Initiated during 2008, the X-54 project is intended to produce an experimental aircraft capable of supersonic speeds with a formed sonic boom that is acoustically shaped to mitigate noise pollution. The X-54A is intended to produce demonstrate low-boom sonic effects in population impact studies in support of future supersonic transport design and regulation. Current regulations prohibit supersonic flight over land areas in the United States; the X-54 is part of NASA's efforts to have the regulations altered to allow for supersonic transports to be commercially viable.
NASA's X-54 project is intended to continue the research objectives of the DARPA Quiet Supersonic Aircraft, and is intended to demonstrate low-boom technologies and methods validated by projects such as the NASA Quietspike project, the Shaped Sonic Boom Demonstrator, FaINT Project, and WSPR Project. The X-54 will be designed from the ground up to incorporate all the technology and lessons learned from this combined NASA research spanning several decades into a viable aircraft capable of producing under 75 pdB on the ground while cruising over Mach 1.4 above 50,000 feet. The X-54 aircraft will demonstrate low-noise supersonic flight for use in community base testing to provide research data to reform domestic and international regulations on supersonic over-land flight.
The X-54A was reported as being developed by Gulfstream Aerospace and is intended to be powered by two Rolls-Royce Tayturbofan engines. The X-54A may be connected to Gulfstream's "Sonic Whisper" program, trademarked in 2005 as an aircraft design to "reduce boom intensities during supersonic flight;" besides Gulfstream, Lockheed Martin and Boeing have also produced viable designs for commercial supersonic aircraft and all three companies are thought to be contenders in a competition for the X-54 demonstrator aircraft, however as of 2012 NASA lacked the funds to progress the project.
Although Gulfstream has made little comment about the X-54A project, at the 2008 National Business Aviation Association convention a Gulfstream executive stated that Gulfstream's work on advanced technologies for supersonic flight had been ongoing "for some time" and that a "complete airplane designed for low [sonic] boom" would possibly "have X-54 painted on the side of it."
As of late 2012 there were indications that Gulfstream was close to announcing the design of a quiet supersonic business jet, first drawings of which appeared in December 2012.