SpaceX Kestrel

SpaceX Kestrel
SpaceX Kestrel
Country of originUnited States
First flight2006
Last flight2009
DesignerTom Mueller
ManufacturerSpaceX
ApplicationUpper stage boost
Liquid-fuel engine
PropellantLOX / RP-1
CyclePressure fed
Performance
Thrust, vacuum28 kN (2.9 tf)
Thrust-to-weight ratio65
Chamber pressure9.3 bar (135 psi)
Specific impulse, vacuum317 seconds (3.11 km/s)
Dimensions
Dry mass52 kg (115 lb)
References
References[1][2][3]
Kestrel engine test firing.

The SpaceX Kestrel was an LOX/RP-1 pressure-fed rocket engine. The Kestrel engine was developed in the 2000s by SpaceX for upper stage use on the Falcon 1 rocket. Kestrel is no longer being manufactured; the last flight of Falcon 1 was in 2009.

Kestrel was built around the same pintle architecture as the SpaceX Merlin engine but does not have a turbopump and is fed only by tank pressure.

Kestrel was ablatively cooled in the chamber and throat and radiatively cooled in the nozzle, which was fabricated from a high strength niobium alloy. As a metal, niobium is highly resistant to cracking compared to carbon-carbon. According to SpaceX, an impact from orbital debris or during stage separation might dent the metal but have no meaningful effect on engine performance.[4] Helium pressurant efficiency is substantially increased via a titanium heat exchanger on the ablative/niobium boundary.[5]

Thrust vector control is provided by electro-mechanical actuators on the engine dome for pitch and yaw. Roll control (and attitude control during coast phases) is provided by helium cold gas thrusters.

A TEA-TEB pyrophoric ignition system is used to provide restart capability on the upper stage and simplify design.[6] In a multi-manifested mission, this design would allow for drop off at different altitudes and inclinations.

  1. ^ "Falcon 1 Users Guide" (PDF). SpaceX. 2008-09-28. Archived from the original (PDF) on October 1, 2008.
  2. ^ spachelaunchreport.com - falcon
  3. ^ astronautix Archived 2013-12-16 at the Wayback Machine
  4. ^ Greg Zsidisin (23 March 2007). "SpaceX Confirms Stage Bump On Demoflight 2". Space Daily. Retrieved 2008-09-30.
  5. ^ "Falcon 1 Flight Three Press Kit" (PDF). SpaceX. Archived from the original (PDF) on 2008-10-01. Retrieved 2008-09-30.
  6. ^ "Space Exploration Technologies Corporation - Updates Archive". SpaceX. Archived from the original on 2007-11-05. Retrieved 2024-09-13.