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Aviation History
1961
1961 - 0359.PDF
FLIGHT, 23 March 1961 PRIVATE AND EXECUTIVE FLYING... 367 What's this One-eighty Rating? AOPA s 180° RATING HANDS Off CONTROLS CENTER SEAR DOWN THROTTLE RACK TRIM TO MARK THROTTLE , The life you CENTER CENTER CENTER HIGH R.F.M. CENTER NEEDLE NEEDLE NEIDLE NEEDLE NEEDLE save fill be your own IN Beech Bonanzas and Beech Debonairs sold in the UnitedStates—and perhaps in other types besides—the instrumentpanel bears the placarded instruction:— IN CLOUDS USE RUDDER PEDALS ONLY AND MOVE THEM GENTLY. DO NOT TOUCH WHEEL OF CONTROL COLUMN UNTIL YOU BREAK OUT BELOW CLOUDS. TO DO SO IS TO INVITE INVOLUNTARY AEROBATICS AND A FATAL ACCIDENT. What extraordinary doctrine is this, which apparently offendsagainst the most basic tenets of instrument flight? As all pilots with instrument experience will know, the first precept of straight-and-level blind flying is to centre the turn needle—and then to get the aircraft in balance by checking slip and climb or descent. But the point of these instructions is that they are designed forthe pilot who has no instrument experience at all, and who, having entered cloud, wants safely to leave it as quickly as possible. Thisis the aim of the 180° rating, a technique pioneered by the US Air- craft Owners and Pilots' Association and developed for them by theInstitute of Aviation of the University of Illinois. Not by any stretch of the imagination instrument flying, it is acrude but effective procedure which enables the non-instrument pilot, with a minimum of training, to retain control of his aircraftin instrument weather and descend or fly back into the clear. And in spite of years of opposition from those who considered that "alittle (instrument) knowledge is a dangerous thing" its vindication became absolute when, last year, it was adopted by the FAA as astandard requirement for a US private pilot's licence. The technique depends upon an aircraft's inherent stability. Theonly control surface used is the rudder, and the only flight instru- ments the turn needle and magnetic compass. On entering cloud,or otherwise losing "contact," the pilot keeps the turn needle centred. He then takes his hands off. This is to avoid the dangerof overcontrolling; the aircraft is left to find, through a series of phugoid oscillations, its natural trimmed speed. Next, the pilot lowers the undercarriage, even if the aircraft isabove normal gear-down speed. (An exception to this would be made were it structurally unsafe.) This is to increase drag and reducethe possibility of gaining excessive speed. Then, power is reduced to just above idling, and the trim is adjusted to a position for lowsafe speed on full aft e.g.—something between approach speed and about 2Vs. It is an important part of the technique that this trimposition should be pre-marked; similar marking is required for the throttle, which is then moved to a position that will give sufficientpower for height to be maintained. With a variable-pitch propeller, the pitch should be fully fine (max r.p.m.). Each of the foregoing steps will be accompanied by a change oflongitudinal trim. All are ignored; the 180° rating pilot is taught to minimize them by following through each step in turn withouthesitation. All the while, the turn needle must be kept centred, or in rough weather, the average of swings must be balanced out. With the aircraft in balance, heading is read off and the reciprocalnoted. A rate 3 turn through 180° is then started on rudder alone, and at as nearly a constant rate as possible. Less than a standardrate of turn is used to reduce bank angle and centrifugal loading. The reciprocal heading is regained by ruddering-out with appro-priate lead or lag to compensate for turning errors of the magnetic compass. This should bring the VFR pilot back into the clear. Ifafter a few minutes it does not, he continues with the procedure, reducing power to give a 400-500ft/min rate of descent—if necessaryright down to ground level. A VFR pilot caught out in instru- ment weather may thus stand a better chance of survival than byattempting to flv on his basic instruments. Just how little chance of success instruments give an untrained pilot is shown by tests conducted by the Institute of Aviation on 20non-instrument pilots, some with well over l,000hr experience. "Nineteen subjects," says their report, "placed the aircraft in agraveyard spiral on their first attempt to fly by instruments. The twentieth pulled the aircraft up into a whip stall. Minimum time toreach an incipiently dangerous attitude was 20 sec; maximum was eight minutes." The average was two seconds under three minutes. Total time required thoroughly to train a pilot in the 180 ratingtechnique is about six hours. The first part of the training consists of allowing the pupil, in an aircraft equipped with blue goggles andamber screens, to try instrument flying for himself; he is rescued before hitting the ground. But not too soon before, because it isregarded as essential that every pilot should be allowed to convince himself that he cannot fly on instruments without special trainingand practice. Then he can be taught the rating technique of keeping the aeroplane under control—the sloppiest kind of control, butnevertheless under definite control. Is there a place for the 180 rating in Great Britain? It may wellbe that there is. There may not be much reason to enter instrument weather when flying just for fun, but on business journeys thetemptation to press on when contact is lost is a real one. And with an instrument rating so far out of reach for most amateur pilots,should not Ministerial approval be given to a simple life-saving procedure ? It Works in Practice The FAA have developed in recent trials an effective controlled-descent system in which the pilot uses only these 180 -rating tech- niques—a trimmed, hands-off let-down in which heading is adjustedonly by rudder movements and by reference to a turn indicator or directional gyro. The pilot prepares for the descent from 1,500ftabove cloud by slowing down, lowering flap and undercarriage, and following a step-by-step procedure given over the radio by theground controller. On 98 of 102 test let-downs by 54 non-instru- ment pilots the technique worked successfully. No such get-you-down procedure is available in Great Britain, although opportuni- ties for error are just the same. The only possible alternative, aGCA or QGH let-down, demands a certain competence at instru- ment flying. It may of course be argued that provision of such emergencyprocedures undermines the value of a proper instrument rating, and that a 1801 rating training would only encourage private pilots toexceed their own limitations. This is what Max Karant, vice- president of the AOPA, has to say on the subject:— "You would think that such proven, simple safety techniques would beeasy to sell. Unfortunately, history has once again repeated itself. The hardest commodity we in aviation have to sell is safety. There aresafety devices, safety techniques, safety know-how—all readily available, but not saleable. Examples: shoulder harnesses, cabin structuresdesigned for maximum occupant protection, stall-warning equipment, cross-wind landing gear—and the 180° rating. At the moment, wehave 87,000 paid-up members, all of them pilots and/or aircraft owners. We have continuously bombarded them with information on the tech-nique which they actually paid for. And yet, only a total of 1,040 AOPA members (including instructors) have qualified in six years." The FAA's predecessors, the CAA—who had been watching thedevelopment closely—eventually took a hand, and when the FAA was founded they made new requirements for a private pilot'slicence (based on the same 180"-rating techniques) into law. ''Why the indifference during the voluntary programme?" asksMax Karant. "A major factor was, I think, the strong opposition to the entire concept by professional flight instructors. To them, the180° rating (and now the FAA requirement) are a far greater hazard than the hazard they set out to cure. They take the positionthat 'a little knowledge is a dangerous thing," and that pilots so trained were sure to go out and try instrument flying and get them-selves killed. The record does not support this. As I wrote several times in answer to the contention about 'a little knowledge'—'if a little knowledge is a dangerous thing, show me a man who is safe.' " Is the 180° rating a hazard, or a hazard cure ? Something to helpthe foolish or unlucky amateur or inadequate and dangerous education in instrument flight? The FAA have made up theirminds—and they have a habit of being right. ALASTAIR PUGH
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