Detailed investigations by the Republic of Singapore Air Force (RSAF) and Lockheed Martin (LM) have determined the cause of the accident. The flight data recorder recovered from the crashed F-16 showed that its pitch rate gyroscopes gave erroneous inputs to the flight control computer. This led to the pilot being unable to control the plane at take-off.
All F-16 fighter jets are fitted with four such gyroscopes and simultaneous failure of the gyroscopes is a very rare occurrence. As such, LM does not stipulate any maintenance for the pitch rate gyroscopes in the F-16 aircraft. This is the first such simultaneous malfunction of the pitch rate gyroscopes for the RSAF's entire F-16 fleet that has operated over 35 years. The RSAF, with LM, will undertake further studies to determine the specific cause/s for the gyroscope malfunction that resulted in this crash.
As the cause of the F-16 crash has been elucidated, the RSAF F-16 fleet will resume flying. But as an added precaution, each F-16 pitch rate gyroscope will be checked and cleared before resumption of flights.