst comes to the worst, a forced landing glide may be stretched. The use of the flap control for such a purpose is not recommended in the ordinary course of events - for reasons, mainly, of stalling-speed alteration and of slight changes in the gliding characteristics.
   Contrary to the statement in the preliminary leaflet, the flaps do not come up of their own accord when the throttle is opened fully for a second approach attempt, but the machine flies and climbs quite normally, though at very low speeds, with the flaps down ; in these circumstances the best climbing speed is as low as 45 m.p.h. I did one flap-down take-off and found that the run was very little longer than normal, though the air speed indication afterwards showed no tendency to rise and the machine felt as one on which the revolutions had suddenly dropped. If, by any chance, a take-off is accidentally started with the flaps right down, the fact is made obvious before flying speed is reached by a sudden release, at about 30 m.p.h., of the load on the stick, which is still being held forward - an effect probably caused by reflected downwash.

Special Technique

   Although the actual take-off run is not appreciably shortened by using the flaps in the half-down position, this position can be used for small-field work, provided that the technique is thoroughly understood and practised. In short, the effect is one of providing flapped characteristics without suffering any marked drag. With the flaps down, considerably greater liberties can be taken at low speeds and the stalling speed is, too, slightly lower.
   In normal flight one develops the habit with the Straight of placing the feet firmly on the floor and of ignoring the rudder. Perfect turns can be made on the stick alone, and even steep turns can be changed over without any marked movement of the lateral bubble from its central position, provided that the manoeuvre is carefully carried out. The ailerons are particularly smooth, effective and light, and semi-aerobatic flying is made very pleasant indeed. Minor corrections in course and lateral level can be made on the rudder alone (while eating one's lunch or working a C.D.C.), and in smooth air the machine will probably fly more or less indefinitely hands and feet off - though a period of 4 1/2 minutes was the longest during which I found myself able to leave the machine alone. The ability in my case was limited by visibility and a consequent fear of losing myself in the Reading area. Cabin silence nowadays is expected rather than praised, and the Straight is well up to standard in this respect.
   Familiar Miles construction is used throughout the wooden air frame and, apart from the special care exercised in both internal and external work, there is nothing out-of-the-ordinafy about the machine.
   The engine cowling is a centrally hinged two-piece affair and either side may be propped up by two struts which normally lie in a clip along the top engine bearer; this little feature should save a fortune in hat cleaning. The normal tank capacity is thirty gallons, providing a still-air range of 570 miles, but special tanks, carrying a total of forty-five gallons, can be fitted if desired. A single electric dash-gauge is used for reading off the contents of either tank at will.
   While in flight the range of vision from the cabin is exceptionally good, and is limited only by the nose and the low wing. Before opening up for the take-off the sky behind can be examined without difficulty or neck strain, and the one-piece Perspex windscreen gives one as much general forward vision as is humanly possible in any nose-engined machine. Whether or not this somewhat expensive moulding will require replacement after, say, a year's flying remains to be seen.
   Behind the wide one-piece seat there is a vast area for luggage accommodation, complete with straps, and on the rear bulkhead there is a hat rack. This will undoubtedly be used for a host of oddments which cannot comfortably be kept in the two cubby-holes in the dash.
   It is difficult to see how entrances and exits can be made easier in the low-wing type of machine in which the occupants are placed well forward, but, with a pair of control columns and what not, the job is somewhat contortionist. Furthermore, an inexpert passenger will undoubtedly place muddy shoes on both seats at least once before he or she is finally in place. In this connection one wonders why the door-cum-roof is on the port side. Nobody cares about the pilot's feelings, but everyone cares about those of a passenger - particularly one who has never flown before - and it is the pilot who usually stays in his place. The pilot, too, will soon learn to enter gracefully, and will be less likely at any time to put his foot through fifteen pounds-worth of compass and dashboard. When closed, the top is brushing the pilot's hat (for the short pilot will probably demand a cushion in order that he shall have the maximum visibility), but this is probably an advantage, inasmuch as there is a shorter body movement in an unexpectedly bad bump.
   These, however, are very small points of criticism when examined beside the remarkable efficiencies of this new private-owner type. Even at its comparatively high price, it is likely to hold a definite place for itself during the next year or two. Then, perhaps, the Miles Whitney Straight II will be coming along.

THE MILES WHITNEY STRAIGHT
130 h.p. D. H. Gipsy Major Engine

   Span 35.8 ft.
   ,, (wings folded) 17.2 ft.
   Length 25,0 ft.
   Height 6.6 ft.
   Cabin width 43 in.
   Weight, empty 1,250 lb.
   ,, loaded 2,000 lb.
   Maximum speed 145 m.p.h.
   Cruising speed at 1,000 ft. and 2,100 r.p.m. 130 m.p.h.
   Stalling speed (flaps down) 38 m.p.h.
   Range in still air (standard tanks) 570 miles
   Take-off run (5 m.p.h. wind) 145 yds.
   Landing run (5 m.p.h. wind) 100 yds.
   Initial rate of climb 850 ft./min.
   Price ex works ?885
   Distributors: Whitnev Straight, Ltd., Brettenham House Strand, London, W.C.2.