New rules for large firefighting aircraft, following Fitzgerald River National Park crash

The Australian Transport Safety Bureau is set to implement new rules for firefighting aircraft, following the end of an investigation into a plane crash in WA’s South West last year.

Minimum safe drop heights will now be introduced for large firefighting aircraft around the country to ensure pilots stay at least 200ft above the ground while in flight.

The recommendation comes after Bomber 139 - a Boeing 737 aircraft converted into a large air tanker - hit a ridge and crashed while dropping fire retardant in the Fitzgerald River National Park near Hopetoun on February 6 last year.

ATSB Chief Commissioner Angus Mitchell said the plane’s captain had failed to detect a rise in the terrain, which likely contributed to the captain allowing the aircraft to enter a “low-energy state” during the drop.

“The ATSB’s investigation found that the aircraft was conducting a drop at a low height and airspeed over descending terrain, which required the use of the idle thrust engine power setting and a high rate of descent,” he said.

“Towards the end of the drop, the aircraft’s height and airspeed decayed as it approached rising terrain that had not been detected, and was not expected, by the aircraft captain.”

The investigation stated neither the operator - Coulson Aviation - or the relevant Western Australian Government Departments had published a drop height for large air tankers which meant pilots could exercise their own judgement to improve accuracy.

Coluson Aviation has also since implemented its own 200ft drop requirement for its air tankers, while the ATSB confirmed the Department of Fire and Emergency Services and the Department of Biodiversity, Conservation and Attractions were also amending procedures to introduce drop heights.