BRITISH AVIATION NEWS

Otago Daily Times, Issue 21627, 23 April 1932, Page 15

BRITISH AVIATION NEWS

AEROPLANE AND MOTOR CAR f ‘.. “ ■' ' ■ ■ : iC;;..* 5 '...' ; —— TORPEDO BOMBERS FOR DANISH D" ' MARINE; (From Our Own Correspondent.) jr ' ' ’ LONDON, March 9. , Thai the' present-day light aeroplane costf no more to run than a 20 h.p. motor car Av'as proved satisfactorily the other evening by the Master of Sempill, himself a leading owner-pilot and aeronautical expert, in a lecture before the Royal Empire .Society. He assumed that aeroplane and motor car each’travelled 12,000 miles in a'given year. I’he total cost, excluding depreciation, he gave, as £205 for* the motor car and £:208 for the flying machine. Expenditure ,on petrol and oil was approximately level at around £4O. The. car tax was £2Q, and the-aeroplane five guineas. Tyres cost £lB on the car and only £3 12s 6d on , the aeroplane, Maintenance at £O4 las for the motor car was £5 less than for the aeroplane. Housing was exactly the same at £39. The chief difference shown was in the cost of inaurplane. ; > - These figures should dispel the widespread belief that the private aeroplane is only for the rich. A further important point is- that, practically speaking, an aeroplane is always in ‘. new ” condition. The strict airworthiness regulations provide for severe inspection and overhaul at stated intervals. when every defective part must be replaced and all repairs done up to the : standards'of the original construction.-: Often,-too, modifications decided by the makers'are blade compulsory in machines already in use before a new Certificate of airworthiness-can be granted. Tims, depreciation in an aeroplane is much less than in a motor car, and second hand prices are relatively much higher.

DENMARK’S' NEW TORPEDOPLANES. British torpedo bombers similar to machines employed in three squadrons of the Royal Air Force are to be constructed under license in the dockyard of the Danish Department of Marine —a fresh tribute to the high reputation of British military aeroplanes. The craft are . big biplanes of the Hawker “ Horsley ” type, but fitted with the Armstrong Siddeley 800 -h.p. “ Leopard ” motor, the most powerful aircooled unit yet in production anywhere in the world, instead of the water cooled engine , which provides power for the “Horsleys” in the British service. They can carry an exceptionally heavy load and are able to hold the air for many hours; a Hawker “Horsley” biplane established in 1927 a British record for distance flown non-stop by flying 3400 miles in 344 hours from England to the Persian Gulf, The “service” load of the Danish machines will bo no less than 47001 b, 21501 b of which is the weight of the big torpedo carried in launching gear under the fuselage. The “ Horsley ” is ‘ intended primarily for coastal patrol and attacks on ocean warships, its maximum speed is around 130 miles per hour, and, in spite of the heavy load, it can climb 6000 feet in eight minutes. Capacity for long flights is essential, because torpedo bombers would be sent on occasion against surface ships which were far out to sea. The torpedo is launched in a dive which brings the aeroplane down to a height of 100 or 200 feet above the water; a high rate of climb is therefore necessary to carry the machine swiftly 'out of the range of the anti-aircraft batteries on the menaced warship. ENGINE “LIFE” AND ECONOMY. Two aero engines stripped right down to the smallest details and laid out for inspection in the Rolls-Royce works at Derby fix the admiring attention of every technical visitor, and not least of the high officials of the French Air Ministry who examined them a little'while ago.' One of them* is a 480 h.p. “ Kestrel ” engine which has flown 452 hours in a fast “Hart” day bomber without any overhaul; the other is the 2560 h.p. engine which drove Flight Lieutenant Staiuforth’s

racing seaplane over the speed course last September at the world’s record speed o£ 407.5 miles an hour. Both engines are in practically perfect condition, the racing' unit so untouched by its two hours of terrific life that the mechanics who took it to pieces thought at first that the wrong engine must have been sent back to the works.

Y.et during Stainforth’s full throttle power dives on to the speed course, this engine, producing nearly 2600 h.p. from a mass of metal only 16501 b in weight, was turning at the tremendous speed of 3400 revolutions a minute. But of that great effort, meaning the subjection of main components to loads amounting to many tons per square inch, no single part shows the slightest trace. Equally remarkable is the much used “ Kestrel.” In 18 months it has flown something like 60,000 miles without even a partial, or “top,” overhaul; the condition of the parts proves that it could have been used for many tens of hours longer without fear of trouble. Anfl this particular unit is not exceptional; many similar engines which have done well over 400 hours in service squadrons are now coming into the works for inspection and overhaul and all show an exceedingly small percentage of wear and tear. Probably the period between overhauls of these engines will soon be extended as a general rule to 450-500 hours, figures which are not nearly approached by any foreign-built engines used in the fighting air services of other countries.

The inevitable corollary of this order of “life” and trustworthiness is that few spare parts arc required. 1 ’ Original Air Ministry estimates of the spares necessary have been dractically cut down. Even to-da'y the maximum “ life ” attainable is not yet known and may be considerably higher than 500 hours. No wonder the French exports were impressed.

TRAINING THE FIGHTING PILOT

Far on in the training of the budding pilot of a single-seater fighter comes the stage when he knows all about general principles and is ready for initiation into those finer points of aeroplane handling which are especially important in the pilotage of the swiftest and most responsive of all types of war machine.

For this duty aeroplanes like the two'

seater “ Bulldog ” are frequently employed. This two-seater is in essentials exactly similar to the “ Bulldog ” fighters which are used extensively in the Royal Air Force and in the air services of eight other countries. The chief modification, apart from the provision of an extra cockpit, is the stripping of the armament —guns, bombs, gun gear, and rings and ammunition boxes. At need, the machine can be readily converted for fighting use by covering over the rear cockpit and replacing the armament. The two-seater “ Bulldog " is capable of speed and rate of climb almost identical with the single-seater which, in its standard form, with a 450 h.p. supercharged “Jupiter” motor, attains a maximum speed at a height of 10.000 feet of nearly three miles a minute. High tensile steel tube and strip are the .materials chiefly employed in the construction.