The aviation regulator in the United States is ordering that all Sikorsky S-92A helicopters must be inspected for gearbox cracks before Aug. 1, 2012.

It is the type of chopper Cougar uses to transport offshore oil industry workers in the province.

The Federal Aviation Administration issued the directive Tuesday.

The order was prompted by an incident in which a crack in a S-92A main gearbox housing allowed oil to leak from the main gearbox.

The FAA said a leak could ultimately result in the loss of control of the helicopter.

Canada’s Transportation Safety Board determined a catastrophic loss of oil from a Cougar S-92A gearbox resulted in the tragic crash three years ago that killed 17 people off the coast of Newfoundland.

An earlier FAA bulletin required that a S-92A cannot fly more than ten hours between gearbox inspections.

The new directive requires companies to immediately fix a crack found during inspection, an expensive repair that can costs more than $250,000 dollars.

Shawn Coyle, an aviation industry consultant and former helicopter test pilot, said the impact on Cougar should be minimal because the inspection can probably be done during routine maintenance.