The Northrop M2-F3 is a heavyweight lifting body rebuilt from the Northrop M2-F2 after it crashed at the Dryden Flight Research Center in 1967. It was modified with an additional third vertical fin—centered between the tip fins—to improve control characteristics. The "M" refers to "manned" and "F" refers to "flight" version.

Development Early flight testing of the M2-F1 and M2-F2 lifting body reentry configurations had validated the concept of piloted lifting body reentry from space. When the M2-F2 crashed on May 10, 1967, valuable information had already been obtained and was contributing to new designs.

NASA pilots said the M2-F2 had lateral control problems, so when the M2-F2 was rebuilt at Northrop and redesignated the M2-F3, it was modified with an additional third vertical fin—centered between the tip fins—to improve control characteristics.

After a three-year-long redesign and rebuilding effort, the M2-F3 was ready to fly. The May 1967 crash of the M2-F2 had torn off the left fin and landing gear. It had also damaged the external skin and internal structure. Flight Research Center engineers worked with Ames Research Center and the Air Force in redesigning the vehicle with a center fin to provide greater stability. At first, it seemed that the vehicle had been irreparably damaged, but the original manufacturer, Northrop, did the repair work and returned the redesigned M2-F3 with a center fin for stability to the FRC.

While the M2-F3 was still demanding to fly, the center fin eliminated the high risk of pilot-induced oscillation (PIO) that was characteristic of the M2-F2.

Operational history The first flight of the M2-F3, with NASA pilot Bill Dana at the controls, was June 2, 1970. The modified vehicle exhibited much better lateral stability and control characteristics than before, and only three glide flights were necessary before the first powered flight on November 25, 1970. The 100th flight of the heavy-weight lifting bodies was completed on October 5, 1972, with pilot Bill Dana soaring to an altitude of 66,300 feet (20,200 m) and a Mach number of 1.370 (about ) in the M2-F3. Over its 27 missions, the M2-F3 reached a top speed of (Mach 1.6). The highest altitude reached by the vehicle was 71,500 feet (20,790 m) during its last flight on December 20, 1972, with NASA pilot John A. Manke at the controls.

A reaction control thruster (RCT) system, similar to that on orbiting spacecraft, was also installed to obtain research data about their effectiveness for vehicle control. As the M2-F3's portion of the lifting body program neared an end, it evaluated a rate command augmentation control system, and a side control stick similar to side-stick controllers now used on many modern aircraft.

NASA donated the M2-F3 vehicle to the Smithsonian Institution in December 1973. It is currently on display in the Steven F. Udvar-Hazy Center, outside the James S. McDonnell Space Hangar where the Space Shuttle Discovery is housed.

M2-F3 pilots William H. Dana: 19 flights John A. Manke: 4 flights Cecil W. Powell: 3 flights Jerauld R. Gentry: 1 flight

Aircraft serial number NASA M2-F3: NASA 803, 27 flights

M2-F3 flights VehicleFlight # Date Pilot Mach Velocity(km/h) Altitude DurationComments ft m M2-F3 #1 June 2, 1970 Dana 0.688 755 00:03:38 First M2-F3 FlightUnpowered glide M2-F3 #2 July 21, 1970 Dana 0.660 708 00:03:48 Unpowered glide M2-F3 #3 November 2, 1970 Dana 0.630 690 00:03:56 Unpowered glide M2-F3 #4 November 25, 1970 Dana 0.809 859 00:06:17 1st powered flight M2-F3 #5 February 9, 1971 Gentry 0.707 755 00:04:01 - M2-F3 #6 February 26, 1971 Dana 0.773 821 00:05:48 Only 2 chambers lit M2-F3 #7 July 23, 1971 Dana 0.930 988 00:05:53 - M2-F3 #8 August 9, 1971 Dana 0.974 1,035 00:06:55 - M2-F3 #9 August 25, 1971 Dana 1.095 1,164 00:06:30 1st supersonic flight M2-F3 #10 September 24, 1971 Dana 0.728 772 00:03:30 Engine fire M2-F3 #11 November 15, 1971 Dana 0.739 784 00:03:35 - M2-F3 #12 December 1, 1971 Dana 1.274 1,357 00:06:31 - M2-F3 #13 December 16, 1971 Dana 0.811 861 00:07:31 Only 2 chambers lit M2-F3 #14 July 25, 1972 Dana 0.989 1,049 00:07:00 - M2-F3 #15 August 11, 1972 Gentry 1.101 1,168 00:06:15 - M2-F3 #16 August 24, 1972 Dana 1.266 1,344 00:06:16 - M2-F3 #17 September 12, 1972 Dana 0.880 935 00:06:27 Small engine fire M2-F3 #18 September 27, 1972 Dana 1.340 1,424 00:06:07 - M2-F3 #19 October 5, 1972 Dana 1.370 1,455 00:06:16 100th liftingbody flight M2-F3 #20 October 19, 1972 Manke 0.905 961 00:05:59 - M2-F3 #21 November 1, 1972 Manke 1.213 1,292 00:06:18 - M2-F3 #22 November 9, 1972 Powell 0.906 961 00:06:04 - M2-F3 #23 November 21, 1972 Manke 1.435 1,524 00:06:17 Planned RosamondLakebed landing M2-F3 #24 November 29, 1972 Powell 1.348 1,432 00:05:57 - M2-F3 #25 December 6, 1972 Powell 1.191 1,265 00:05:32 Planned RosamondLakebed landing M2-F3 #26 December 13, 1972 Dana 1.613 1,712 00:06:23 Fastest flight M2-F3 #27 December 20, 1972 Manke 1.294 1,378 00:06:30 Highest flightLast M2-F3 flight

Specifications (M2-F3)

Gallery

See also Comparable aircraft: X-24 M2-F1 M2-F2 HL-10

References https://web.archive.org/web/20090413053930/http://www.dfrc.nasa.gov/Gallery/Photo/M2-F3/HTML/index.html https://web.archive.org/web/20030202015833/http://www.dfrc.nasa.gov/Newsroom/FactSheets/FS-011-DFRC.html https://aletro.org/learning_project_files/LBBOOK_updated_contacts.pdf

External links

NASA Dryden M2-F3 Photo Collection Wingless Flight: The Lifting Body Story. NASA History Series SP-4220 1997 PDF