Military

X-59 Quiet Supersonic Technology (QueSST)
Low-Boom Flight Demonstration (LBFD)

NASA’s new experimental aircraft, designed with quiet supersonic technology and intended to help open a new era in faster-than-sound air travel over land, will forever be known in the history books as the X-59 QueSST. The X-59 is shaped to reduce the loudness of a sonic boom reaching the ground to that of a gentle thump, if it is heard at all. It will be flown above select U.S. communities to generate data from sensors and people on the ground in order to gauge public perception. That data will help regulators establish new rules to enable commercial supersonic air travel over land. The U.S. Air Force, which is the government entity responsible for assigning X-number designations and the popular name associated with the aircraft, officially informed NASA of their decision on 26 June 2018. “For everyone working on this important project, this is great news and we’re thrilled with the designation,” said Jaiwon Shin, NASA’s associate administrator for aeronautics.

Since the introduction of the legendary X-1 in 1946, scientists have used the X-plane designations to identify experimental aircraft and rockets used to explore new aerospace technologies. As of early 2016, the X-57 designator appeared to remain un-assigned. The assignment of this designator to this aircraft is conjectural.

In 2016 NASA announced a 10-year plan by NASA Aeronautics to achieve ambitious goals in reducing fuel use, emissions, and noise by the way aircraft are designed, and the way they operate in the air and on the ground. One exciting piece of this 10-year plan is New Aviation Horizons – an ambitious undertaking by NASA to design, build and fly a variety of flight demonstration vehicles, or “X-planes.” The New Aviation Horizons X-planes would typically be about half-scale of a production aircraft, although some may be smaller or larger, and are likely to be piloted. Design-and-build would take several years, with vehicles going to flight starting around 2020 depending on funding.

One X-plane would be a business-jet-sized supersonic vehicle that burns low carbon bio-fuels and generates such quiet sonic booms that people on the ground would barely hear them.

The return of supersonic passenger air travel is one step closer to reality with NASA's award of a contract for the preliminary design of a “low boom” flight demonstration aircraft. This is the first in a series of ‘X-planes’ in NASA's New Aviation Horizons initiative, introduced in the agency’s Fiscal Year 2017 budget. NASA Administrator Charles Bolden announced the award at an event 29 February 2016 [Leap Day] at Ronald Reagan Washington National Airport in Arlington, Virginia.

“NASA is working hard to make flight greener, safer and quieter – all while developing aircraft that travel faster, and building an aviation system that operates more efficiently,” said Bolden. “To that end, it’s worth noting that it's been almost 70 years since Chuck Yeager broke the sound barrier in the Bell X-1 as part of our predecessor agency's high speed research. Now we’re continuing that supersonic X-plane legacy with this preliminary design award for a quieter supersonic jet with an aim toward passenger flight."

NASA selected a team led by Lockheed Martin Aeronautics Company of Palmdale, California, to complete a preliminary design for Quiet Supersonic Technology (QueSST). The work would be conducted under a task order against the Basic and Applied Aerospace Research and Technology (BAART) contract at NASA's Langley Research Center in Hampton, Virginia.

After conducting feasibility studies and working to better understand acceptable sound levels across the country, NASA's Commercial Supersonic Technology Project asked industry teams to submit design concepts for a piloted test aircraft that can fly at supersonic speeds, creating a supersonic "heartbeat" -- a soft thump rather than the disruptive boom currently associated with supersonic flight.

“Developing, building and flight testing a quiet supersonic X-plane is the next logical step in our path to enabling the industry's decision to open supersonic travel for the flying public," said Jaiwon Shin, associate administrator for NASA’s Aeronautics Research Mission.

Lockheed Martin received about $20 million over 17 months for QueSST preliminary design work. The Lockheed Martin team included subcontractors GE Aviation of Cincinnati and Tri Models Inc. of Huntington Beach, California.

The company developed baseline aircraft requirements and a preliminary aircraft design, with specifications, and provided supporting documentation for concept formulation and planning. This documentation would be used to prepare for the detailed design, building and testing of the QueSST jet. Performance of this preliminary design also must undergo analytical and wind tunnel validation.

In addition to design and building, this Low Boom Flight Demonstration (LBFD) phase of the project also included validation of community response to the new, quieter supersonic design. The detailed design and building of the QueSST aircraft, conducted under the NASA Aeronautics Research Mission Directorate's Integrated Aviation Systems Program, would fall under a future contract competition.

A task order was awarded for preliminary design of a Quiet SuperSonic Technology (QueSST) aircraft concept. An Aircraft System Requirements Review (ASRR) was completed in June 2016 to refine and finalize NASA's mission and aircraft requirements. Maturation and integration of a preliminary QueSST aircraft concept confirmed that the desired mission and aircraft requirements are valid. A Preliminary Design Review (PDR) of this aircraft concept would be completed in June 2017. The resulting requirements and design approaches may be leveraged for the detailed design phase.

NASA Armstrong Flight Research Center planned to issue a Request for Proposal (RFP) for Low-Boom Flight Demonstration (LBFD) in mid-2017. NASA's Aeronautics Research Mission Directorate (ARMD) strategy is guided by six strategic thrusts identified in response to three overarching global mega-drivers that will, in large part, shape the needs of aeronautical research in the coming years. These drivers and thrusts are described in the ARMD Strategic Implementation Plan (SIP). In the near term (2015-2025), Strategic Thrust 2, Innovation in Commercial Supersonic Aircraft, outlines the ARMD objective of enabling the establishment of a standard for acceptable overland supersonic flight, in cooperation with international standards organizations. ARMD would develop and validate analysis tools and technologies intended to enable the design and development of supersonic aircraft with low sonic boom. In the longer term (2025-2035), ARMD would continue research on technologies required to meet the desired boom level in larger aircraft, but would also conduct research in areas related to other challenges to successful supersonic transports.

Under NASA ARMD's Advanced Air Vehicles Program (AAVP), the Commercial Supersonic Technology (CST) Project provides the research and leadership to achieve ARMD's objectives in Strategic Thrust 2. ARMD has formed Research Themes that support the desired outcomes for this strategic thrust (see the ARMD SIP link above). Within these Research Themes, the CST Project focused a majority of its research on certain key Technical Challenges that were viewed as enabling to the Strategic Thrust 2 near-term outcomes. The current Technical Challenges were: 1) Integrated Low Boom Aircraft Design, 2) Sonic Boom Community Response Metric and Methodologies, and 3) Low-Noise Propulsion for Low-Boom Aircraft. Concurrently, the CST Project also conducts research in other key areas related to successful supersonic transports, such as improvements in supersonic cruise efficiency, reduced emissions, aero-servo-elasticity, and flight systems.

Based on research over the past few years, NASA determined that the best approach to accomplish the goals of the Thrust 2 near-term objective and the first two CST Project Technical Challenges was to conduct a flight demonstration. To that end, the CST Project conducted concept feasibility studies and project planning for a Low-Boom Flight Demonstration (LBFD) aircraft that would provide validation of design tools and technologies applicable to low sonic boom aircraft and create a database of community response supporting the development of a noise-based standard for supersonic overland flight.

NASA refined a set of LBFD aircraft capabilities required to conduct effective community response studies. NASA's objectives would be accomplished through the design, construction, and flight validation of a sub-scale research aircraft that creates a shaped sonic boom signature with a calculated loudness level of 75 PLdB [Perceived Level (PL), decibels (dB)] or less during supersonic cruise (Mach = 1.4) flight. Although the aircraft would be smaller in size than future supersonic airliners, its sonic boom ground signature would be traceable to that of the larger aircraft. The LBFD aircraft would be capable of performing multiple supersonic overflights of a single community with passes that are nominally 50 miles in length, and 20 minutes apart on a single flight.

Under NASA ARMD's Integrated Aviation Systems Program (IASP), the LBFD Project would be executed in two distinct phases, with a third phase envisioned as a follow-on activity. Phase 1 includes the LBFD aircraft development activities from detailed design through fabrication, concluding with functional checkouts and supersonic envelope expansion.

In Phase 2, a NASA-led team would perform low-boom acoustic validation flights of the LBFD aircraft. These flights would be conducted from NASA's Armstrong Flight Research Center (AFRC) and characterize and evaluate the near-field, mid-field, far-field, and ground signatures from the LBFD aircraft. This characterization would include the effects of changing atmospheric and aircraft flight conditions.

Phase 2 would conclude with an initial community response overflight study involving communities near AFRC. The purposes of this study would be validation of the community test designs developed by the CST Project and an initial exploration of community acceptance of low-boom noise.For the Phase 3 follow-on, a NASA-led team would conduct low-boom community response overflight studies with multiple test campaigns using the LBFD aircraft over varied locations. Studies may include multiple deployments over a 2-year period to capture a representative spectrum of communities, geography, and meteorological conditions across the United States. The primary data from these studies would be community response, with limited collection of aircraft, ground, and meteorological data.

The ultimate goal of Phase 3 would be to develop a low-boom community response database that would be provided to the Federal Aviation Administration (FAA) and International Civil Aviation Organization (ICAO) Committee on Aviation Environmental Protection (CAEP) in support of their development of a noise-based standard for supersonic overland flight.

NASA planned to select a Vehicle Contractor for the Phase 1 detailed design, build, test, and then delivery of the LBFD aircraft system that would be flown in Phases 2 and 3. NASA would retain oversight of the airworthiness certification and anticipates being a significant participant in Phase 1 activities. NASA would provide support that would include in-flight and ground systems, instrumentation and operations, simulation, wind-tunnel testing, and safety and mission assurance. NASA would also supply aircraft components and systems as Government Furnished Equipment (GFE) whenever feasible, and considered to add value to the development of the LBFD aircraft. NASA envisions significant opportunities for collaboration with industry and academia, both domestic and international, during Phase 2 and 3 activities.

NASA anticipated issuing a performance-based Request for Proposal for the design, build, and test of the LBFD aircraft, as described in Phase 1, with potential for a second aircraft. The procurement would be a requirements-driven approach, as opposed to build to print, and the maturity of the proposed concept was expected to be consistent with a PDR level of development. The Government does not intend to acquire a commercial item using FAR Part 12. This would be an unrestricted procurement (full and open competition). The North American Industry Classification System (NAICS) code for this procurement was 336411 - Aircraft Manufacturing, with a small business size standard of 1,500 employees.

In accordance with Federal Acquisition Regulation (FAR) 9.104-1, FAR 9.104-2, and FAR 9.105(b)(1), NASA intended to conduct a pre-RFP release Responsibility Determination. NASA may use the list of responsible vendors to facilitate a pre-solicitation release of more detailed requirements, design data, and specifications that have resulted from the preliminary design activity.

NASA’s first large scale, piloted X-plane in more than three decades is cleared for final assembly and integration of its systems following a major project review by senior managers held 16 December 2019 at NASA Headquarters in Washington. The management review, known as Key Decision Point-D (KDP-D), was the last programmatic hurdle for the X-59 Quiet SuperSonic Technology (QueSST) aircraft to clear before officials meet again in late 2020 to approve the airplane’s first flight in 2021. “With the completion of KDP-D we’ve shown the project is on schedule, it’s well planned and on track. We have everything in place to continue this historic research mission for the nation’s air-traveling public,” said Bob Pearce, NASA’s associate administrator for Aeronautics.

Construction of the X-59, under a $247.5 million cost-plus-incentive-fee contract, continued at Lockheed Martin Aeronautics Company’s Skunk Works factory in Palmdale, California. Three major work areas are actively set up for building the airplane’s main fuselage, wing and empennage. Final assembly and integration of the airplane’s systems – including an innovative cockpit eXternal Visibility System – is targeted for late 2020.