Monthly Archives: April 2020
Excerpt from November 27, 1944 Life magazine
Jet Propulsion Launches a New Era in Man's Locomotion
You have to look twice at the airplane pictured above to see that it is flying without a propeller. Its motive force is the thrust of two invisible streams of hot combustion gases, jetted at high velocity from its engines. This plane is the Army Air Forces' P-59, the first U.S. plane to be flown by jet propulsion, Like the first horseless carriage, the propellerless P-59 does not suggest by its appearance that a new age in locomotion is at hand. The fact is, however, that the aerodynamic lid is off. With jet propulsion, aircraft have already climbed to new speeds and altitudes. The ultimate ceiling is as high as man's daring and ingenuity will take it. The principle of jet propulsion, demonstrated on the next two pages, is Newton's third law of motion: to every action there is opposed a reaction which is equal in force and opposite in direction. Anyone who has fired a rifle knows this reaction as the recoil that kicks the butt against the shoulder. A jet plano similarly recoils from the thrust of its jet. Jet Propulsion is the same force that propels a rocket. For the moment, however, a distinction has been drawn between rocket propulsion and jet propulsion in order to minimize confusion between the rocket and a new class of air-breathing jet propulsion engines. The rocket does not breathe air. It carries its own supply of oxygen with it. A rocket may thus conceivably travel outside earth's atmosphere. The reported 60-to 70-mile climb of the Nazi's V-2 rocket is miles beyond the ceiling of air-breathing jet engines. Two air-breathing jet engines are now in operation. One is the ingenious "reaction pipe" that drives the German flying bomb. The other, and by far the more important, is the gas turbine. This is the engine that powers the P-29 and has tied the main stream of aviation progress to jet propulsion. As shown on page 52, this ei ing part, its rotor, and operates with the utmost simplicity. It inhales air in huge quantities, compresses it and brings it to high temperature by combustion. Resulting hot gases spin the turbine which spins the compressor. Then, still hot and under pressure, the pipe. This pipe is the jet engine's "propeller."