Sikorsky X2 family

[McColm]

Many thanks AEROFRANZ, for pointing me in the right direction.
Do you know if the C-130 has ever been fitted with a one step hull?
I know Lockheed came up with floats and tested a scale model but found a loss of 30% in its operational range.
Any ideas?

Thanks again.

 

[AeroFranz]

Not that i can think of, but the forum is a great resource for this kind of question. There are several C-130 threads you can search for, and if one does not match your topic, i suggest starting a new topic. you'll be surprised how much information will come up.

 

[yasotay]

Interesting sighting at the Army Aviation Center.

 

[overscan (PaulMM)]

Nice! Not likely to see that kind of thing on the way to work in Auckland

 

[Stargazer]

That's a mock-up, right? Or has the X2 flown and I completely missed that piece of information?

 

[elmayerle]

X2 has been flying for over a year and has been steadily expanding the envelope. A picture of its first flight featured prominently in Sikorsky's 2009 calendars.

 

[Stargazer]

Ooops... Last I heard it was the X-49A that was flying, not the X2. I seriously should spend a little less time on vintage aircraft and keep up to date with what's going on in the world! Thanks for filling me in!

 

[elmayerle]

No problem. *grin* It's easy for me since I'm contracting at Sikorsky. *chuckle* The main plant here in Stratford, CT is quite a change from my previous job with Lockheed-Martin in Fort Worth (much as Connecticut is a vast change from North Central Texas).

 

[flateric]

Sikorsky knew whom to hire!

 

[TomS]

That's a mock-up, right? Or has the X2 flown and I completely missed that piece of information?

Just to clarify something, X2 has flown, but the picture Yasotay posted is of a mockup, specifically of Sikorsky's Light Tactical Helicopter concept. The actual flying X2 is somewhat different.

 

[Sundog]

The last I had heard, they were about to engage the pusher prop during the flight tests. I assume that has since started. Any word on how envelope expansion is going?

BTW, WTG Elmayerle on the new job!

 

[TomS]

Yep, they did in-flight pusher engagement back in July.

They just hit 100+ knots a week or two back, according to a recent press release.

 

[AeroFranz]

with regards to the mockup, that's one BIG one-piece windshield...it does wonders for visibility, but how are they going to build it?

 

[yasotay]

with regards to the mockup, that's one BIG one-piece windshield...it does wonders for visibility, but how are they going to build it?

Having skipped lunch to chat with Sikorsky and watch all the wonderful Tom Clancy videos they brought, I can tell you that the forward visibility (assuming nothing gets put in the way) IS excellent. No pedals and potentially no collective were a bit much for this old aviator. Have a few more photos I will try to post.

 

[Just call me Ray]

What's with all the guys in orange suits? Looks like they're 'bout ready to collect whatever aliens come out of that thing

 

[elmayerle]

I believe Flight Test support, much as flight test instrumentation is "orange gear".

 

[yasotay]

I have been politely informed by someone in the know, that I am incorrect. There is a collective, in that the aircraft will have two side arm controllers for each position. If you look at the attached picture of the cockpit you can see one of them folded back (the "T" shaped device just inside the back of the door frame) out of the way to allow for entry/exit. This of course means they intend for the aircraft to be fly by wire (light maybe??).

The Sikorsky team also mentioned that the prop would be able to do reverse pitch for rapid deceleration and some very interesting maneuvers currently not done by standard rotorcraft. With this particular version of the X-2 they are planning on keeping the rotor diameter as small as possible to allow it to operate in the "urban canyons".

My impression is that Sikorsky is very aggressively working to get new rotorcraft technology out.

 

[Stargazer]

Let's hope they get a good contract from the military so that the big S-92 disappointment gets brushed away and forgotten!

 

[F-14D]

Let's hope they get a good contract from the military so that the big S-92 disappointment gets brushed away and forgotten!

I hope this technology does grow, but first, they've got to actually demonstrate they can reliably do what their brochures predict--this program is moving really slowly. Then, there's got to be a requirement to do what it can do, especially in the environment that's going to exist for the next few years. Finally, and possibly most importantly, they've got to devise a way that someone in Washington can take credit for it.

 

[elmayerle]

Let's hope they get a good contract from the military so that the big S-92 disappointment gets brushed away and forgotten!

Well, it's not been that big a disappointment as the sales are steady. Losing the "Marine One" contract hurt, but it may have been a good one to lose considering how badly the winner got hurt by "requirements creep" after the contract award (though Sikorsky might have sufficient experience to avoid that trap). I'm told that the main driver was that the EH101 interior is just enough wider than the S92 to allow certain desired interior items to be fitted.

 

[Triton]

Artist's impressions of Sikorsky X2 Technology helicopter concepts.

Source: http://www.flightglobal.com/blogs/flight-international/2008/07/sikorsky-x2-helicopter-concept.html#more

 

[Triton]

Photographs of Sikorsky X2 Technology-based Light Tactical Helicopter (LTH) mockup displayed at the Army Aviation Association of America annual convention 2009.

Sources:

http://www.blognetnews.com/virginia/author.php?author=joe&PHPSESSID=c7nsp3baos05r4959373fjqnl4
http://www.helinews.com.au/index.php?showtopic=567

 

[Triton]

Model of Sikorsky X2 Technology attack helicopter concept on display at the 2007 Modern Day Marine expo.

Source:http://defense-update.com/events/2007/summary/mdm07_vertical.htm

 

[Triton]

Sikorsky business development manager Jim Kagdis explains the aerodynamic and technical details of the X2 light tactical helicopter (LTH) mock-up unveiled at the Army Aviation Association of America annual convention 2009 The X2 LTH is a concept that could replace both the AH-6 Little Bird and the OH-58 Kiowa Warrior by the end of the next decade, Kagdis said. The propulsion system -- a coaxial rotor and pusher propeller -- should allow the helicopter to cruise at speeds up to 250kts.

http://www.youtube.com/watch?v=hwusQWZBXjg

 

[Triton]

Carey Bond of Sikorsky unveils the X2.
http://www.youtube.com/watch?v=1QYLYCMQMQo


Sikorsky Test & Evaluation chief test pilot describes the major systems in the company's X2 advancing blade concept technology demonstrator at the Heli Expo 2009 show in Anaheim, California on 23 February 2009.
http://www.youtube.com/watch?v=rWVPh5Q1qi8

 

[yasotay]

X-2 is at West Palm gearing up for high speed expansion. Getting fairings and such for rotors. Most likely getting all of the turning parts checked out for flight quals.

 

[F-14D]

While the concepts are exciting, so far they've flown seven times in 18 months and achieved a maximum speed of 106 knots. I hope this program keeps going, but given the glacial pace of all aerospace development nowadays, I wonder how many of us will be retired before there's an operational version in production.

 

[Triton]

Source: http://www.gizmag.com/sikorskys-x2-demonstrator-first-flight/9886/

 

[yasotay]

While the concepts are exciting, so far they've flown seven times in 18 months and achieved a maximum speed of 106 knots. I hope this program keeps going, but given the glacial pace of all aerospace development nowadays, I wonder how many of us will be retired before there's an operational version in production.

I would just like to be alive! ...and preferably still mobile ;D

I believe I read someplace that the Sikorsky X-2 now has the end of this year as a target for ~250 knots. I take this to mean that they are still on it but somewhat more fincially constrained.

 

[TomS]

They had a manufacturing problem with the gearbox which set them back.

http://www.flightglobal.com/articles/2010/02/17/338307/sikorsky-x2-down-but-not-out.html

 

[F-14D]

They had a manufacturing problem with the gearbox which set them back.

http://www.flightglobal.com/articles/2010/02/17/338307/sikorsky-x2-down-but-not-out.html

OK, so they flew a total of seven times in only 14 months. Program is still years behind schedule. Here's hoping the speed picks up (in more ways than one) in 2010.

 

[yasotay]

From Aviation Week.

Sikorsky X2 Aims for World Speed Record

Feb 23, 2010

By John Morris/Show News
HeliExpo 2010/Houston, Tex


The Sikorsky X2’s attempt to break the world speed record for rotorcraft later this year could determine the future path of helicopter development at the Connecticut-based company.

The X2 intends to achieve 250 kts by the end of the year, far ahead of the world speed record held by a Westland Lynx at 216.45 kts and the best cruising speed achieved by production helicopters of around 150 kts. They are limited to that envelope by current rotor technology.

The X2 features closely separated coaxial rotors with very rigid blades, active vibration damping, fly-by-wire and a pusher propeller.

It is, says Mark Miller, vice president of research and engineering at Sikorsky, an enabler. If it achieves 250 kts then Sikorsky will pursue that path in future developments. If the technology fails to deliver then the X2 will, after all, have proved its value as a technology demonstrator.

“Once we do that [hit 250 kts] we will be open to teaming or investors. That’s the enabler,” said Miller.

The X2 has recently been grounded by metal flaking in its transmission gearbox but will fly again soon. The first target when it does so: 150 kts.

The aircraft has now been fitted with streamlined cuffs and fairings on the top fuselage and enclosing the rotor mast. These will cut drag by 50%, said Miller, which is very significant and will help the X2 hit that 250 kts target.

 

[Sundog]

Good luck Sikorsky, I hope it works out. We need some new, applicable, rotor tech in this country.

 

[Triton]

Link to Aviation Week article posted by yatosay:

http://www.aviationweek.com/aw/generic/story.jsp?id=news/awx/2010/02/23/awx_02_23_2010_p0-206782.xml&headline=Sikorsky%20X2%20Aims%20for%20World%20Speed%20Record&channel=busav

 

[donnage99]

Are that many blades kinda contradict the trent of reducing RCS nowaday?

 

[yasotay]

While no one ignores RCS, it is less concern with rotorcraft because to date there have been very few if any radar ADA engagements of helicopters. There is more focus on signature reduction of acoustics and infra-red as those are the primary threats to helicopters. Rotating un-ducted rotors are very hard to hide against modern radar. Consider all of the discussion of the PAK FA engine inlets and the implications of RCS, then consider the implications of huge blades (in comparison) on rotorcraft. If there is a radar threat then helicopters will use terrain masking to block potential acquistions.

 

[donnage99]

Helicopters fly at a different altitude from fighter jets such as f-22 or T-50, and beside, stealth fighters are designed to operate in access-denied airspace, with multiple radar threats from air and ground. So if I'm not wrong here, the radar threats between fighter jets and helicopters should also be different and not relevant for comparison.

To me, RCS reduction doesn't neccesary have to be stealthy. It just means less effective range for enemy radar to engage, thus allowing more options for battle plannings and operations. And I think this factor has been reflected in the 2 most recent "big" programs such as commanche, UCAR.

I just find it hard to imagine that if the Army is gonna go with a clean sheet design, they will not place low-observable on the priority list as much as the last 2 programs.

 

[yasotay]

Certainly it is correct that rotorcraft generally do not operate at the altitudes that high speed aircraft operate. A side note, when there is not a radar threat, such as the combat environments we see today rotorcraft do fly higher (2000 feet to 10,000) to stay out of the range of the most prevalent threat to them (small arms). I agree that for the most part the radar threat that rotorcraft would have to contend with are a different set of systems than that of an F-22 and other fixed wing aircraft, with a few notable exceptions.

That said, to my knowledge there have been fewer than ten helicopters shot down by radar guided weapons since helicopters began operating in combat. If someone knows differently I would certainly like to know. The vast majority have been lost to small caliber weapons, unguided rockets and more recently MANPADS. Given the difficulty in making rotating components stealthy (main & tail rotors, tilting rotors, compound rotors with multi-directional rotating components) and that they are usually only able to be made stealthy in one spectrum (i.e. edgewise) it becomes near impossible to make a rotorcraft stealthy enough to overcome the every changing radar technology. By this I mean it is possible that you can make a helicopter hard to see on a radar if it is hovering with the rotor system in plane with the radar. However if you bank around and show more of the rotor disk, the radar is able to see the aircraft very well. This is why the Comanche had a shrouded tail rotor so that only the main rotor was "visible" head on. However as soon as you turned sidewise, the tail rotor (even covered) shows up. This is why for aircraft able to hover, hiding in the radar blind spot behind buildings and hills, etc., remains the most viable method.

There has been a tremendous amount of work done investigating the need for RCS reduction around the world and so far it just does not seem to be worth the expense. The mot cost effective means toward survival appears to remain reduction of IR signature and ballistic tolerance.

 

[donnage99]

There has been a tremendous amount of work done investigating the need for RCS reduction around the world and so far it just does not seem to be worth the expense. The mot cost effective means toward survival appears to remain reduction of IR signature and ballistic tolerance.

If you mean the inherent lack of an operational "stealth" helicopters in the market, I humbly disagree. The reason why there is a lack of "stealth" helicopters is not because it's not worth the expense, but rather the lack of new clean sheet designs altogether. The last 2 programs that use clean sheet designs, comanche and UCAR, all placed RCS reductions
Though we have yet to achieve RCS reduction in helicopters to really call them stealthy and thus have the platforms solely rely on the small RCS to evade enemy attacks like f-22, that doesn't mean that it will not yield any advantages. It does and thus was greatly sought. And the last two programs strongly reflect that. It's just extremely strange in my opinion that the Army will be willing to revert back from that thinking.

Your point on the kill count is a very valid one though. The thinking of using attack helicopters as 'tank killers" in a conventional Cold War doctrine has given way to using them in low intensity conflict in today. So the fear of radar threats are not as great as the concern for reducing IR and acoustic signatures.

 

[quellish]

At a high level, the survivability problem is the same for a rotorcraft as a fighter - but the numbers are different. Detection and engagement ranges are very different for helicopters and jets, but it's the relative differences that matter. For example, an F-117 can be engaging you and you would not even know it. An Apache is detectable long before it's within small arms range. There's the problem in a nutshell.
The X2 could spend less *time* in the defender's engagement zone, which may be an advantage.