Sikorsky Continues S-92 Improvement Program

 - December 3, 2011, 2:55 AM

Sikorsky’s ongoing total S-92 product improvement program emphasizes the offshore oil and gas mission, focusing on areas of availability, capability and safety, according to Spencer Elani, Sikorsky’s S-92 program manager.

While the aircraft is operated by a wide range of industries, from head of state to utility and search-and-rescue (SAR), the offshore market currently constitutes 60 percent of the S-92 fleet. As of October 1, the worldwide S-92 fleet consists of 147 aircraft in service that have accumulated more than 340,000 flight hours since the helicopter became operational in 2004. Availability rate for offshore operations has gone from 92 percent in 2009 to a current rate of 96 percent.

A key upgrade will be the automated rig approach system, allowing operators to conduct operations to oil rigs automatically in lower-minimum weather conditions with reduced pilot workload, resulting in improved availability and safety, said Elani. The system capitalizes on the flight-control software that Sikorsky developed for the SAR auxiliary flight control system (AFCS), which allows pilots to fly over a point on the earth, electronically mark it, then have the aircraft automatically fly an approach to that point and come to a defaulted-altitude hover.

Sikorsky has already tested the new rig approach system, and it is undergoing FAA type inspection and authorization flights, Elani said. It is expected to be certified and available sometime during next year’s second quarter.

Sikorsky is also in the process of certifying aircraft start-ups in up to 55-knot wind. Currently, the aircraft cannot be cranked at wind speeds greater than 45 knots.

The upgrades are not just to improve operations offshore in bad weather.

A major change to the aircraft will be an increase in mtow from 26,500 pounds to 27,700 pounds. FAA certification of the additional maximum weight is expected next year, with EASA certification in 2013.

Sikorsky has already certified an internal auxiliary fuel system consisting of two tanks stacked together, each holding 210 gallons of fuel. Each tank will increase range by about 140 nm or add an about an hour of time on station for SAR operations, Elani said. A redesign of the fuel system to allow additional external fuel capability is also being considered, he said.

Sikorsky is also looking at an upgraded active vibration reduction system to further improve the current choice of a three-or six-force generator system. “We are beyond the trade study phase and are talking to suppliers about the concept. But we’re still determining whether or not we are going to pull the trigger on that.”

A new version of the health and monitoring system (Hums) will also be installed. This is designed to improve the rotor tracking and balancing capability, reducing the amount of time needed for maintenance.

Although the aircraft is undergoing a significant upgrade program, Elani stated that currently there are no plans to add a fifth rotor blade and/or re-designate the aircraft the S-92B.