HISTORY OF FLIGHT—LOENING 300 
side. To be sure, in close navigation in heavy weather we do need 
to know if another plane is near us, but it is within the power of 
radar instrumentation today to supply aircraft with close-proximity 
radars, possibly even with a television connection that would show up 
anything in the immediate vicinity. Radio, of course, has helped tre- 
mendously to bring about the era of practical civilian flying, and it 
can be counted on to continue to give us the things we need now if we 
will but indicate the required elementary development—simple, close- 
reading radar with 2-mile radius to begin with, not 200 miles—direct- 
reading radio altimeters, with 200 feet radius, not 40,000 feet. We 
have been demanding too much all at once of these instruments, with 
the result that we have little as yet. 
THE JETPLANE DEVELOPMENT 
The jetplanes of the day in America are not being developed in the 
same way as they are in Europe in one particularly important charac- 
teristic—the location of the jet engine. The Douglas DC-8 and Con- 
vair 880 have followed the lead of the Boeing 707, which naturally 
followed the lead of the B-47 and the B-52. Unfortunately, these 
leads seem to derive from the old position of piston engines in nacelles 
mounted outboard on the wings. Here we have a very typical illus- 
tration of a lesson not learned from the history of our art. For a jet 
engine there could not be a more questionable location. Jet engines 
are very light, so that the structural saving of spreading the weight 
over the wing is very much less than in the case of the piston engine. 
Also there is no propeller clearance requirement. But the engines are 
now located so low that they will ingest any loose material on the 
runway with great risk to the delicate turbine engine interiors. 
The outboard engine is so low that a tire or wheel failure on one 
side could break it up on the ground, followed possibly by fire from 
the gas tanks above it. The position of the engine under the wing 
makes the wing a perfect sounding board to disturb the neighbors 
below, and the inboard engine is so located that its noise cone hits the 
rear of the fuselage, making it an almost untenable position. The 
builders and operators are fully aware of these features and are of 
course doing all they can to assure us maximum safety. 
But in Europe, most of the newer commercial designers completely 
separate themselves from all piston-engine concepts by placing the jet 
engines where they belong: above the wing and to the rear, mounted to 
the fuselage and leaving the wing with perfect aerodynamic cleanness. 
Maintenance also is improved by this location. WTOL* concepts 
mentioned below may soften the impact of this questionable American 
design. Let us hope they do. 
% Vertical takeoff and landing. 
