RocketMotorTwo

RocketMotorTwo
Country of originUnited States
DesignerSierra Nevada Corporation
ManufacturerVirgin Galactic
PredecessorRocketMotorOne
StatusActive
Hybrid engine
PropellantNitrous oxide / Hydroxyl-terminated polybutadiene
Performance
Thrust310kN
Specific impulse250 s (2.5 km/s)
Burn time60 seconds
Used in
SpaceShipTwo

RocketMotorTwo (RM2)[1] is a family of hybrid rocket engines developed for the Scaled Composites SpaceShipTwo suborbital spaceplane.

The first-generation engine was developed by Sierra Nevada Corporation (SNC),[2] from the late 2000s to May 2014. It was first ignited in flight during a SpaceShipTwo test launch in April 2013.[3][4] This engine design was subsequently flown in only two additional flight tests during 2013 and January 2014.[5] SNC was a subcontractor to Scaled Composites through May 2014 when their involvement in the program ended after Virgin Galactic elected to replace SNC's version of RocketMotorTwo powered by HTPB rubber fuel, with its own internally developed hybrid motor for SpaceShipTwo.[5]

The second-generation RocketMotorTwo engine is a variant of the earlier SNC basic design. It experimented with using a polyamide plastic fuel and nitrous oxide oxidizer in 2014,[6] but switched back to using its original hydroxyl-terminated polybutadiene (HTPB) fuel and liquid nitrous oxide oxidizer in 2015.[7] The second-generation engine is now made in-house by Virgin Galactic rather than by SNC.

  1. ^ Rob Coppinger (2009). "Virgin Galactic's SpaceShipTwo has rocket motor test success". Flight International. FlightGlobal.
  2. ^ Leonard David. "Virgin Galactic Pushes Private Spaceship Envelope in Test Flights". Space.com. 10 June 2011. Retrieved 19 May 2013.
  3. ^ Cite error: The named reference EnginesIgnited was invoked but never defined (see the help page).
  4. ^ Cite error: The named reference pa20130429sn was invoked but never defined (see the help page).
  5. ^ a b Cite error: The named reference sncpr20141031 was invoked but never defined (see the help page).
  6. ^ Doug Messier (24 May 2014). "Virgin Galactic Hails RocketMotorTwo Milestone". ParabolicArc.
  7. ^ Jeff Foust (14 Oct 2015). "SpaceShipTwo Bounces Back to Rubber Fuel". SpaceNews.