B4 Hybrid Rocket Motor "Running like a dream"

22nd, June, 2002 - MARS today carried out the latest in it's ongoing programme of tests of the B4 hybrid rocket motor ahead of a planned altitude record bid in the near future.

The hybrid rocket motor was static fired at a secure private test facility, in a stunningly successful test run that saw the motor operate to within 10% of original specifications for an extended period of time. The hybrid rocket motor delivered almost a full quarter of a metric ton of thrust for over ten seconds before the propellants were exhausted as the motor went in to blow-down mode.

The firing was viewed by the test team from a remote operations station where the hybrid rocket motor was monitored over three CCTV links and a series of remote temperature and pressure sensors connected to the motor and to the thrust stand, as well as a spectrometer monitoring the hybrid rocket motor exhaust plume. The firing was without doubt the most well instrumented static test any UK amateur team have ever conducted.

One team member who was at the test site reported: "The motor lit the moment we opened the valve, the oxygen ignition system worked brilliantly again. We all just sat there in awe as the ground literally shook for ten seconds while the motor ran, there were clearly defined mach diamonds and shock rings visible in the exhaust plume through most of the run... it was VERY impressive".

The B4 hybrid motor will be undergoing further static and flight testing this year with the aim of it becoming a cheap 'off-the-shelf' propulsion system for low to medium altitude work as the new, larger propulsion systems under development by MARS come on line.

The B4 hybrid rocket motor developed from scratch by MARS, is currently the main workhorse rocket motor used by MARS, and has been both static tested and flight tested. Other currently operational MARS hybrid rocket motors are the B1 and B2 composite cased hybrid rocket motors, designed for smaller launch vehicles as well as for upper stages. The B1 and B2 hybrid rocket motors were also developed from scratch and flight tested by MARS. The other, older MARS developed hybrid rocket motors are now used for fuel characterisation and development of ignition systems.

Below: The B4 hybrid rocket motor being static test fired - June 2002