Sikorsky-Boeing SB-1 Defiant
After years of secrecy and CGI, we're finally getting to see the Sikorsky-Boeing dream team's SB>1 Defiant ultra-high-speed helicopter in real life. Now they just have to prove it works.
https://breakingdefense.com/2018/12/def ... r-chopper/
SB>1 Defiant Takes Flight: Can It Catch Bell?
The thing that delayed Defiant, it turns out, is the same thing that makes it really attractive to the Army
https://breakingdefense.com/2019/03/sb1 ... atch-bell/
JUNE 28, 2019
https://www.thedrive.com/the-war-zone/2 ... tem-issues
Boeing and Sikorsky are gathering more propulsion system data on the ground to support further flight testing of their SB>1 Defiant advanced compound helicopter. After three successful flight tests, starting with the helicopter's first flight in March 2019, the two firms are making tweaks to expand the helicopter's flight envelope.
https://www.thedrive.com/the-war-zone/2 ... tem-issues
- Elite 1K
- Posts: 1076
- Joined: 21 Aug 2010, 22:52
zerion wrote:JUNE 28, 2019Boeing and Sikorsky are gathering more propulsion system data on the ground to support further flight testing of their SB>1 Defiant advanced compound helicopter. After three successful flight tests, starting with the helicopter's first flight in March 2019, the two firms are making tweaks to expand the helicopter's flight envelope.
https://www.thedrive.com/the-war-zone/2 ... tem-issues
Thanks.
So as I read this, in sixth months they've managed to fly three times at a blazing ten knots at 30 feet and the a/c is grounded again while they work on propulsion systems. In June they said they were about to restart the flight test, but does anyone know if they've actually flown again?
Couple of notes on the article. The S-97 has hit 207 knots, but despite what the article says, is there any reference that says they've actually achieved 220 knots (I think I remember reading somewhere Sikorsky saying the S-97 demonstrator may not be able to reach its projected top speed) ? Also, by the time the article came out the V-280 had demonstrated speeds in excess of 300, not 280, knots.
4 Flights, 3 Hours, 20 Knots: Defiant Inches Ahead
Mechanical fixes kept the SB>1 compound helicopter grounded for weeks this summer, but the Sikorsky-Boeing team insists they can catch up...
https://breakingdefense.com/2019/10/4-f ... hes-ahead/
- Elite 1K
- Posts: 1076
- Joined: 21 Aug 2010, 22:52
zerion wrote:4 Flights, 3 Hours, 20 Knots: Defiant Inches Ahead
Mechanical fixes kept the SB>1 compound helicopter grounded for weeks this summer, but the Sikorsky-Boeing team insists they can catch up...
https://breakingdefense.com/2019/10/4-f ... hes-ahead/
Interesting quote in that article. They think they'll be able to achieve the Army's minimum mandated speed (not their promised speed, just the Army minimum) in another six months, “if we have no other significant things we learn along the way,”.
That's from their own Program Manager. That does not strike me as a statement brimming over with confidence.
- Elite 2K
- Posts: 2582
- Joined: 12 Jan 2014, 19:26
https://www.flightglobal.com/helicopter ... 17.article
The Sikorsky-Boeing SB-1 Defiant continues to expand its flight envelope through sorties each week, executing the mission elements required for Future Vertical Lift, most recently exceeding 100kt and performing maneuvers at 30° angle of bank at the Sikorsky Development Flight Test Center in West Palm Beach, Florida,” the companies say.
The Sikorsky-Boeing team said in October 2019 they planned to increase the SB-1’s speed during test flights in 40kt increments until reaching 230kt by the end of the first quarter in 2020.
At the NASA Ames Research Center, a subscale Defiant model has been successfully tested at 250kt, the companies said.
- Elite 2K
- Posts: 2582
- Joined: 12 Jan 2014, 19:26
While the Sikorsky is behind the curve compared to Bell's submission, progress is being made.
https://breakingdefense.com/2020/06/fvl ... s-for-288/
https://breakingdefense.com/2020/06/fvl ... s-for-288/
- Elite 1K
- Posts: 1076
- Joined: 21 Aug 2010, 22:52
charlielima223 wrote:While the Sikorsky is behind the curve compared to Bell's submission, progress is being made.
https://breakingdefense.com/2020/06/fvl ... s-for-288/
235 mph is 205 knots, which is a more apples to apples number to use when comparing with Bell's submission (over 300 knots) which was able to fly over 15 months sooner.
On October 12 it was proudly announced that the SB>1 had reached 232 knots. However if you look closely at the event you'll find that was achieved in a descent. In level flight they've only gained six knots (to 211) in four months. Also part of the announcement was that it used "only" two-thirds prop torque and engine power to hit 211 knots. Apparently they used a bit under 50% to get to 205, so we can see the effects of drag here. People a lot smarter than me are starting to wonder if the SB>1 will actually get to the promised 250 knot sustained speed.
Some report that the Defiant has now flown 23 hours total. That's less than 1 1/4 hr a month, so progress has to be assessed as somewhat less than breathtaking.
aaam wrote:charlielima223 wrote:While the Sikorsky is behind the curve compared to Bell's submission, progress is being made.
https://breakingdefense.com/2020/06/fvl ... s-for-288/
235 mph is 205 knots, which is a more apples to apples number to use when comparing with Bell's submission (over 300 knots) which was able to fly over 15 months sooner.
On October 12 it was proudly announced that the SB>1 had reached 232 knots. However if you look closely at the event you'll find that was achieved in a descent. In level flight they've only gained six knots (to 211) in four months. Also part of the announcement was that it used "only" two-thirds prop torque and engine power to hit 211 knots. Apparently they used a bit under 50% to get to 205, so we can see the effects of drag here. People a lot smarter than me are starting to wonder if the SB>1 will actually get to the promised 250 knot sustained speed.
Some report that the Defiant has now flown 23 hours total. That's less than 1 1/4 hr a month, so progress has to be assessed as somewhat less than breathtaking.
IMO The V-280 has it in the bag. Raider will win FARA.
"There I was. . ."
Who is online
Users browsing this forum: No registered users and 1 guest