Forum: Rotary Wing Aircraft

Article from FlightGlobal.com here. Whatever they end up deciding upon...it'll be BIG!

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Forum Veteran Joined: Dec 15, 2006 - 12:28 AM Posts: 760

I am somewhat skeptical and sarcastic if this is a good idea. Perhaps we should get more time and experience with the V-22 before we are so eager to develop such a project.

I'm sure that the troops really need such a vehicle, however at this point in time I really question the wisdom of sending something to the front lines that is so expensive and complex that is such a big slow-moving juicy target for an enemy.

Maybe the US Army should buy a few of these. A few hundred million on a bit of an upgrade to the design. I am certain the Russians would love the trade dollars.
http://blogs.crikey.com.au/planetalking ... -aviation/
Photos of a Chinook being rescued by a MI -26 in Afghanistan. Photo by John Roberts

I hope the Army really thinks this one through. I think they have bigger issues within their own aviation community to worry about.

You would be a lot simpler going for a STOL transport built around huge turbofans with the Rolls-Royce shaft-driven Lift System of the F-35B program, only driving larger diameter lift fans. Its a lot easier to tilt nozzles than it is to tilt rotors. You would be looking at an engine with roughly 60,000 lb st of dry thrust. And there are plenty of turbofans in the 60,000-70,000 lb range to fill the role of driving the lift fans. Two high-mount over-wing engines and one tail-mounted engine should be plenty for a C-130J-sized aircraft. Give it four engines if you want something more akin to the A400M.

The engineering behind the V-22 both marvels me and gives me the creeps. The complexity is a nightmare and will prove accident prone the more its used.

What makes a heavy-lift powered gyro-copter improbable? The 105-ft long Mi-26 rotor is smaller than each of the rotors on the Mi-12. The latter actually outweighed the C-130J at maximum takeoff and carried a heavier maximum payload! Use two large rotors like the Mi-12 did, but use a bi-plane wing arrangement for maintaining lift during forward flight. That way you can cut down dramatically on the amount of power you have to send to the gyro-rotors during flight. I don't see the real need to haul heavy tanks in VTOL-style. The gyro-copter layout gives you a simpler STOL approach that has proven to be very safe in the civilian world. Think about it, if you happen to lose the power drive to the rotors a gyro-copter is still extremely forgiving while landing. Give it a bunch of wheels to land on (but less than 32 wheels of the An-225) and you can land on wet dirt conditions that a C-17 would just as soon avoid.

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You would be a lot simpler going for a STOL transport built around huge turbofans with the Rolls-Royce shaft-driven Lift System of the F-35B program, only driving larger diameter lift fans.

The Army is. It's called the C-27J Spartan. They've already taken delivery of a few as far as I know.

http://www.flightglobal.com/articles/20 ... -army.html

We arent getting the Spartan, at least we arent getting it in the operational capacity your thinking. They have a limited handful for use by groups like Flight Concepts and the Aero Testing group down here at Rucker but the total of the Program has been turned over to the Air Force last year by General Cody. Rumor was we were going to pick up a large chunk of the Operations the MC-12 is doing for them but that looks like nothing but rumint.

And Madrat, how many succesful deployments of the Osprey is it going to take before people like you get over your irrational fear of that Aircraft? I wanna say the Marines are on their 4th or 5th Deployment of it at this point and the only crash so far has been by an Air Force CV-22 whose pilot went inadvertant IMC at low alt and hit a mountain.

Wow, 5 deployments is the point where we stop worrying about an accident prone program? I don't think that is prudent.

"Accident Prone"

Apparently having fewer Class A accidents per operational flight hour in the same theatre of ops than the aircraft it replaces makes it that way huh.

How about this, your fears are unfounded and that aircraft is far safer in our current operational profile than any other rotary winged platform.

If you treat a machine kindly it will last longer and have fewer accidents. Problem is you're sending these machines into war zones and they weren't meant to be treated kindly. Unfortunately that is your operational profile, keep it nice and gentle so you don't fark them up. The program should have been axed a long time ago. Its an expensive toy when we need more fiscal responsibility to develop more prudent programs.

Im guessing your not a helicopter pilot are you. I can tell you both my personal and others opinions on the matter, we would kill to be able to engineer some of the capabilities that the Osprey has into our aircraft if it were possible. It isnt.

The V-22 has single engine capability in Afganistan.... No helicopter in theatre does unless its flying with no load and very little fuel. If I lose an Engine (or a Hawk, Phrog, Chinook, Etc) at those altitudes unless Im running on empty and on my way back to the FARP I cant maintain level flight on my single good engine. Regular helicopters also are not capable of arresting the decent rates the V22 can because it has gobs and gobs of power available. That means we are far more likely to get ourselves into a settling with power situation than they are. It has one of the most reliable and redundent hydraulic systems ever put into an aircraft and maintain contol if they fail. I fly a helicopter where if the Hyd go, I cease to be a non voting member in the aircraft control council and Im supposed to be shot at so thats real f'ing comforting.

The Black Hawk used to have serious issues with the stabilator having uncommanded scheduling to full down at airspeed causing the aircraft to nose over into the trees. We lost a lot of them that way... Its currently the worlds best Medium lift Utility Helicopter. The Harrier has lost almost 1/3 of the original buy order by the Marines over its service time.... They are still operating without people screaming about it killing Marines.

So besides your opinion on the matter what facts do you have to bring into this discussion. Or are you just one of those people that likes to bitch about new programs without having any experiance or knowledge to base the arguement on?

Elite 1K Joined: May 26, 2005 - 08:39 PM Posts: 1496

I agree with Lawman, 100%. Yes, the V-22 is new technology, yes it's different. But it hasn't had any mechanical related fatalities in 10 years. There is some risk in developing new platforms. Hell, a prototype F-16 had to be ditched landing gear up, and even the F-22 was bounced off the concrete in the early days. And rotary Back in 2000 when flight testing was underway should there have been 20 Marines stuck in the back of the aircraft instead of 20 Marine shaped sandbags? Probably not. But that's not the fault of the design. The reason they DO flight testing is to explore the flight envelope and VRS jumped up and bit them in the a$$.

In the Marine Corps the V-22 is the replacement for the CH-46. New H-46 airframes haven't been built since 1971. The Marines put their chips fully behind the Osprey program and now have the first operational tilt rotor aircraft in the world. Yes, it's more expensive than a traditional helicopter. But it also has a larger combat radius and a much higher cruise speed, which the Marines badly wanted for their over the horizon amphibious assault capability.

Guysmiley said, "But it hasn't had any mechanical related fatalities in 10 years."

'Mechanical related' is a technicality. But people continue to die disproportionately to using the V-22 than the helicopters it was meant to replace.

Elite 1K Joined: May 26, 2005 - 08:39 PM Posts: 1496

madrat wrote:

Guysmiley said, "But it hasn't had any mechanical related fatalities in 10 years."

'Mechanical related' is a technicality. But people continue to die disproportionately to using the V-22 than the helicopters it was meant to replace.

That statement is disingenuous at best and an outright lie at worst. There was a CFIT mishap in April with a USAF CV-22, as in "pilot flew into terrain". Before that the last fatal accident was in 2000 while undergoing flight testing and I guess TECHNICALLY even that mishap wasn't a mechanical failure, it was due to settling with power, or vortex ring state.

madrat wrote:

Guysmiley said, "But it hasn't had any mechanical related fatalities in 10 years."

'Mechanical related' is a technicality. But people continue to die disproportionately to using the V-22 than the helicopters it was meant to replace.

Now your either being ignorant or just lying/making sh*t up, neither of which is acceptable.

The CH46 had 53 Fatalities from 1995-2005. It had 20 Class A crashes in the same time frame. It had 44 in the first 5 years it came into service after 1962. So yeah the V22 is safer. Not to mention the V22 is far more survivable in a crash since it actually has crash seats in the back for the passangers instead of just the aircrew. They will absorb a 26 G impact between the airframe and seat engineering before transfering any of that impact force into the spine of the passanger. Thats way way above the 10 Gs your expected to die at in the 46. Not to mention that in a crash the back end of the 46 has a tendency to collapse under the weight of the engines and transmission and enter the crew cabin crushing the rear occupants.

Forum: Rotary Wing Aircraft

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