Lockheed L-301
| L-301 | |
|---|---|
| |
| X-24C configuration images circa January 1977 | |
| Role | Hypersonic research project |
| National origin | United States |
| Manufacturer | Lockheed |
| Status | Cancelled project |
| Number built | None |
Lockheed L-301 (sometimes called the X-24C, though this designation was never officially assigned) was an experimental air-breathing hypersonic aircraft project. It was developed by the NASA and United States Air Force (USAF) organization National Hypersonic Flight Research Facility[1] (NHFRF or NHRF[2]), with Skunk Works as the prime contractor. In January 1977, the program was "tentatively scheduled to operate two vehicles for eight years and to conduct 100 flights per vehicle."[3] NASA discontinued work on L-301 and NHRF in September 1977 due to budget constraints and lack of need.[1]
Development
The L-301 HGV was intended to be a follow-on to the X-15 and X-24 (specifically the X-24B) programs, to take lessons learned from both and integrate them into an airframe capable of at least reaching Mach 8 and engaging in hypersonic skip-glide maneuvers for long range missions. While the NASA program, one of several to use the tentative X-24C designator, was ostensibly canceled in 1977, it was only canceled at the time because of USAF disclosures of duplicate black programs with the same contractors for similar vehicles[citation needed]. The vehicle used both air breathing ram or scramjet propulsion as well as a rocket engine, carrying both RP-1 and LH2 propellant as well as on-board stores of LOX.
Drawings and mission profiles are available from the NASA website.[4]
Design
Propulsion
Originally intended to carry the same XLR-99 engine used by the X-15, the primary engine was changed to the LR-105, which was the sustainer engine used on the Atlas launcher. This rocket engine, burning RP-1 and LOX, was intended to accelerate the X-24C to hypersonic speeds in order to ignite the hydrogen fueled, air breathing ram/scramjet mounted in the belly of the airframe with which it would attain cruise speeds of at least Mach 6 and peak velocities of Mach 8+ at altitudes of 90,000 feet or more. As such, this vehicle was plainly not intended to reach orbit.[citation needed]
Airframe
Design of the aircraft in various wind tunnel models and contractor drawings seems to follow variations of the FDL-5 and FDL-8 lifting body shapes originally developed by the USAF Flight Dynamics Laboratory in the 1950s, which were used in the earlier X-23 and X-24A/B programs. With a radically swept delta wing, and 2, 3, or 4 vertical stabilizers, as well as several body flaps (depending on the model), the vehicle did not lack for control surfaces. The vehicle measured 74 feet 10 inches long, 24 ft, 2 in wingspan, and 20 ft, 7 in height.
Various drawings show a payload bay twelve feet long and perhaps five feet diameter.[5]
References
- ^ a b https://books.google.com/books?id=DUkl5bH6k6EC&pg=PA98&lpg=PA98&dq=National+Hypersonic+Research+Facility+x-15+x-24c&source=bl&ots=Ubvm4kazo1&sig=16Y5rv1y8HLZX8fy8mHZGmDBev4&hl=en&ei=7exrSujtNpLWM4a5tPkG&sa=X&oi=book_result&ct=result&resnum=3 [Lockheed Secret Projects by Dennis R. Jenkins]
- ^ "Archived copy" (PDF). Archived from the original (PDF) on 2009-07-25. Retrieved 2009-07-26.
{{cite web}}: CS1 maint: archived copy as title (link) ["X-24C NHRF"] - ^ https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19790008668_1979008668.pdf [CONFIGURATION DEVELOPMENT STUDY OF THE X-24C HYPERSONIC RESEARCH AIRPLANE - PHASE II]
- ^ https://crgis.ndc.nasa.gov/crgis/images/5/54/PEN00250.pdf
- ^ https://crgis.ndc.nasa.gov/crgis/images/5/5d/PEN00272.pdf
Further reading
- Miller, Jay. The X-Planes: X-1 to X-45. Hinckley, UK: Midland, 2001.
- Rose, Bill, 2008. Secret Projects: Military Space Technology. Hinckley, England: Midland Publishing.
External links
- Operators’ reference drawing [1], [2], [3]
- Encyclopedia Astronautica
- Publicly archived Air Force picture
- Nasa Archives- X-24C Phase 3