When U.S. rocket engineers talk about the bright possibilities of solid-fuel rockets, they always have to pause over one big requirement: how to control the fuel's burning rate. A current system is to shape the charge, measure the ingredients—and hope. This week Acoustica Associates, Inc. of Plainview, N.Y. announced an initial $85,188 contract with the National Aeronautics and Space Administration to explore a radical new control that is as exciting as it is simple. The company thinks that it can handle solid fuels by filling the rocket with sound—plain, ordinary noise.
Acoustica engineers...