The ATSB is strongly encouraging pilots of experimental powered gliders to install fire protection between the engine compartment and cockpit following its investigation into a fatal accident where a modified jet-powered glider was destroyed by fire.
The call follows the ATSB’s investigation into a 21 January 2018 accident where a Schleicher ASH-25E glider which had been retrofitted with two small gas turbine engines caught fire not long after being launched from the Bathurst Gliding Club’s Piper’s Field airfield in central west NSW.
The experienced pilot had planned to conduct a solo cross-country flight, and eight minutes into the flight, the glider had climbed to about 2,200 feet in a thermal. Shortly after, the glider abruptly started to descend and track back towards the airfield, and witnesses reported seeing smoke or liquid trailing from behind the glider’s cockpit.
At about 1,100 feet, the pilot jettisoned the front-seat canopy but did not exit the glider, possibly due to incapacitation. Fire engulfed more of the rapidly-descending glider’s fuselage before it collided with the ground in a nose-down attitude. The pilot was fatally injured and the aircraft was destroyed.
The ATSB strongly encourages pilots of powered experimental gliders to install fire protection.
Due to the severity of the post-impact fire, the ATSB investigation could not determine the ignition source, but did establish that the glider’s cockpit and engine housing were not separated by a firewall.
“Pilots of powered experimental gliders are strongly encouraged to install fire protection between their aircraft cockpit and the engine housing,” said ATSB Director Transport Safety Stuart Macleod.
“The ability to exit a glider relies on avoiding incapacitation that can happen quickly in the event of in-flight fires.”
The accident glider had originally been fitted with a small Rotax piston engine driving a propeller mounted on a retractable pylon that allowed the glider to undertake self-sustaining flight (that is, maintaining level flight or initiating a climb, but not for launching). In 2010, the pilot had removed the original engine and propeller, replacing them with two small Titan AMT gas turbine engines for self-sustaining flight, with two 25-litre collapsible fuel cells installed into the wing root.
Once fitted with the jet engines, the glider was flown under an experimental type certificate. The Gliding Federation of Australia’s Manual of Standard Procedures states that flying experimental category gliders “is entirely on the basis of voluntary acceptance of risk by the persons who elect to do so".
Following the accident, the Gliding Federation of Australia published an Airworthiness Directive and an Airworthiness Advice Notice, both entitled Engine Compartment Fire Containment and Retardation, which provide guidance regarding fire safety.
The Airworthiness Directive requires all powered glider operators to inspect and repair fire retardant paint, fit ‘in case of engine fire’ cockpit placards, and ensure there is no flammable material on the cockpit side of any firewalls.Last update 20 December 2019