New medium-sized commercial helicopters have taken longer than expected to arrive, but pent-up demand is putting pressure on manufacturers to complete certification of mission configurations and deliver into multiple market segments almost simultaneously.

Sikorsky handed the first S-76Ds to Bristow Group in December. The aircraft are configured for offshore oil-support services in the Gulf of Mexico, but delivery of the first VIP-configured helicopter is imminent. Emergency medical service (EMS) and search-and-rescue (SAR) variants will follow this year.

AgustaWestland planned to deliver the first AW189 around the turn of the year, also to Bristow Group, while Eurocopter is expecting delayed certification of its EC175 early in the year, with deliveries to offshore operators including Bristow to begin in the second half. Bell Helicopter will fly its Model 525 this year, for entry into service in 2015.

The improved S-76D has more-powerful Pratt & Whitney Canada PW210S turboshafts and a Thales integrated flight deck, four-axis autopilot, active vibration control, composite main rotor blades and an optional rotor ice-protection system.

Since receiving delayed FAA certification of the baseline S-76D in October 2012, Sikorsky has been working to certify mission kits for the latest version of its popular intermediate twin helicopter. The 12-passenger offshore configuration is the first to be approved and delivered.

“There is almost as much work in certifying the kits and options as in the base aircraft,” says Carey Bond, president of commercial arm Sikorsky Global Helicopters. “We were successful out of the gate in selling into all four market segments—offshore, VIP, heavy SAR and EMS—which meant a huge amount of certification work.”

In addition, Sikorsky has grown the capability of the S-76D beyond the baseline certification, increasing gross weight to 11,875 lb. and expanding the hot and cold operating temperature range. “The original S-76 was not a strong performer in the Middle East because of its installed power. Now we have that in spades,” he adds.

Demand from multiple markets resulted in mission-kit certification tasks becoming intermixed, Bond says. “We had not anticipated EMS sales, and we thought the market would be for light SAR, not heavy.” Certification tests on the VIP configuration were completed in late 2013, the SAR variant is in flight test for delivery to Japan by mid second-quarter, and delivery of the EMS configuration is planned for August 2014.

Expanding the capability includes extending the S-76D's cold-weather operating temperature down to -20F, with a goal of -40F, and increasing hot-day density altitude to 10,000 ft., with a goal of 15,000 ft. Software updates for the Thales cockpit are next, Bond notes.

Compared with the previous S-76C++ model, the S-76D is 15 kt. faster at 171 kt. in straight and level flight, he says. The D is 5% more fuel efficient than the C++ and the gross-weight increase helps offset increased weight from new equipment such as crash-attenuating stroking seats.

With a backlog exceeding $700 million, Sikorsky had delivered almost 30 green aircraft into completion by year-end and inducted the 51st cabin—manufactured by Aero Vodochody in the Czech Republic—on to the final-assembly line at Coatesville, Pa. “We are in full-rate production,” Bond says.