XCOR Lynx: Thrusters!

Engineer Jeremy Voigt tests the Lynx 3N22 Thruster prototype. This thruster has been fired hundreds of times, and its spark torch igniter tested thousands of times.

The Lynx reaction control thruster (the 3N22) is a non-toxic, high performance, bi-propellant thruster. Bi-propellant means that the thruster uses a fuel and an oxidizer to run. The 3N22 has many attributes that make it perfectly suited to Lynx operations, for future use on satellites, and human spaceflight vehicles in orbit.

Astronaut Buzz Aldrin visits the XCOR hangar and fires the 3N22 thruster

The 3N22 has been fired hundreds of times. Its spark torch igniter, along with all of its predecessors has been tested tens of thousands of times.

Because XCOR uses nontoxic propellants, the thruster can be readily tested inside the XCOR hangar and handled without the need for more traditional and costly pressurized hazmat suits (commonly called SCAPE suits, for “Self Contained Atmospheric Protective Ensemble”).

SCAPE technicians ready for action

Overall savings in recurring and non-recurring costs for XCOR in using the non-toxic 3N22 is estimated to be over several million dollars, and a similar amount on an annual basis. Savings are derived from avoiding the following: costs associated with SCAPE suits, handling of toxic chemicals like hydrazine or nitrogen tetroxide, and the difference in cost savings between the fuel XCOR uses and hydrazine. These savings are passed on to our clients in the form of lower prices and safer flights.

As with the main propulsion systems discussed last week, the reaction control thrusters use liquid propellants. The 3N22 uses a combination of gaseous oxygen and our own proprietary fuel blend and can be considered “gas and go.” The thrusters require no touch labor between flights except for refueling from propellant storage tanks.

There are a total of twelve (12) 3N22 thrusters on the Lynx vehicle. They are mounted in six different locations, and are implemented with dual redundancy. Each thruster in a cluster of two runs off of separate feed systems to ensure operability even if we experience an anomalous condition with a thruster or feed system. The thrusters are located on the top side of the Lynx on the nose and the engine cowling (for nose up/down pitch control), on the two sides of the nose of the Lynx (for left/right yaw control) and on the two wing strakes (for roll control). You can see their position in the Lynx image (pairs of small black dots) and diagram (wherever RCS is mentioned) shown below.



Tomorrow we’ll hang out in the XCOR rocket engine test bunker.