BRITISH AVIATION

Hokitika Guardian, 25 September 1931, Page 8

BRITISH AVIATION

SPEEDIER MAIL CARRYING. NEWEST CIVIL AIRCRAFT. * LONDON, August 13.. The fastest British load-carrying civil aircraft yet built, an Avro “Mailplane” I capable of flying at nearly three miles '! a minute with full load on board, was ; demonstrated on August 10 at Heston I airpark before Colonel Shel’merdine, Director of Civil Aviation, and a few privileged experts. Acceleration of air mail services throughout the world is a subject receiving nowadays marked attention in | British aviation circles, and this new craft is the first of a number of mail carriers, constructed in British works which promise spectacular progress in the development of night and day aerial mail routes. The British Empire offers a field for high-speed mail operation not surpassed in potentialities by any of the other great land areas, and leading experts consider that the employment of relays of machines similar to the new Avro plane could at once, given the essential ground organisation, reduce the time taken for the mails to travel from London to ■ Sydney,’ for example, to seven days and a-lialf.

The present controversy engages the protagonists of two theories, that mails should travel with passengers, and, alternatively, that these two main classes of aerial traffic should be separated. Supporters on the one side declare that the slowing down of mail transport to the speed made necessary by the frequent halts while the passengers rest is illogical. The result, they say, is that the Indian air mail moves at an average speed of no more than 28 miles an hour; for two-thirds of the journey it is stationary while passengers eat pd sleep. On the other hand, experts point triumphantly to the United States lines which, begun as “mails only” enterprises are now rapidly turning ever to the operation of aircraft carrying passengers and mails together. But there can be no doubt about the immense speeding up that would follow the establishment of “mails only” services throughout the Empire, and this is work that the Avro “Mail-plane” Tpye 627 is admirably fitted to do.

THREE MILES A MINUTE. B Last week the new machine completed official trials at Martleshain Heath, the Royal Air Force experi- | mental station where all new British ! aircraft are put through exacting tests. It recorded there a maximum speed, with 8701 b of mails on board and a full t load of fuel sufficient for 6000 miles 1 non-stop, of more than 170 miles an 1 hour, a rat© of climb at ground level of no less than 1200 feet a minute t and a cruising speed ,at only two-thirds ' of full engine power of 140 miles per f ..hour. These figures represent a degree f of performance striking enough to b commend the plan© to aircraft oper--1 ating companies abroad, and within the next fortnight or so the machine ’ ' will be stopped to Canada for further demonstration; actually the conditions 3 governing mail carriage in Canada re- .. ceived prime consideration in working c out the design. > I The Type 627 is a shapely biplane, a 5 wing system chosen by the makers to 1 secure conveniently small overall dimenI sions and low cost of transporting spare 1 wings in emergency. 111 every detail i, is perceptible the insistence in lessen--1 ing resistance to movement through the [ air—the reduction of “drag,” to use the technical term—which is so marked l a feature of present-day British aircraft design. Nothing is here to disturb the flow of air over the structure; even the landing wheels have streamlined casings, while every strut and wire is streamlined. i ; ALL-METAL. Except for the fabric coverings of wings and tail.unit and the fuselage fairings, the entire machine is built of metal, welded steel tubing making up the fuselage framewirk, high tensile I corrugated steel strip, the wings spars and duralumin pressing the wing ribs. The engine, an Armstrong Siddeley “Juguar Major” 525 h.p... air-cooled radial unit, is suirroiunded by a resis- | tance-reducing Townend ring, the outj lines of which merge smoothily into a stream-line exhaust manifold behind the motor, and continue into the fuselage. The single pilot sits in a cockpit immediately aft of the fireproof and water-tight mails compartment, which has a total capacity of 40 cubic feet. His eyes are on a level with the upper wings, and he has a magnificent view in every direction. Seat height and j the position of the rudder bar at his feet are adjustable in flight; before him on the dashboard is an unusually large equipment of navigational apparatus to guide him by day and by night. After dark a flood lighting device illuminates the dash and retractable landing lights are ready for instant use. To meet the rigours of flying in temparatures far below zero the cock, pit is warmed from the engine by a long muff wrapped round a pipe at- • taclied to the exhaust manifold.