Go Back  PPRuNe Forums > Aircrew Forums > Rotorheads
Reload this Page >

Sikorsky Raider X - FARA contender

Wikiposts
Search
Rotorheads A haven for helicopter professionals to discuss the things that affect them

Sikorsky Raider X - FARA contender

Thread Tools
 
Search this Thread
 
Old 14th Oct 2019, 23:59
  #1 (permalink)  
Thread Starter
 
Join Date: Feb 2006
Location: The Alps
Posts: 3,145
Received 98 Likes on 53 Posts
Sikorsky Raider X - FARA contender

Today Sikorsky announced the Raider X for FARA competition ..

https://www.lockheedmartin.com/en-us...-raider-x.html


chopper2004 is online now  
Old 15th Oct 2019, 03:18
  #2 (permalink)  
 
Join Date: Dec 2000
Location: Arlington, Tx. US
Posts: 696
Likes: 0
Received 11 Likes on 7 Posts
Sikorsky AUSA FARA Press Release

Here it is:

https://news.lockheedmartin.com/2019...380.1545920007

This has X2 all over it and barely mentions the S-97. So this is basically Sikorsky saying forget the 97 with its high drag/low max speed, brutal vibration, and rotors that might chew themselves up in an abrupt maneuver and return to the promise of the (one step above a toy) X-2 for the FARA. Since the picture looks like a 97 but bigger, how is it not going to be even worse in all aspects?
The Sultan is offline  
Old 15th Oct 2019, 03:32
  #3 (permalink)  
 
Join Date: Feb 2015
Location: USA
Posts: 235
Received 45 Likes on 23 Posts
Originally Posted by The Sultan
Here it is:

https://news.lockheedmartin.com/2019...380.1545920007

This has X2 all over it and barely mentions the S-97. So this is basically Sikorsky saying forget the 97 with its high drag/low max speed, brutal vibration, and rotors that might chew themselves up in an abrupt maneuver and return to the promise of the (one step above a toy) X-2 for the FARA. Since the picture looks like a 97 but bigger, how is it not going to be even worse in all aspects?
That’s needlessly harsh... if they didn’t want us to think of S-97 Raider, their FARA CP wouldn’t be named Raider-X with a video full of Raider flight clips. That said, it’s still too many rotors and unnecessarily complex and expensive to meet the mission requirements. It is notable they never actually stated an MCP cruise speed and amount of payload at range and time on station. Just lots of promises of future growth potential... like it maybe needs a bigger engine now.
SplineDrive is offline  
Old 15th Oct 2019, 04:07
  #4 (permalink)  
 
Join Date: Dec 2000
Location: Arlington, Tx. US
Posts: 696
Likes: 0
Received 11 Likes on 7 Posts
SD

I didn’t right the press release. If they weren’t distancing they would have written 97 instead of X2. You of all should know that when battling excessive drag adding more power is a losing proposition relative to fuel consumption/range and in this case significantly higher vibratory levels/loads.
The Sultan is offline  
Old 15th Oct 2019, 04:55
  #5 (permalink)  
 
Join Date: Jun 2016
Location: Brantisvogan
Posts: 1,033
Received 57 Likes on 37 Posts
isn't CGI wonderful.
Bell_ringer is offline  
Old 15th Oct 2019, 14:42
  #6 (permalink)  
 
Join Date: Feb 2015
Location: USA
Posts: 235
Received 45 Likes on 23 Posts
Originally Posted by The Sultan
SD

... You of all should know that when battling excessive drag adding more power is a losing proposition relative to fuel consumption/range and in this case significantly higher vibratory levels/loads.
True, but adding more power to Raider-X will increase the top end speed and that appears to be what Sikorsky is selling, and they’re right in a way. With additional installed power, Raider-X can achieve speeds that the Model 360 cannot because the wing/rotor combination will cease to become an effective source of forward thrust long before the prop does. Of course, at the Army’s target cruise speed of 180 knots, this isn’t true, and a well designed single main rotor is sufficient.

The mass and cost penalty of a lift sharing wing and SPU is likely far less than an entire additional main rotor and controls, a high power clutched propellor, and the additional structure/systems required to sustain and mitigate the loads from the rigid rotors. In other words, the empty weight of Raider-X is bound to be higher than Model 360. Since the Army has requested a max gross weight and limited the rotor diameter, Sikorsky’s ship likely has less payload/fuel than the Model 360 at the customer requested max gross weight. To carry the full payload at the desired range, they’ll have to fly Raider-X at higher gross weights and disk loading which then incurs additional structural penalties unless they choose to have lower maneuver margins at those gross weights. Adding more power just compounds those issues.

Seems like a lot of downside for a little more speed.
SplineDrive is offline  
Old 15th Oct 2019, 18:05
  #7 (permalink)  
 
Join Date: Dec 2000
Location: Arlington, Tx. US
Posts: 696
Likes: 0
Received 11 Likes on 7 Posts
As stated elsewhere Bell took a two blade conventional Huey main an tail rotor compound to 274 knots. Shook like hell and had no range or payload. Sucks for S that physics doesn’t doesn’t change.

https://www.militaryfactory.com/airc...rcraft_id=1931
The Sultan is offline  
Old 15th Oct 2019, 22:40
  #8 (permalink)  
 
Join Date: Dec 2010
Location: USA
Posts: 237
Received 21 Likes on 17 Posts
Philosophies, Bell vs. Sikorsky

This is interesting.

It looks like Bell believes the Army will go for low risk and cost )and not give a ton of credit for performance much beyond the threshold and objective levels. They design for the cruise requirement and use the SPU to boost speed for the short dashes.

Sikorsky apparently believes the opposite.
Commando Cody is offline  
Old 15th Oct 2019, 22:51
  #9 (permalink)  
 
Join Date: Feb 2015
Location: USA
Posts: 235
Received 45 Likes on 23 Posts
Originally Posted by Commando Cody
This is interesting.

It looks like Bell believes the Army will go for low risk and cost )and not give a ton of credit for performance much beyond the threshold and objective levels. They design for the cruise requirement and use the SPU to boost speed for the short dashes.

Sikorsky apparently believes the opposite.
Speed isn’t the only metric to get credit on...
SplineDrive is offline  
Old 15th Oct 2019, 23:25
  #10 (permalink)  
 
Join Date: Dec 2000
Location: Arlington, Tx. US
Posts: 696
Likes: 0
Received 11 Likes on 7 Posts
CC

The FARA radius of action is only 125 miles so the tactical benefits of the Raider going 10% faster than the 360 are insignificant and not worth the complexity of an ABC over a conventional helicopter.
The Sultan is offline  
Old 15th Oct 2019, 23:46
  #11 (permalink)  
 
Join Date: Dec 2010
Location: USA
Posts: 237
Received 21 Likes on 17 Posts
Originally Posted by SplineDrive
Speed isn’t the only metric to get credit on...
Understood. I just used speed as an example of how these two contractors were looking at it differently. Bell going for low cost by not trying to do 205 knots for the entire flight. The basic question is overall how much credit will be given for how much performance. A bid could have better performance promises than another less expensive one, but if the extra credit given is not enough to overcome the difference in cost, it'll still lose. We've seen this happen in contracts awarded of the last decade or so.
Commando Cody is offline  
Old 16th Oct 2019, 00:13
  #12 (permalink)  
 
Join Date: Feb 2015
Location: USA
Posts: 235
Received 45 Likes on 23 Posts
Yes, there are more requirements than can all be met by a real aircraft, so the Army will have to evaluate each competitors performance and capability trade offs. Also, I doubt Raider-X can cruise at 205 knots... they only stated they think they can beat 205. Bet that’s a dash speed and not sustained MCP cruise speed.
SplineDrive is offline  
Old 16th Oct 2019, 12:57
  #13 (permalink)  
 
Join Date: Jun 2016
Location: Stagnation Point
Posts: 62
Likes: 0
Received 1 Like on 1 Post
Originally Posted by The Sultan
CC

The FARA radius of action is only 125 miles so the tactical benefits of the Raider going 10% faster than the 360 are insignificant and not worth the complexity of an ABC over a conventional helicopter.
Sultan (or other learned respondents)...

Thanks for the input on speed requirements.

Can you weigh in on the FARA life cycle cost requirements?

I have never seen a calculation, but I imagine LCC increase exponentially with speed. You raise the point that increased speed means little when applied over a short radius of action. So if you stack these two factors together, it indicates that the speed requirement is very costly... (nothing new here). Taking your point one step further, will the FARA increased speed requirement compared to conventional helicopters be similarly insignificant, i.e. will any operational benefit be realized given the complexities and uncertainties of the real world?

Increased speed incurs weight and/or fatigue life penalties, higher maintenance, lower Time Between Overhaul and others that don't come to mind immediately. Compared to current generation aircraft, these penalties will be somewhat ameliorated by health and usage monitoring and prediction.

Fuel consumption will also be increased, and this also presents at least a geometric if not exponential increased cost versus speed as you track it backwards in the supply chain (fuel burn by various modes of transportation from source to user). The fuel burn penalty due to speed is only there when you go fast, but the attendant fuel consumption due to increased weight is always present.

Fuel cost is one thing, but availability in a critical time of need is more important.

And of course none of the above touches on development and production cost deltas derived solely from speed.

Thanks,

DS
Droop Snoot is offline  
Old 25th Jan 2020, 20:52
  #14 (permalink)  
 
Join Date: Oct 2018
Location: nj
Posts: 29
Received 4 Likes on 2 Posts
One thing the Bell 360 does not have going for it is the fact it can't carry anyone. Neither could the OH-58 (well in a pinch). The Karem, AVX, and Sikorsky Raider (and possibly the Boeing XX-XX) all have what seem to be a 3-4 person cabin, but then again they use more advanced/expensive/intricate propulsion methods than the conventional-like tandem-seat B360. It makes you wonder if there will be a program to replace the MH-6 troop lifter... since FARA is to (more or less) replace the OH-58D.
Copter Appreciator00 is offline  
Old 25th Jan 2020, 22:16
  #15 (permalink)  
 
Join Date: Aug 2009
Location: Texas
Age: 64
Posts: 7,197
Received 394 Likes on 244 Posts
Originally Posted by The Sultan
SD
I didn’t right the press release.
And it's a good thing too, given how atrocious your writing skills are.
Thankfully, your paycheck is not governed by your communication skills, but rather your technical skills.

As to your points/criticisms on this PR release-I share most of them. (Bell Ringer's post made me chuckle).
This press release reminds me of the guy who thinks that foreplay is telling her how great of a time she's about to have.

For Spline Drive:
In other words, the empty weight of Raider-X is bound to be higher than Model 360. Since the Army has requested a max gross weight and limited the rotor diameter, Sikorsky’s ship likely has less payload/fuel than the Model 360 at the customer requested max gross weight. To carry the full payload at the desired range, they’ll have to fly Raider-X at higher gross weights and disk loading which then incurs additional structural penalties unless they choose to have lower maneuver margins at those gross weights. Adding more power just compounds those issues.

Seems like a lot of downside for a little more speed.
Thanks for that post. The Raider (S-97) as a follow up to what was achieved by X2 has intrigued me. Will it or won't it fulfill it's promise/potential? We simply don't know.

As to the Acquisition angle on this:
I am reminded of something from about 40 years ago, the infamous 'Hi-Low" mix for a Fighter program, which ended up with F-15 and F-16. And a by product of that was the F-18. Maybe, someone will finally accept a low risk, truly "low cost" for the Low in a proposal like this.
Not everything one buys needs to be bleeding edge. Cost is a variable in any acquisition decision.

But let's look at how deployable the FARA candidates are.
How many 360's fit into a C-17? How many Raiders?
What is the notional "self deployment" capability. (See V-280 for a comparison)

As one of you above said, Speed isn't the only metric.

Last edited by Lonewolf_50; 25th Jan 2020 at 22:26.
Lonewolf_50 is offline  
Old 26th Jan 2020, 03:53
  #16 (permalink)  
 
Join Date: Mar 2007
Location: Hobe Sound, Florida
Posts: 950
Received 33 Likes on 27 Posts
You know,LW,going down that road has just a few former SA folks asking why then didn’t SA simply ( airframe/drivetrain/rotors/power plant -wise ), simply update the RAH-66. Bell has to do development testing whereas the Comanche, aircraft wise, was developed.
JohnDixson is offline  
Old 26th Jan 2020, 14:07
  #17 (permalink)  
CTR
 
Join Date: Oct 2007
Location: Texas
Posts: 282
Likes: 0
Received 37 Likes on 20 Posts
The RAH-66 was a joint Sikorsky/Boeing program

Originally Posted by JohnDixson
You know,LW,going down that road has just a few former SA folks asking why then didn’t SA simply ( airframe/drivetrain/rotors/power plant -wise ), simply update the RAH-66. Bell has to do development testing whereas the Comanche, aircraft wise, was developed.
The RAH-66 was a joint Sikorsky/Boeing program. So Sikorsky would need to either re-team with Boeing, or Boeing would need to sign over the rights. Neither which are likely to occur. Especially after teaming on the SB>1 Defiant was not as amicable as what is portrayed in the press.
CTR is offline  
Old 26th Jan 2020, 14:59
  #18 (permalink)  
 
Join Date: Dec 2007
Location: Ireland
Posts: 396
Received 1 Like on 1 Post
Originally Posted by Copter Appreciator00
It makes you wonder if there will be a program to replace the MH-6 troop lifter... since FARA is to (more or less) replace the OH-58D.
The Boeing AH-6S Phoenix (Little Bird with 15 inch fuselage extension) would appear to be a very good candidate to replace the current Little Bird fleet if the 160th would rather stay with a traditional helicopter design. The extended fuselage would allow more room for additional fuel or perhaps even two additional seats in the rear cabin as well as the two external benches. Unfortunately the AH-6S never made it beyond the mock-up stage but with a new rotor, perhaps scaled down from the AH-64E Guardian (a possible consideration for the MELB if it is enhanced further beyond the Block III upgrade) it might be a slightly larger Little Bird with improved performance. Boeing haven't indicated any desire to resurrect the Phoenix project recently though.

I'm not sure being seated on a bench externally at FARA speeds would be appreciated by the bench-riders!

500 Fan.
500 Fan is offline  
Old 26th Jan 2020, 15:16
  #19 (permalink)  
 
Join Date: Feb 2015
Location: USA
Posts: 235
Received 45 Likes on 23 Posts
Originally Posted by CTR
Especially after teaming on the SB>1 Defiant was not as amicable as what is portrayed in the press.
This seems to be the consistent opinion on teaming with Boeing in the VTOL industry for the last several decades.
SplineDrive is offline  
Old 26th Jan 2020, 15:26
  #20 (permalink)  
 
Join Date: Feb 2015
Location: USA
Posts: 235
Received 45 Likes on 23 Posts
Originally Posted by JohnDixson
You know,LW,going down that road has just a few former SA folks asking why then didn’t SA simply ( airframe/drivetrain/rotors/power plant -wise ), simply update the RAH-66. Bell has to do development testing whereas the Comanche, aircraft wise, was developed.
I agree and I have heard the same comments. RAH-66 was a ~165 knot (cruise) machine and certainly with some more modern aerodynamics in the rotor, a drag clean up, small wing, etc. could be pushed to 180+ as Bell has done. Yes, it would be a clean sheet design and not a resubmission of RAH-66 due to the Boeing-Sikorsky teaming, but the knowledge base inside SAC to do so is still there, for now. Assuming an analysis of options was performed, I deeply suspect a strong X-2 "thumb" was placed on the scale. I think the company leadership is "all in" on the X-2 platform, even if it isn't the best match for the customer requirements.
SplineDrive is offline  


Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.