View Full Version : Pentagon moving ahead with new vertical lift aircraft
http://news.yahoo.com/pentagon-moving-ahead-vertical-lift-aircraft-044714179--sector.html;_ylt=A0LEVyxmaApTYhwAYX1XNyoA;_ylu=X3oDMTEzaTg0a2U4BHNlYwNzcgRwb3MDMgRjb2xvA2JmMQR2dGlkA1NNRTQyMV8x?.tsrc=samsungwn%3Fdate20120217%3Fdate20120305%3Fdate20120315
"Ultimately, the program will replace between 2,000-4,000 medium class UH-60 Black Hawk utility helicopters built by Sikorsky Aircraft, a unit of United Technologies Corp and Boeing Co AH-64 attack helicopters after 2030...The Army is focused heavily on getting affordable aircraft that will be cheaper and easier to maintain than current helicopters."
What could something like what they are asking for could possibly look like?
I'm going to say it's one of three things:
-- another helo (BTW, why are they all limited to around 200 mph?)
-- an Osprey knock-off/upgrade/type system
-- something Harrier-ish.
Really, with where our technology is currently, I can't think of anything that would replace either of those as vertical lift. Unless we go back to the thirties with that crazy gyroplane.
Don Robison
02-23-14, 20:26
-- another helo (BTW, why are they all limited to around 200 mph?)
Dissymmetry of lift. The retreating blade will lose lift at some point above VNE (do not exceed speed) causing retreating blade stall(lose lift) which causes the nose to pitch up and the retreating blade side to roll down.
On the new design they are looking for, who knows, there is always room for improvement above current designs. Helos are expensive to operate and more costly once all of the new design avionics are installed.
RogerinTPA
02-23-14, 23:26
Dissymmetry of lift. The retreating blade will lose lift at some point above VNE (do not exceed speed) causing retreating blade stall(lose lift) which causes the nose to pitch up and the retreating blade side to roll down.
On the new design they are looking for, who knows, there is always room for improvement above current designs. Helos are expensive to operate and more costly once all of the new design avionics are installed.
Actually it's called 'retreating blade stall' for the main rotor, and the forward airspeed has always been limited to the characteristics of the tail rotor operating at such a high speed, which will cause it to stall as well. Unless they go with a NOTAR (No Tail rotor) or shrouded impeller as used on the coast guard dauphins and the scraped army comanche.
OP: They are much better off going with a tilt rotor design, or a jet version of it. The first variation of a jet with nacelles that tilted was back in the 60's, which wasn't to successful, given they were captured by the technology of the day. Helicopters will always be expensive due to a given payload & fuel carried, the over all max gross weight and wild temperature extremes. If they want a helo that can actually do something, it's going to be expensive.
Anything approaching USAF territory, they will scream bloody murder, demand to adopt that concept to provide the US Army airlift and CAS support, then kill the program like they always do.
Don Robison
02-24-14, 00:22
Actually it's called 'retreating blade stall' for the main rotor, and the forward airspeed has always been limited to the characteristics of the tail rotor operating at such a high speed, which will cause it to stall as well. Unless they go with a NOTAR (No Tail rotor) or shrouded impeller as used on the coast guard dauphins and the scraped army comanche.
OP: They are much better off going with a tilt rotor design, or a jet version of it. The first variation of a jet with nacelles that tilted was back in the 60's, which wasn't to successful, given they were captured by the technology of the day. Helicopters will always be expensive due to a given payload & fuel carried, the over all max gross weight and wild temperature extremes. If they want a helo that can actually do something, it's going to be expensive.
Anything approaching USAF territory, they will scream bloody murder, demand to adopt that concept to provide the US Army airlift and CAS support, then kill the program like they always do.
True, I was in a hurry, and left off the tail rotor also playing into the equation.
I'm going to say it's one of three things:
-- another helo (BTW, why are they all limited to around 200 mph?)
-- an Osprey knock-off/upgrade/type system
-- something Harrier-ish.
Really, with where our technology is currently, I can't think of anything that would replace either of those as vertical lift. Unless we go back to the thirties with that crazy gyroplane.
Nor can I, and those last two possibilities seem like they would be both more expensive and more complicated to maintain, while it also seems to me that the first possibility, another helo that is "cheaper and easier to maintain", means a helo with less capabilities.
Actually it's called 'retreating blade stall' for the main rotor, and the forward airspeed has always been limited to the characteristics of the tail rotor operating at such a high speed, which will cause it to stall as well. Unless they go with a NOTAR (No Tail rotor) or shrouded impeller as used on the coast guard dauphins and the scraped army comanche.
OP: They are much better off going with a tilt rotor design, or a jet version of it. The first variation of a jet with nacelles that tilted was back in the 60's, which wasn't to successful, given they were captured by the technology of the day. Helicopters will always be expensive due to a given payload & fuel carried, the over all max gross weight and wild temperature extremes. If they want a helo that can actually do something, it's going to be expensive.
Anything approaching USAF territory, they will scream bloody murder, demand to adopt that concept to provide the US Army airlift and CAS support, then kill the program like they always do.
Perhaps the thinking going forward on this is something along the lines of this?
http://i.kinja-img.com/gawker-media/image/upload/t_k-bigpic/18s0a88idqqh1jpg.jpg
Perhaps the thinking going forward on this is something along the lines of this?
http://i.kinja-img.com/gawker-media/image/upload/t_k-bigpic/18s0a88idqqh1jpg.jpg
That would be cool...
http://www.wired.com/autopia/2010/08/sikorsky-x2-breaks-helicopter-speed-record/
Will there be enough pilots to fly these some 2 or 3k aircraft once Hagel chops the Army down to pre-ww2 levels??
Even during the last 11 yrs the Army has had more pilots then Aircraft.
Is this more wasteful spending by our DoD??
Sent from my iPhone using Tapatalk
Keep in mind the Army will continue to be the most modern army in the world. This is an investment in the future.
The plan is to kill older systems and replace them. Now, if they want to reform the broken procurement process then that is another discussion all together.
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Outlander Systems
02-24-14, 12:18
High-efficiency quadcopter personnel and materiel transport would be righteous.
The biggest obstacle for this would be efficiency. Quad-copters suck power.
Perhaps the thinking going forward on this is something along the lines of this?
http://i.kinja-img.com/gawker-media/image/upload/t_k-bigpic/18s0a88idqqh1jpg.jpg
Updated version of a Ka-50...
RogerinTPA
02-24-14, 17:39
Perhaps the thinking going forward on this is something along the lines of this?
http://i.kinja-img.com/gawker-media/image/upload/t_k-bigpic/18s0a88idqqh1jpg.jpg
A pusher dual counter rotating main rotor hybrid would be the way to go, no doubt. Variations of the concept has been done before in Lockheeds RAH-54 Cheyenne, which had both a tail rotor and a pusher prop. http://www.militaryfactory.com/imageviewer/ac/pic-detail.asp?aircraft_id=258&sCurrentPic=pic3
The russians have been using a similiar dual rotor helo for quite a while, with the Ka-52 Alligator, being the latest rendition.
https://www.youtube.com/watch?v=t3O801sVuVo
Knowing that it's russian, and from a pilot perspective, I certainly wouldn't count on the ejection seat portion working. Correction, the seat might work, but the main rotor separation when needed, would be the greatest concern, especially if I was flying it.
It makes sense to blend the two technologies, as in the S-97.
http://www.military.com/video/aircraft/helicopters/the-s-97-next-gen-attack-helicopter/2577282846001/
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