THE efforts of one manufacturer to solve the problem of jet-engine noise suppression when test facilities are near residential communities are reported here.
The authors describe the construction of several suppressors and give data on their effectiveness.
Their experience covers a run-up suppressor and also a portable unit of the water-injector type-both developed for the B-52 airplane, and a water-spray muffler for ramjet engines.
They emphasize the fact that, since World War II, airplane manufacturers have been required to spend more and more time, effort, and money in attempts to cut down the noise produced by airplane and guided missile powerplants.
The efforts of their company, they point out, are similar to those of other airplane companies. It appears that the problem is growing. No simple solution is yet in sight.