Sikorsky Unveils S-92 Phase IV Gearbox for Commercial Helicopters

Sikorsky has introduced the S-92 Phase IV main gearbox, which includes an auxiliary lubrication system that automatically engages if primary oil pressure is lost, allowing helicopters to continue flying without immediate landing.

The new gearbox has undergone over 800 hours of testing, with Federal Aviation Administration (FAA) certification expected in 2025. Four units have been completed at Sikorsky’s Stratford headquarters, and customers are competing to become the first to adopt the system.

Sikorsky has invested more than $100 million in the gearbox, designed to improve the S-92 helicopter’s reliability for offshore energy, search and rescue, and other critical missions. The S-92 helicopter, known for its use in deepwater operations, averages over 1,500 flight hours annually in the offshore energy sector.

The company recently announced other S-92 enhancements, including longer inspection intervals and a one-time life extension for specific main gearbox housings, reducing downtime and allowing operators to extend service life by up to 1,200 hours.