On 25 June 2001, an Embraer Bandeirante on a charter flight from
Sydney to Griffith, sustained an in-flight engine fire during
cruise. The pilot attempted to extinguish the fire, and believing
it to be extinguished, commenced a rapid descent to Young. Fog at
Young prevented a landing, and the pilot diverted the aircraft to
Cootamundra. Smoke entered the cabin, and the pilot transmitted a
MAYDAY. Only the right main landing gear extended when the landing
gear was selected down, but the pilot did not get an indication of
the landing gear position. Unaware that the right main landing gear
had extended, he prepared to make a gear-up landing. The aircraft
touched down on the right main wheel and settled onto the left
engine nacelle and nose, sustaining abrasion damage as it slid
along the runway. The fire in the right engine nacelle was still
burning when the aircraft stopped. The occupants egressed
uninjured, and bystanders extinguished the fire.
Technical investigation revealed that vibration from the worn
armature shaft of the right engine starter generator initiated a
fatigue crack in the fuel return line. Fuel leaked from the
fractured line during the flight, and was ignited by sparks or
frictional heat from the generator after the armature shaft
failed.
The pilot reported that he was unable to select the fuel cut-off
position with the right fuel condition lever and feather the right
propeller. While carrying out the engine fire emergency checklist
actions, the pilot did not complete all of the items of the
manufacturer's engine fire emergency checklist and the firewall
shut-off valve remained open. Fuel continued to flow to the fuel
control unit and feed the fire. The investigation was unable to
determine if the fire extinguisher bottle discharged effectively.
The fire continued to burn and heat conducted through the firewall
affected components in the wheel well. Smoke from the heat-damaged
components entered the aircraft cabin though gaps between the wing
root and fuselage.
Checklists carried on the aircraft did not contain appropriate
smoke evacuation procedures and the pilot's attempts to evacuate
smoke from the cabin were unsuccessful. Consequently, the
uncontained fire in the engine nacelle, and smoke in the cabin,
created a potentially life threatening situation and influenced the
pilot's decision not to delay the landing while attempting to
resolve the apparent failure of the landing gear to extend.
This occurrence demonstrates the need for error-free and
complete checklists to be available to pilots during emergency
situations. It also demonstrates the need for pilots to be familiar
with the systems of the aircraft they operate, and the emergency
actions to be taken in the event of abnormal or emergency
situations. Regular practice of those procedures is essential if
they are to be executed effectively. More thorough training and
checking of (charter) pilots, as proposed in the Civil Aviation
Safety Regulations Part 121B (charter) operations, if adopted, can
potentially improve pilot proficiency and knowledge in emergencies,
specific to the aircraft type.
As a result of this occurrence the ATSB recommended to the Civil
Aviation Safety Authority, the aircraft manufacturer and the
certification authorities that the temperature setting of thermal
relief valves on fire bottles, and the temperature setting of fire
detectors, be reviewed to avoid inadvertent discharge of fire
bottles. The ATSB also recommended that crews be provided with an
indication of fire bottle contents.