§ Captain Pluggeasked the Under-Secretary of State for Air whether any decision has yet been reached as to whether de-icing apparatus, or anti-ice apparatus, offers better safeguards against the possibility of accidents to aeroplanes caused by ice-forming conditions in the air; and whether he will issue a statement as to the present position with a view to allaying any anxiety being caused by the publicity recently given to this matter?
§ Lieut.-Colonel MuirheadThe present position regarding de-icing and anti-icing is as follows: The chief parts of an aircraft which require, in certain circumstances, protection against icing troubles are the carburettors, instruments, fuel and oil tank vents, wings and control surfaces, airscrews and controls. A Notice to Aircraft Owners was issued last September making compulsory the fitment of anti-icing devices in respect of carburettors, instruments and fuel and oil tank vents. As regards the wings, control surfaces and airscrews, existing knowledge is insufficient to justify making it compulsory to fit any specific device, whether de-icing or anti-icing. As regards the controls, a Notice to Airmen has been issued warning pilots of the possibility of controls becoming jammed and mentioning a particular case of this trouble, together with methods employed in overcoming it.