Word: ramjet
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Lift from a Plane. Because the basic ramjet is just about the simplest power plant ever to be airborne, its promise has always excited aeronautical engineers. Unlike the conventional jet, it has neither a complex turbine nor a compressor; it is an open-ended cylinder, known as a "flying stovepipe," with only fuel injection and ignition systems inside...
Theoretically, an old-fashioned ramjet can fly through the atmosphere at almost unlimited velocities, but its top speed is limited to about 4,000 m.p.h. by practical considerations. The jet flame, burning conventional fuels, tends to blow out at supersonic flight speeds (above 720 m.p.h. at low altitudes). If it is to keep burning and providing thrust, the ramjet needs an inlet shape to generate its own shock wave, which will slow passage of air through the combustion chamber to a subsonic flow. Above 4,000 m.p.h., however such an inlet design could cause excessive temperatures and pressures...
Hydrogen Cooling. These apparent limitations dampened interest in further ramjet development work until late last year, when Marquardt Corp. scientists convincingly demonstrated a practical method of maintaining combustion in a supersonic flow of air. Using hydrogen, which has a low ignition temperature, burns rapidly and provides high thrust, they kept an experimental scramjet burning in air moving as fast as 7,000 m.p.h. By redesigning their engine's inlet to allow it to gulp air at supersonic speeds, they were also able to eliminate the excessive temperatures and pressures. And they proved that useful thrust could be produced...
...Electrical & Engineering Co., which supplies nonscientist help, has jumped to 1,600 from 878 in 1960. Total employment at the site is now about 2,500. On the great barren area (40 miles by 30 miles), the AEC is testing a nuclear rocket engine, Project Rover, and a nuclear ramjet, Project Pluto (so far non-explosively), is also using chemical explosives to make studies of craters. Since most nuclear authorities agree that any further bomb testing will be done underground to avoid contaminating the atmosphere or the ocean, a force of hard-rock miners is busily digging tunnels into...
...Force v. Navy. The Air Force still sees great promise in high-energy fuels for rockets and ramjet engines, intends to continue working on them at two small pilot plants. But the Navy has decided to abandon its work in the field entirely, convinced that boron fuels do not hold the great promise it expected...