VTOL at Farnborough
By OLIVER STEWART
TN March, Dr. Kiichemann, of the Royal Air- 'craft Establishment, said that the art of flying had been invented independently four times, by different kinds of animal at different stages of evolution : the insects, the saurians, the birds and the bats. Aeronautical engineers have mostly contented themselves with only two kinds of air- craft, helicopters and fixed-wing aeroplanes, but this year's Farnborough collection suggests that they are now looking farther afield. They are in- venting new kinds of flying machine. Most of the new vertical take-off and landing aircraft to be shown there—the Bristol 192, the Saunders- Roe P531 and the Westland Westminster—use moving wings, or rotors, with which to row them- selves through thesky. The Fairey Rotodyne uses a combination of moving and fixed wings; and the Short SCI (which may not be ready for the flying display) uses a combination of direct jet lift and direct jet propulsion.
They .are trying to make available in the same vehicle the extremes of aircraft performance; high speed and low speed. The objective is an airliner which will crnise at the speed of sound, yet land and take off without running half-way across England in the process; in short, a Mach 1. VTOL aircraft.
When they are not cruising, conventional air- craft and motor-cars are so much litter. They are 'miscellaneous rubbish' cluttering up acres of roads and runways. A modern airliner in the act of landing is a moving monument to aero- dynamic obtuseness; for it carries power 'plants yet cannot use them directly for the generation of lift. It must take a tangential landing as if it were a motorless glider. Birds are not such fools. When landing they pour all the power they've got into the circumambient air, obtaining a direct purchase which enables them to touch down on a twig. Two obstacles hinder aircraft designers from doing likewise: first, the action of governments, and, second, the technical difficulty of marshalling the air which circulates around an aircraft and of ushering it in the right direction so that for all flight conditions the required balance is struck between lift and forward propulsion. It can be done by slots and flaps and fans and rotors and ducts and swivelling wings and engines; but the mechanisms are always expensive and usually heavy.
The easiest way of Makiitg an aeroplane go faster is to make it run.fartlier when taking off and when landing. That isthe way Gustav Hamel did it with his Morane monoplane in 1913; that is the way they do it today. And that is the way that is encouraged by governments all over the world. The taxpayer's money has been devoted to providing enormous runways for these in- trinsically disabled airliners with high wing load- ings and high landing speeds. London Airport will soon have cost £40 million and Gatwick £20 million and neither has a runway long enough to meet the requirements of the latest and biggest Jet-driven airliners when working at full load. Both Boeing and Douglas have issued figures con- firming this. The taxpayer will have to find more money for yet longer runways. Nobody thinks of asking the airline operator to find the money.
Although he pays for them, the ordinary citizen with a light aeroplane is not allowed to use these runways without special permission. They are a free gift to the big operator who is allowed to use them in return for a landing fee. He cannot be blamed, therefore, if he is not particularly in- terested in vertical take-off and landing. There is no point in trying to do things the hard way when the taxpayer helps him to do them the easy way.
It is to the credit of the aircraft industry that, although tempted by these means to forget about take-off and landing performance, it has continued to 'work on VTOL aircraft. And there is great promise in the fact that the gap between the top speeds of VTOL aircraft and conventional aero- planes is being narrowed. Dr. Hislop's forty- eight-passenger Rotodyne, for instance, can take off and land vertically and hover as a helicopter, Yet, by virtue of its unique mingling of. the fixed wing and the AUtogiro forms of flight, it can attain a speed about 80 kilometres an hour faster than the fastest conventional passenger- carrying helicopter.
So many muddled statements have been made about the Rotodyne's method of flying, some in publications that ought to know better, that I would emphasise that, in forward flight, the freely windmilling rotor contributes to the lift in com- pany with the fixed wings and that the Rotodyne does not at any time fly in the same way as a conventional aeroplane.
The SC1 is the outcome of Dr. Griffith's work which began with the Rolls-Royce flying bed- stead. Here there seems to be a fair chance of obtaining vertical take-off and landing, yet not sacrificing top speed. A battery of lightweight turbojets does the vertical lifting and another turbojet does the forward propulsion.
It is basically uneconomic, however, to carry two entirely separate power plants, one for verti- cal lift, the other for forward propulsion, and here Count Zborowski's C-450 shows a theoretical advance. This is the extraordinary French SNECMA Coldoptere, Which consists of a turbo- jet engine—the 'flying Atar' seen at, the Paris Salon last year—standing on end with a pilot's cockpit at the top and surrounded by an annular wing. The whole thing stands on the ground on short, spindly legs, looking exactly like one of those old-fashioned annular urinals still to be seen in some parts of London. After vertical take-off the Coldoptere curves over to horizontal flight, the pilot's chair swivelling simultaneously so as to keep him upright. So the same power plant lifts and propels.
Besides the Hislop, Griffith and Zborowski methods of bringing together high top speed and vertical take-off and landing, there are methods using suction as in Dr. Lachmann's Handley Page design, a deflected slipstream and tilting wings and engines. Charles H. Zimmerman, of the National Advisory Committee for Aeronautics, who was originally responsible for the ingenious little ducted fan 'flying platforms,' has suggested that a thirty-six-ton aeroplane with four turboprops and twenty small turbojets could be made which would cruise at 560 - kilometres an hour (350 m.p.h.) at 6,000 metres (20,000 feet) yet be able to approach for landing at only 70 kilometres an hour (43 m.p.h.) on a 8 : 1 path. By blowing air from slots an airliner might be made, also capable of a nearly vertical take-off and 'landing, which would cruise at 650 kilometres an hour (400 m.p.h.).
There is no further doubt that the Mach 1, VTOL airliner is a practical poSsibility. Experi- mentally it exists already. There is no doubt that it would be basically more economical, safer and kinder to the countryside than present conven- tional airliners. But it is not likely to go into production and into regular service while govern- ments use the taxpayer's money to bribe manu- facturers not to make it and operators not to use it.
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