Supersonic business aviation took a step closer to reality this week after NASA began flight testing Gulfstream’s patented Quiet Spike sonic-boom mitigation device on a Boeing F-15.
The Quiet Spike is designed as part the design for Gulfstream's proposed Supersonic Business Jet (SSBJ), which also features wings that sweep back and centreline engines (see animation below). On an operational SSBJ, Quiet Spike will probably have four sections. It has yet to be determined whether a tail spike is needed to deal with the aft sonic shock.
|The Gulfstream SSBJ will transform from subsonic configuration to supersonic configuration|
A second aircraft will probe the supersonic signature in the near field, to see if the wave system is as predicted. The Quiet Spike is designed to divide the bow shock into several less-intense pressure waves, turning the characteristic N-wave sonic boom into a softer S-shaped signature.