Probe of Newfoundland copter finds broken gearbox
By Scott Haggett
CALGARY, Alberta (Reuters) - Canadian investigators on Friday found a damaged part in the gearbox of a helicopter that crashed off Newfoundland last week, killing 17, and expect the U.S. Federal Aviation Administration to ground similar aircraft until the part is replaced.
Canada's Transportation Safety Board (TSB) is examining the wreckage of the Sikorsky S-92 helicopter owned by Cougar Helicopters that crashed March 12 while ferrying workers to offshore oil facilities.
Only one person survived when the aircraft plunged into the North Atlantic about 40 miles southeast of St. John's. The wreckage was pulled from the ocean floor earlier this week.
Investigators have found a broken main gearbox filter bowl assembly mounting stud, a part that Sikorsky Aircraft Corp had previously advised owners of the S-92 to replace by next January.
"We can't say that it caused the crash but it could be a contributing factor," said Charles Laurence, operations team lead for the TSB. "It may have led to a loss of oil."
Minutes before the crash, the helicopter's pilot reported problems with oil pressure in its main gearbox, reports said.
On January 28 Sikorsky issued an alert service bulletin that called for the titanium studs to be replaced with steel mounting studs within 1250 hours of flight time or within a year of the alert, whichever came first.
Now the TSB says it expects the FAA to soon issue an emergency Airworthiness Directive stipulating the part be replaced immediately. Continued...