A preliminary incident report, filed yesterday, reveals a hairy landing for the pilots of a Bistrow Sikorsky S-92A oil rig transport helicopter in Louisiana on 19 January.
A mechanical issue presented itself to the crew of three onboard N920L as it returned its 15 passengers to the Air Logistics Galliano heliport (2LS0) in Galliano, Louisiana from the Green Canyon 858 off-shore helipad in the Gulf of Mexico.
"During the initial approach into 2LS0, as airspeed reduced through approximately 70 knots, the helicopter began a right yaw of more than 100 degrees that could not be stopped by application of left pedal," the NTSB writes in the report.
"The crew immediately lowered the nose to regain airspeed and streamline the aircraft. They diverted to the South Lafourche Airport (GAO), Galliano, Louisiana and performed a successful roll on landing, touching down at approximately 72 knots, utilizing differential braking to maintain runway heading"
Wow - now that's some Chuck Yeager-type piloting under duress.
The problem doesn't appear to be linked to transmission troubles that have plagued the S-92A, as emphasized in last week's final report on the 2009 Cougar Helicopters crash off of Newfoundland.
Instead, this one appears to be a case of maintenance error.
"An after landing inspection showed that the tail rotor pitch change beam retaining nut was missing. Recent maintenance had been performed," say the NTSB.