First Flight for Sikorsky-Boeing’s Defiant Delayed Until 2019

Sikorsky-Boeing's Defiant

Sikorsky

Despite plans for the Sikorsky-Boeing Defiant helicopter to fly in 2018, the schedule has now slipped to next year, company executives said Dec. 12.

The Defiant — which is based on Sikorsky’s X-2 technology — is an advanced rotary-wing platform developed for the Army to inform requirements for future vertical life aircraft. The system is part of the service's joint multi-role technology demonstrator effort. The initiative is a precursor to the Army’s future vertical lift program, which is meant to replace legacy helicopters with a family of new systems in the 2030s.

While the Defiant is now fully built, recent discoveries with the power­train system test bed, or PSTB, system has caused delays, delaying first flight until early 2019, said Rich Koucheravy, Sikorsky’s director for business development for future vertical lift.

The test bed, which is a replica of the Defiant minus the landing gear, is meant to reduce technical risk. Issues discovered with the PSTB can then be tweaked on the Defiant. Both are located at Sikorsky’s West Palm Beach, Florida, facility.

“I won't get into the nature of the discovery,” Koucheravy said. “I will tell you that we expect these sorts of things to come up. … We're working those fixes. Our goal will be to get the PSTB back in operation shortly.”

The Sikorsky-Boeing team plans to have the fixes — which Koucheravy characterized as “mundane” — completed within the next week or two, after which the system can begin running again — but not before pushing first flight into 2019, he said.

While this is not necessarily “what a lot of folks would have liked — not necessarily what we have liked — we continue to build confidence in our configuration through the PSTB, through our software integration lab for flight control — both hardware and software — and those operations are continuing to inform our engineers so that when we do begin flying Defiant we've removed as much risk as possible,” he told reporters during a teleconference.

The Defiant has continued to face schedule slippage while Bell Helicopter — which is also participating in the joint multi-role demonstrator effort — first flew its V-280 Valor aircraft last year. The Valor is based on Bell’s V-22 tiltrotor technology.

Randy Rotte, Boeing’s director of global‎ sales and marketing for cargo helicopters and future vertical lift, said that up until the recent discoveries with the powertrain test bed, Defiant was on track to fly before the end of this year.

“Everything for us runs through PSTB,” he said. “We have to run it a certain number of hours for our flight safety committee before we get granted a certificate to actually get to fly.”
Rotte noted the issues — which were discovered within the last couple of weeks — were not particularly problematic.

“It’s not like this is a, ‘Oh my goodness, we discovered something terrible and … we have to redesign something,'” he said. “This is truly just a mechanical-type fix to something that we observed on PSTB … [and] we'd rather get it done now before we have to do it on the aircraft.”

Koucheravy noted that the Army was immediately notified about the issues.

“They're part of our program and we keep them fully aware,” he said. “We provide them very regular updates, not just at the program level, but our company leadership sends a regular report to Army aviation senior leaders to keep them informed of what we're doing.”

Koucheravy wouldn’t speculate on whether the delays were causing headaches for the Army, but noted that the service is still conducting an analysis of alternatives ahead of a potential decision in 2021 to move the joint multi-role demonstrator effort into a formal program of record, which would be known as the future long-range assault aircraft.

Topics: Army News, Rotary Wing