What happened
On 27 January 2011, a Tornado GR4, registration ZG792, was conducting a simulated attack profile as part of an Operational Conversion Unit (OCU) long course. The aircraft, operated by XV(R) Squadron based at RAF Lossiemouth, was flying in formation with CACTUS 1 when the crew experienced a loud, machine-gun-like noise from the right side of the aircraft.
The pilot initially identified the sound as an engine surge and retarded both throttles to idle. However, the right engine's compressor speed continued to drop unexpectedly. Shortly after, the pilot observed REHEAT and R OIL P warnings. While attempting to shut down the right engine, a left engine fire warning appeared, accompanied by visible signs of fire.
Following the shutdown, the crew witnessed smoke and flames emanating from the rear of the aircraft. The situation escalated as multiple cockpit warnings appeared, including various fuel, oil, and vibration alerts. At approximately T2:50 into the emergency, the Command and Stability Auglemtation System (CSAS) failed, causing the tailerons to enter mechanical mode and significantly degrading flight control quality. Realizing the situation was critical, the pilot initiated a command ejection at 14:43:14 Zulu.
The investigation
The investigation examined the aircraft's history and the sequence of mechanical failures. ZG792 had completed 5240:10 flying hours and was nearing a scheduled maintenance interval. Investigators analyzed data from the Replacement-Accident Data Recorder (R-ADR) and Cockpit Voice Recorder (CVR), alongside visual observations from the following aircraft in the formation.
The investigation established that the aircraft impacted the sea at 384 KCAS in a diving attitude. The wreckage was eventually recovered from the seabed by a salvage vessel. The panel also reviewed the crew's training status and the technical performance of their aircrew equipment, noting that both life jackets and personal survival packs functioned as intended during the escape.
Findings
- The initial engine surge triggered a sequence of mechanical failures starting with the right engine.
- A hydraulic fire caused significant damage to the aircraft's systems.
- The failure of the CSAS was linked to wiring being burnt through by the ongoing fire.
- The fire eventually led to the deformation of a control rod, resulting in the loss of flight control.
- Both crew members sustained minor injuries and were rescued by a Coastguard helicopter.