Unsuccessful attempts to obtain active service in the 1914-18 War led, in 1917, to my first serious job in aviation, in the D.O. at Handley Page, on the 0/400 and V 1500 bombers. As an eyewitness of the spectacular crash of the V prototype—just before my own first flight, on an 0400—I was sharply faced with the first essentials of air safety. Over the next 20 years, on design, strength, performance and stability investigations, flight-testing, etc. of many types of landplanes, flying-boats, autogyros and aero engines, where attainment of acceptable performance was the primary aim, the needs of safety were always much in my mind. Close involvement in various air accidents, near-drowning, frostbite, immersion in a glacial lake, mountaineering, etc., formed a valuable background to subsequent work on survival.