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Wairarapa Times-Age, 10 July 1940, Page 3

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carries on USE IN TASMAN PLANES. RELIEF FROM MONOTONOUS DUTIES. As the Tasman Empire flyingboats drone steadily over the 1200 miles of sea between Australia and New Zealand ■•George” sits placidly at the controls and automatically pilots the huge machines through fair weather and foul. When the Awarua landed on the Waitemata the other morning (says the "Auckland Star”) "George's” foster-father was among the passengers, and he explained the intricacies that have earned for "George" the respect of the Royal Air Force for the past eight years. “George" is the automatic pilot. Mr G. W. Brown is an expert from the Smith Aircraft Instruments Company. of London, and his headquarters have been at Auckland since the inauguration of the Tasman service. He' stated that with the exception of the quarter-hour involved in leaving the water and landing. "George" had been in control of the ship for the entire voyage, leaving the pilot free to take charge of his throttles and navigation instruments. It was explained that the purpose of an automatic pilot is to relieve the pilot from the monotonous duties of active piloting on long flights or under bad weather conditions, and since it is able to control the aircraft with much greater accuracy than the most skilled human pilot, its use is conductive to greater safety and economy. PHYSICAL STRAIN. Provided that a machine is fitted with a suitable equipment of instruments for blind flying, a skilled pilot can fly an aeroplane in almost any weather conditions, but the physical and mental strain of flying in bad conditions, with poor visibility, is considerable. When, in addition, the pilot is faced with the task of navigating the craft to its destination, his task is serious. However, the automatic pilot is not just a gadget intended to relieve the pilot of his normal duties. It is not a mere "blind-flying instrument” adapted to the control of the aircraft, but is a mechanism of the highest reliability and precision. When it is in use there is not the slightest necessity for frequent checking of the course by reference to the magnetic compass. “George” depends for his operation on two gyroscopes driven by compressed air. A gyroscope, which consists of a "flywheel” rotating at high speed in a special form of mounting, possesses the property of tending to maintain its axis fixed in a given direction. A perfectly balanced and freely supported gyroscope spinning at high speed will, in fact, maintain the line of its axis fixed directionally almost indefinitely, no matter how, the mounting may be moved. PRINCIPLE INVOLVED. When a gyroscope is installed in an aircraft, then whatever direction the aircraft may take or however disturbed the weather conditions may be, the axis of the gyroscope will continue to point in the same direction as when it was started. If the aircraft should deviate from its steady course, the angle through which it has turned can be readily ascertained by reference to the gyroscope. Should the aircraft deviate from its course the axis of the gyroscope will no longer lie fore and aft in the machine. and this departure actuates a small air valve, which is so arranged that it causes the aircraft rudder to be applied through the agency of a "servo-motor" in order to correct the deviation. The same gyroscope is used to control the elevators of the aircraft when a pitch disturbance occurs, but a second gyroscope is employed to control the ailerons. As in the case of the rudder control, deviations of the aircraft in pitch and roll operate small air valves which control the movements of the appropriate air controls. SENSITIVE CONTROLS. The sensitivity of these valves is such that a deviation of the aircraft of about a tenth of a degree is sufficient to cause a correcting movement of the appropriate control. The pilots of the Tasman flyingboats are provided with a main control cock for bringing "George” into action, and they are also provided with certain additional controls for executing turns while under automatic control and for varying the pitch altitude. In addition to these controls, a lever is provided by which all three of the servo-motors may be mechanically disconnected from the aircraft controls in an emergency. The cost of an automatic pilot is approximately £lOOO.