Stargazer (aircraft)

Stargazer
Stargazer in Northrop Grumman livery, carrying the Pegasus XL for the TacRL-2 mission from Vandenberg Space Force Base in June 2021
General information
TypeLockheed L-1011 TriStar
StatusActive
OwnersOrbital Sciences
Orbital ATK
Northrop Grumman
Construction number193E-1067
RegistrationN140SC[1]
History
First flightFebruary 22, 1974
In service1974–present

Stargazer is a Lockheed L-1011 TriStar built in 1974, that was modified in 1994 for use by Orbital Sciences (now part of Northrop Grumman) as a mother ship for the Pegasus, a small-lift launch vehicle. As of October 2022, 45 rockets (containing nearly 100 satellites) have been launched from Stargazer.[2][3] Stargazer is the only L-1011 airframe still airworthy.[4]

History

The first Pegasus launch to use Stargazer was conducted on 27 June 1994 as the maiden flight of the Pegasus-XL. Previous launches used the NASA-operated Boeing B-52 nicknamed "Balls 8," which was also used for four subsequent launches, as the original Pegasus could not be launched from Stargazer due to clearance issues. A modified version, the Pegasus-H, was introduced to rectify this.

Stargazer was also used for captive tests and transportation of the X-34 hypersonic research aircraft; however, the drop tests used Balls 8.

Stargazer in Orbital Sciences livery launches Pegasus carrying the three Space Technology 5 satellites in 2006

Pegasus launches using Stargazer are usually conducted from Vandenberg Air Force Base. Launches have also been conducted from the Cape Canaveral Air Force Station, NASA's Kennedy Space Center, NASA's Wallops Flight Facility and from launch sites outside the US: Kwajalein Atoll in the Marshall Islands and Gando Airport in Spain.[5]

Orbital Sciences also offer the aircraft for research flights.[6] It is capable of carrying a 23,000 kilograms (51,000 lb) payload to an altitude of 12,800 metres (42,000 ft).[7]

In 2010, Stargazer was reengined with 50,000 lbf (220 kN)-thrust Rolls-Royce RB211-524B4 turbofans to replace its original 42,000 lbf (190 kN)-thrust RB211-22Bs.[8]

Stargazer in Orbital ATK livery, flying over the Atlantic Ocean carrying a Pegasus XL rocket

In 2015, Stargazer was repainted to reflect Orbital Sciences' merger with Alliant Techsystems.[9]

On 15 December 2016, Stargazer successfully launched CYGNSS on behalf of NASA on its second attempt. The first attempt on 12 December was scrubbed due to issues with the hydraulic system responsible for separating the Pegasus rocket from the launch aircraft.[10]

Stargazer appeared in Northrop Grumman livery in 2018 following the acquisition of Orbital ATK.[11] Stargazer launched the Ionospheric Connection Explorer on 11 October 2019. The launch was originally scheduled for June 2017 but was scrubbed when an anomalous piece of vehicle data was observed during a ferry flight. The data was related to the rudder position of the Pegasus XL rocket and was observed during a routine in-flight vehicle health check.[12] The launch was delayed multiple times from 2017 to 2019, finally occurring October 11, 2019.[4]

Background

The Lockheed L-1011 TriStar carrier aircraft first flew in February 1974, and was delivered to Air Canada as C-FTNJ the following month. In May 1992 Orbital Sciences acquired the plane and had Marshall Aerospace in the UK implement accommodations for the Pegasus system. It was renamed for use as carrier aircraft for the Pegasus launch system.[12] The company also considered other aircraft including the Boeing B-52G Stratofortress, Boeing 747, and DC-10, taking into account altitude and speed performance, range, modification complexity, and acquisition and operational costs.[13]

See also

References

  1. ^ "FAA Registry (N140SC)". Federal Aviation Administration.
  2. ^ "Aircraft Registration Database Lookup". www.airframes.org. Archived from the original on 2022-10-26. Retrieved 2022-10-26.
  3. ^ "Pegasus". Northrop Grumman. Archived from the original on 2023-07-26. Retrieved 2022-10-25.
  4. ^ a b Clark, Stephen (10 October 2019). "Rockets purchased by Stratolaunch back under Northrop Grumman control". Spaceflight Now. Archived from the original on 8 December 2019. Retrieved 10 February 2021.
  5. ^ Krebs, Gunter. "Pegasus". Gunter's Space Page. Archived from the original on 2013-08-03. Retrieved 2009-02-20.
  6. ^ ""Stargazer" L-1011 Carrier Aircraft". Orbital Sciences Corporation. Archived from the original on 2014-04-20. Retrieved 2009-02-20.
  7. ^ "L-1011 Fact Sheet" (PDF). Orbital Sciences Corporation. 2014. Archived from the original (PDF) on 2014-04-22. Retrieved 2009-02-20.
  8. ^ Norris, Guy (May 4, 2022). "Riding Along For An L-1011 Air Launch Flight Demonstration". Aviation Week Network. Archived from the original on 2023-03-30. Retrieved 2022-10-27.
  9. ^ Ray, Justin (April 19, 2015). "Photo: New Orbital ATK paint job for Pegasus carrier jet". Spaceflight Now. Spaceflight Now Inc. Archived from the original on 2022-05-18. Retrieved 9 June 2016.
  10. ^ Kremer, Ken (December 13, 2016). "Hydraulic Pump Glitch Aborts NASA's Hurricane MicroSat Fleet Launch to Dec. 15 - Live Coverage". Universe Today. Archived from the original on 2022-01-17.
  11. ^ Granath, Bob (7 November 2018). "Stargazer Aircraft Airborne with Pegasus XL, ICON Satellite". NASA. Archived from the original on 2022-10-26. Retrieved 23 February 2021.
  12. ^ a b Bergin, Chris (August 27, 2018). "ICON resets for October launch from the East Coast". NASA Spaceflight. Archived from the original on 2021-06-23.
  13. ^ Mosier, Marty; Rutkowski, Ed (1993). "Pegasus XL Development and L-1011 Pegasus Carrier Aircraft". Utah State University Libraries. Dulles, VA: Orbital Sciences Corporation. Archived from the original on 2022-09-23.