Faulty thrust control blamed

A faulty second-stage thrust vector control (TVC) actuator has been blamed for the failure of the Orbital Sciences (OSC) Taurus booster to launch the OrbView 4 and QuikTOMS satellite from Vandenberg AFB, California, on 21 September.

OSC says the actuator driveshaft seized up 5s after second-stage engine ignition, causing the vehicle to veer off course and eventually lose the thrust required to reach orbit.

The actuator was already due to be replaced on further Taurus launches. The same actuator was fitted to the TVC on the Pegasus booster which went out of control during a Hyper X, X-43A scramjet test flight in June. The actuator was not blamed for that failure, however.

Source: Flight International