An ATSB report released today into the crash of a Glasair III at Jandakot in 2013 has found no definite cause, but hints at a modification issue.
The amateur-built experimental aircraft suffered an engine faiure on take-off from Jandakot on 9 December 2013, and crashed on landing in a sports field after one wing struck a goal post. Both pilot and passenger were severely injured and the aircraft destroyed by fire.
According to the ATSB report, the remains of the aircraft were too damaged to determine a specifc cause, but suggests the problem may lie with a modification to the ignition system.
"During the aircraft’s construction, modification of the electronic ignition system incorporated a single point of failure in the intended dual system, increasing the risk of the simultaneous failure of both systems and a total loss of engine power," the report says.
"In addition, the connector plug used for the modification was inappropriate for the in-line installation, increasing the risk of its disconnection and disabling the ignition system.
"Examination of the engine found that the single wiring harness for the ignition system was disconnected from the connector plug. However, due to the level of impact and fire damage sustained by the aircraft, the ATSB was unable to conclusively establish if this occurred in flight, resulting in the total engine power loss, or during the early stages of the impact sequence."
In the report's summary, the ATSB goes on to warn that incorporating a single point of failure during construction or modification can inadvertantly eliminate redundancy in critical systems.
The full report can be downloaded from the ATSB website.