Carburettor Air‐Scoops

IN our recent intensive efforts to carry aeroplane performance to higher speeds and altitudes, we have encountered many complex problems in apparently simple development of previously satisfactory practice. Ignition, cooling, and fuel vapour control are only a few instances. Similarly, the design of an aircraft carburettor airscoop would appear to offer only elementary questions of design. How to locate the opening where it will receive full air‐speed ram, and how to fair it in with the cowling structure, would seem to lie well within current knowledge; actually there are indications that many present designs could be improved. Likewise, many of our ideas as to the effect of airscoops upon carburation have been derived from the past when carburettors were non‐automatic, requiring continuous re‐adjustment by the pilot as soon as the aeroplane left the ground for changes of air pressure, temperature, and ram, and any accompanying disturbances in the scoop duct system could usually, though not always, be taken care of by the same manual adjustment.