V-22 Osprey Tiltrotor

I think if the Osprey was to be used in the CSAR role, it would be in a more "cooperative" way. That is, it wouldn't be a solo mission, more of a team...the V-22, armed escorts, maybe CAP and a FAC as well. Kinda like the old Jolly Green/Skyraider teams I've read about. Too often people look for the "all-in-one" answer to the problem and you don't get what you really need, but a collection of compromises and concessions that instead of doing one or two things really well does everything really poorly.

WARNING: The following comment and question is based on NO ACTUAL SAR experience, but info gleaned from this and several other forums, news reports and being a fan of USCG ops. Got it? I admit up front, I don't know what I'm talking about!!!!

Triggger: If rotor wash is a big problem with the Osprey enough to cause brown outs and what not, as reported, wouldn't it also hinder USCG SAR actvities? I'm thinking if it causes a brown out, then it would stir up water enough to cause similar issues and prevent rescue swimmers from doing their thing.

Sorry Grant, but I had to chime in...

From a USAF perspective, the powers that be see the aquisition of the CV-22 as a replacement for both the Pave Low and MC-130P tankers. Personally I don't agree and am of the opinion of many other members of this forum. Considering Special Ops, I don't see where you're improving things when you have little self-protection armament. Yes, there are many other self protection measures (RAW gear, IR supressions, etc..) however do YOU want to put all your eggs in that basket? As a guy who works out of them, I know I sure as hell don't. Now someone in this post said that we'll go back to the big package CSAR like we did in Vietnam. As a USAF CSAR guy, that's not feasible. You don't want to increase assets for a CSAR package rather lessen them. Hell, I love Sandy's and the RESCORT they provide for us (A-10's or otherwise), but I will say as a guy who un-asses the Helo and snags the survivor, I also don't like a couple A-10's orbiting around the survivors position highlighting it for the bad guys. It's a dual edge sword. The best CSAR missions are when we go in, score a touchdown and nobody knew we were there. More assets on scene mean more potential survivors. So the big CSARTF is out.

Is the V-22 pretty much a given for the US DOD.....Yep

Is it expensive.....yep

Has there been lot's of problems in the OT&E...yep

Are the Phrogs and Pave Lows reeeaaallllyyyyy old and need to be replaced...yep

I'm just not sure what the most effective application is going to be. I can only speak from a CSAR perspective and say that it's not in my line of work. We need a new HELICOPTER and newer H/MC-130's. The vulnerability I see as a package of V-22's comes to a hover in a hostile LZ doesn't give me a warm fuzzy and I see the need for a bunch of other assets being necessary.

Just my 2 cents worth.

Sal,
Guess I was thinking as an old Marine 0311, we tend toward the "kick in the door, and bring all the guns you can to the fight" mentality. You make great points about not drawing attention to the CSAR guys while they do their thing. I just was throwing ideas out there as to how the V-22 could possibly do the job, but it would need an escort until the armament question can be addressed.

I really appreciate your insights, Sal, as one who does the job, you give the rest of us a better idea of what really goes on. Thanks.

LemonJello,
I here ya....as an ex-11B I agree with you to a certain extent. I just can't warm up to the V-22 as a do all/replace many airframe. "Jack of all trades, specialist in none"
I remember working with a USMC "Big Iron" driver back in 97 during a JTFEX. During one of those long mission planning nights we got to BSing about the V-22. He said that he and many other -53 drivers wanted nothing to do with it. Now I'm sure that there are many that want to get into the new airframe (there always are), but that's what was the sentiment as he expressed it.

As far as chiming in on stuff, same goes for you brother. I count on you and many others on this forum to chime in with insight based on your background an operational experiences.

Maybe we just need to leave the Osprey alone with the mission it was designed for, which is the ability to take-off and land like a helo, but has the speed and range of a transport.
Maybe we should crank up the old production lines and make new 46's and 53's. Same basic design but more modern features(composites, avonics, engines, etc.)

Yeah guess they could be used as a transport vehicle if they cant use it for any kind of firefight situations.They've spent too much money on it to just let it go now.

I have a patent pending on a design far superior to the V-22.

To do the same mission? Is it something you can share?

Phil

Yeah, you can't say you've got a better mousetrap and not share something. You can't tease us on something like that. What is it, an actual working Drop Ship from Aliens?

The last I heard the FAA was going to certify the aircraft in a seperate catagory. My experence with the Tiltrotor (XV-15) was in a support role at NASA Ames. An interesting machine to be sure. Bell had originally proposed using an AH1S airframe as a prof of concept demo machine but went with the XV-15 instead. There used to be a mag out called "Aerophile" which ran an article on the proposals and on the tiltrotor's final configurationas XV-15. Anyway if you can find a copy it would be interesting reading to augment the Norton book .

Regards to all.

I'll get some materials together and post them. My concept is called the Rotorjet and is ridiculously simple and balanced ... using several existing technologies simply arranged in a new way. All proven, mature systems. And it has a broader range of applications than even helicopters have, from drones and UAVs to transport, heavy lift, rescue or attack, all at higher speeds. It's been reviewed and the concept endorsed by Sergei Sikorsy and the head of DARPA. I'll post something by tomorrow ...

QUOTE: Originally posted by DYNOSOAR Bell had originally proposed using an AH1S airframe as a prof of concept demo machine but went with the XV-15 instead. There used to be a mag out called "Aerophile" which ran an article on the proposals and on the tiltrotor's final configurationas XV-15. Anyway if you can find a copy it would be interesting reading to augment the Norton book .

Some of the Bell's conceptual tiltrotor designs can be found at the AIAA website.

http://www.aiaa.org/tc/vstol/unbuilt/bell_tlt/index3.html

Some neat configurations.

Phil

Wow! Those don't look too far off from my AV-15. Biggest difference is the tandem cockpit.

Is that some sort of jet powered autogyro or coaxial?

It's a NICE illustration - who did it?

I did it ... that's my Rotorjet concept. You are close ... the rotorhead is coaxial and driven by the jet engine N2 turbine stage. It's an axial-flow jet, not anular flow like jet turbine helicopters, so it produces plenty of thrust. To hover, however, the tail cone slides back and blocks the thrust, also exposing cascades on either side that vector it at 90 degrees right and left, canceling the thrust effect. Movable vents within the cascades vary the side thrust enough to turn the fuselage as needed.
Too damn simple, isn't it?

Very cool, not that I understand all (or any, for that matter) of the techno-talk about it. I can see the attack/escort possibilities from your picture, would it be scalable up to heavy lift and troop transport? Would that require additional rotors and engines?

You mean like this?

Neat design

QUOTE: Originally posted by MBT70 I did it ... that's my Rotorjet concept. You are close ... the rotorhead is coaxial and driven by the jet engine N2 turbine stage. It's an axial-flow jet, not anular flow like jet turbine helicopters, so it produces plenty of thrust. To hover, however, the tail cone slides back and blocks the thrust, also exposing cascades on either side that vector it at 90 degrees right and left, canceling the thrust effect. Movable vents within the cascades vary the side thrust enough to turn the fuselage as needed. Too damn simple, isn't it?

Holy crap, I actually understood most of that, and I'm not an engineer (I suck at math so I changed majors)! I'll have to look up a couple of things tonight when I get home, but yeah, that seems pretty simple.

That's a SWEET illustration. I'd like to see some more and discuss the techniques and materials you illustrate with. Shoot me an e-mail?

QUOTE: Originally posted by rockythegoat Trigger: If rotor wash is a big problem with the Osprey enough to cause brown outs and what not, as reported, wouldn't it also hinder USCG SAR actvities? I'm thinking if it causes a brown out, then it would stir up water enough to cause similar issues and prevent rescue swimmers from doing their thing.

I think what they do now is, the swimmer goes out the door and then the helo pulls back for that very reason. A tilt rotor would have to do the same.

TRIGGER: The condition you refer to as a brown out is common to all helicopters operated in a dust/dirt filled environment. the solution we found in Viet Nam was to shoot the final approach to the ground, instead of to a hover. It worked out pretty well, plus it had the advantage of providing some modicum of obscuration for assulting troops to dismount our Hueys.

MBT70: Nice design! Looks awsome..however a similar "hot" rotor system as you are proposing was tried on the Sikorsky "X-Wing" and was too complicated to maintain (rotor seals/slip rings were the culprit), they also tried a coaxial helicopter known as the "ABC" (Advancing Blade Concept) in competition to the Bell XV-15 and lost out. Your design looks good! Too bad you weren't around for LHX....

MBT70
I agree with the others, really great illustration. Interesting concept. Even though it appears to be simple, I've worked on these kinds of things in the past, and it always works out that the devil is in the details. I'm not sure how much speed can be achieved simply because a coaxial rotor system creates plenty of drag. I'm not sure what the state-of-the-art is in stability of high speed rotors, I'd have to do a little research. I don't think it's a simple problem though.

Phil

The aircraft still has to maintain a hover anytime you're doing hoist ops, FRIES or rappeling. Helocasting is great, but you still need to recover the SAR swimmer.
A while back I spoke to several STS members who (for the USAF) were involved with the OT&E on the V-22. These are guys who've operated out of Hawks, Hueys, Chinooks (probably the worst I've ever dealt with concerning rotorwash). and -53's. These guys said the V-22's rotorwash was the worst they'd ever dealt with. Damn near couldn't stand upright when underneath. Besides, where are you going to mount the hoist?

Now show me a rotorcraft that doesn't produce rotorwash, and I'll give you a dollar. And yeah I've seen lots of brownouts, and whiteouts both here in Alaska and deployed, but for an aircraft that's assuming a mission requiring operators to conduct operations from a hover on a regular basis.....extremely powerful rotorwash is not good.

I've never been under the rotor wash of anything bigger than a B-412 so my comment about how a tilt-rotor would operate in a maritime rescue situation is based on watching video of Jayhawks and Dolphins conducting pickups.

Hmmm.... Chinooks have bad rotorwash too? Anyone here spent any time under a -46; how's that rotorwash? I'm wondering if the Osprey's rotorwash problem is a problem with the Osprey itself or something that happens with an airframe that has two rotor discs.

Rescue hoist, defensive armament, rotorwash, FRIES... was any of that taken into consideration two decades ago?

This isn't a hot rotor, it's a conventional coaxial system like the Russians use a thousand times a day, although it does have some ABS innovations. Sikorsky's ABS testbed used separate, external engines for forward thrust, adding complexity and weight, not to mention fuel consumption. The Rotorjet has the same kind of two-function turbine as a high-bypass turbofan, but the shaft that would drive the big fan drives the rotor instead. And the speed would be decidedly subsonic, due to rotorhead drag, but much faster than Osprey. And much simpler. Fewer moving parts, closer together and balanced in every quadrant around the CG. Sergei had some very good things to say about it. He recommended that the rotor be a low-profile, elastomeric type with a flat chord to reduce drag at higher speeds. And he agreed with me that pitch should be minimal above normal rotary-wing speeds to reduce drag and allow the wings to dominate flight control instead of cyclic and collective, which would be the primary control at low speeds and hover.

Here's a great rotorwash story ...

In '69 in Phan Thiet we were hoisting a wounded soldier out of a jungle clearing too small too land in and i was part of the security force surrounding the site. The Huey took very little time getting the litter out and I was standing with my back to it as the rotorwash buffeted everything around. About then, I hocked a big loogie and the rotorwash caught it and carried it hundreds of feet out before it fell to the ground in the trees. I think I set a world record for flipping a lunger.

Thus inspiring challengers to the throne to hock loogs across the land. Just make sure y'all don't spit against the wash.

Trigger
I haven't spent any time under a 46 but I was dumb enough to tell some Chinook guys that I would stay and do some hook-ups for them. We had been doing some sling load training on some guys and I drew the short straw. When the 47's showed up I figured that it couldn't be that bad. If they don't make a decent approach it can be pretty rough but all I ever really needed to do was take a knee as they came in. The only really bad part was when the dumb driver cracked my helmet when I got up to do the hook up.

Mac