Recent Technical Developments: A Hand Air‐Compressor—New “Brico” Foundries—The Air‐Cooled Engine Defended—The Cyanide Process

AN AIR‐COMPRESSOR FOR STARTING The difficulties and uncertainties encountered in starting the average aero‐engine by direct cranking are too well‐known to need elaboration. The trend towards high powers and the inaccessibility of some engines adds to these difficulties. Starting by means of compressed carburetted air is a great advance over the earlier method, and the use of a motor‐driven air compressor (ground equipment) makes engine starting the certainty it should be. This essential ground equipment is not always available in the case of forced landings, and, in any case, it is advisable to have the aircraft so equipped that it is independent of outside aid, provided this can be done for a reasonable addition of weight.