Authentic Science Fiction Monthly, No. 56 — page 58: what you’re looking at

Machine-transcribed from the original scan — historical spelling and the odd misread are preserved.

AUTHENTIC SCIENCE FICTION AIR The reciprocating internal combustion engine which has served heavier than air flying since its beginning is now on its way out and within fifty years of its large-scale applica- tion to aviation it may be the exception rather than the rule. It has certain advantages for light planes which may result in its retention for a period, but the commercial and mili- tary aircraft of the future will be propelled by “‘jet”’ engines of various types. The older internal combustion en- gine is reaching the limits of its theoretical maximum power, and jet propulsion erijoys certain other advan- tages which make it certain as the motive power of the future. There is a smaller number of moving parts, reduced vibration, safer fuel, the possibility of great power for weight, better streamlining and, above all, ability to fly in the stratosphere where the air is too “thin” for the ordinary airscrew. The ad- vantage of very high altitude flights is, of course, that air resistance is reduced to a point where it is so low that enormous speeds are easy to attain. In the immediate future 57 there will be a considerable field for the prop-jet engine in which the fuel is burned as in the normal jet engine, but the driving force is obtained, not from jet reaction, but by gearing a turbine to propellers. Within ten years at least 500 m.p.h. should be the accepted average speed for commercial aviation using the turbo-jet engine. By that time considerable progress should have been made with the ram- jet engine, which operates efficiently at higher speeds and which will eventually carry aircraft at well over 2,000 m.p.h. at high altitudes. True rocket propulsion will call for flights at a height of at least 100,000 ft. and will give us speeds of 5,000 m.p.h. and upwards, with a present theoretical limit of about 18,000 m.p.h. for journeys near the earth, and 25,000 m.p.h. for journeys in space. This would make possible the realisation of the ideal which has been suggested of an air service, “anywhere in an hour on the hour,” but it would be optimistic to sug- gest that the great problems involved will be solved in less than fifty years. A much more immediate concern of aviation is the comicloooks.com