GATINEAU, QC, May 13, 2013 /CNW/ - A Transportation Safety Board of
Canada (TSB) investigation report (A10P0242) released today identified
disrupted fuel flow as the likely cause of the crash of a Transwest
Helicopters Ltd. Bell 214B-1 helicopter, which was fighting fire
approximately 20 nautical miles northwest of Lillooet, British
Columbia. The helicopter lost power, touched down hard on uneven
terrain, and rolled over onto its side. The 2 pilots escaped with minor
During the 29 July 2010 flight, after the pilots successfully carried
out 12 water drops with the helicopter, the engine lost power. The
pilot-in-command (PIC), seated in the left-hand seat, turned the
helicopter left and downhill and descended toward an open area to land.
As the helicopter neared the ground, the PIC leveled the helicopter and
reduced the rate of descent; however, the main-rotor struck the terrain
on the right side, and the helicopter came to rest on its left side
facing uphill. The tail broke off, and the tail rotor assembly landed
30 feet away. The helicopter was substantially damaged, and there was a
small post-crash fire.
Investigators found that the engine fuel control unit (FCU) was
contaminated with metallic debris, which likely disrupted fuel flow and
caused the engine to lose power. A review of maintenance procedures was
undertaken by the TSB, which revealed that overhaul procedures and
documentation were unclear and lacked detail, and that recurring
component failures were not tracked and monitored as required by the
approved maintenance organization. The absence of tracking and
monitoring FCU failures increases the risk that component problems will
not be fixed before failure.
The investigation further noted that inspections did not include
complete disassembly of sub-component parts of the FCU, and some FCUs
were misidentified when incomplete modifications were carried out.
Shortly after the occurrence, Honeywell, the FCU manufacturer, issued 2
service bulletins for the misidentified FCUs, reducing the time between
overhauls from 2400 hours to 1800 hours, and later recalled all these
The TSB is an independent agency that investigates marine, pipeline,
railway and aviation transportation occurrences. Its sole aim is the
advancement of transportation safety. It is not the function of the
Board to assign fault or determine civil or criminal liability.
The TSB is online at www.tsb.gc.ca. Keep up to date through RSS, Twitter @TSBCanada, YouTube, Flickr and our blog.
SOURCE: Transportation Safety Board of Canada
For further information:
Transportation Safety Board of Canada