V-22 Osprey Info

[46Driver]

If you are on the edge of the envelope and for whatever reason (crosswind, turbulence, etc) one side gets dirty air and the other has clean, then you enter differential VRS. That leads to how soon the pilot detects power settling (we just had an experienced JetRanger instructor spread the skids here because he didn't recognize it). If the pilot does NOT recognize the situation and mistakenly adds power, then the bad air side sinks while the good air side climbs - and the Osprey flips.

For an example of twin rotor configurations producing differing results, the CH-46E NATOPS states that when entering retreating blade stall you don't know which way the Phrog will roll because you don't know whether the front or aft rotor system will stall first.

You are absolutely correct about a C-130 pilot being at the controls of the dash-2 Osprey in AZ - I floated with both of the pilots of the lead Osprey and they were both outstanding pilots.

I also have doubts about the Osprey being able to land (not fly) at high altitudes (10,000 ft) due to the high blade loading of the prop-rotors. At any rate, it was a fun simulator to fly.

 

[bugchaser]

I'm no expert but I do get to watch them fly regularily here at our local airport. Kind of neat to share the pattern with an Osprey while doing touch and go's with a student. Looks like it performs pretty good to me. Makes one hell of a runway sweeper!

 

[HueyPilot]

V-22 debate

I'm gonna disagree on this one. The side by side prop-rotor configuration is going to lead to a lot of trouble on the vortex ring state. Unlike single rotor or tandem rotors, I can certainly see situations developing where one side of the V-22 goes into VRS, the other side doesn't, the pilot mistakenly adds power, and the aircraft flips over.

If that's your arguement saying the V-22 is unsafe, then every airplane out there is unsafe.

Get an airplane close to stall speed, kick in some rudder, and you'll stall one wing before the other one...and a spinnin' you'll go...and it's pretty much unrecoverable at low altitude.

 

[skiddriver]

First, I'm glad you guys are considering what is going on with this aircraft because you'll be flying it for a long time.

I was the senior test pilot in the Cobra shop at Pax during my follow-on tour from NTPS. One of my classmates was the primary V-22 test government pilot at Pax for over 4 years (involuntarily extended despite his desire to get to the fleet) and was supposed to be one of the first squadron CO's prior to the New River crash. We compared notes on the V-22 test progress throughout his stay there. I flew chase on the aircraft and sat in on way to many V-22 test plan review boards as the acting CTP. I point these things out as a way to say that I know a little bit of what I'm talking about.

The design problems which resulted in the majority of the fatal crashes should have been caught, but the complexity of designing a new aircraft makes that difficult. In particular, the software problems that lead to the New River crash managed to make it through years of testing before they killed that crew.

I hate discussing accidents that can be termed pilot error, and I'm sure your shipmate was a good pilot, but the answer to overshooting a zone isn't to enter a 2000+ FPM ROD below the established VRS airspeed limit.

The differential VRS argument is a lot like many of the arguments about the V-22. What do you think would happen in a 46 if you entered a several thousand FPM vertical descent and then yanked in a bunch of collective? My Dad had the rear rotor shot off his 46 by an RPG during a recon extract off a hilltop in Vietnam (they survived). How well do you think it flew then? One online quote I've seen said that if you put the V-22 in a hover and then yanked the thrust levers to zero, it would enterd a 3000 FPM ROD in a few swconds, and used that as an argument that the aircraft was unsafe. What would happen if you put an AH-1W in a hover and slammed the collective down to the flat pitch setting? Does that make the AH-1W unsafe?

The real problem with the V-22 is going to be found in maintainability and reliability, and because of the tight clearances on board ship, I forsee the day that some young ham fist is going to have some ship structure-proprotor interaction.

Fly the aircraft in the envelope and it's will perform as advertised (mostly).

Good luck and keep thinking about this stuff. It can help keep you from getting killed. Also, don't be afraid to call the test shop at Pax. We always enjoyed getting inquires from the fleet, it kept us on our toes.

Edit:

One other point that I should have made. Anytime someone makes a positive or negative claim about an aircraft or system, we should try and apply a little critical thinking. Who are they and why are they putting the info out there? Some of the biggest opponents of the V-22 and UH-1Y programs are the Army and Navy H-60 PMA's. They have actively campaigned to put holes in these programs to force the Marine Corps to buy H-60's and keep the 60 production line open. They like the H-60 and want the production line open for follow-on buys. They don't give a rat's butt about the Marine Corps or our requirements.

Sikorsky helicopters, in particular, has had 3 different aircraft systems in play as V-22 replacements, and you will regularly see disinformation passed around by their representatives and employees, past and present. They aren't doing it out of a purely altruistic desire to provide the best system for the Marine Corps, they want to sell helicopters.

Same thing with the AH-1Z program. The Apache mafia actively campaigned with foreign governments looking to buy attack helicopters (that is active duty Army personnel lobbied foreign governments - British and Dutch) to promote the Longbow and provided data that they said proved that the Cobra was unsafe. Why? To keep the production line open and drive down the Army's unit cost.

I had the head of Army aviation acquisition ask me why we didn't just buy the Longbow instead of upgrading the Cobra? I countered by asking if the Army was willing to help pay the estimated 5-10 mil cost (per airframe) to redesign the Apache for shipboard use, on top of the 15 mil per airframe cost, plus the squadron retool and add-on GSE cost. He got very quiet.

The biggest oppenents of the Army's Comanche? The Army's Apache crowd. They boasted to me in an informal meeting that they were going to "kill the Comanche program and take their money."

The list goes on.

That is not to say that there aren't well-informed and well-intentioned folks who question the wisdom of program expense, or the safety of systems, solely from a sense of concern for our servicepeople or concern over public expenditure. There are. It's just that it is difficult to weed out their arguements from the sharks who are looking to nab other program's funds to cover their expenses. It is even harder to tell where the well-intentioned folks got their data.

The spinning of data by all sides (pro and con) is another topic all together.

So I'll end by saying that when someone says "if you do this with an XYZ aircraft, that will happen, causing a fatal accident," you should ask yourself, "if I do the same thing with another, similar aircraft, what will happen?" and "why is this person saying this anyway, what do they stand to gain?"

Also, if you have to choose among opinions, just remember the sign we had in our office at Pax River. "Never trust an engineer, they tend to blurt out the truth under pressure."

If you have a question call one of the engineers or engineering test pilots at Pax, they'll answer it for you if they can.

 

[MJG]

Couple more questions.

What happened in the New River accident, someone mentioned a software bug?

Also how many total accidents, fatal and non-fatal, has the V-22 program suffered? And how does this accident rate per test hours compare with the Harrier program when it went through its growing pains?

 

[skiddriver]

Couple more questions.

What happened in the New River accident, someone mentioned a software bug?

Also how many total accidents, fatal and non-fatal, has the V-22 program suffered? And how does this accident rate per test hours compare with the Harrier program when it went through its growing pains?

Sorry, can't answer either question. The first because I had access to privileged accident board material and don't have the report to censor my response beyond what I said earlier. The second because I don't have those figures, though they should be available on line.

 

[46Driver]

I'll second what skiddriver said about accident. I didn't see the report but the Corps is so small I can't remember if what I heard was privileged or not. Try a google search.

My problem with the Osprey is not over its safety - every aircraft will have problems when flown outside its envelope - but the cost of the program and the limited missions. If the V-22 could have been purchased a decade ago at the price quoted, then maybe it was a good idea. Now, with the price going through the roof, I think there are better alternatives. I wrote on the V-22 as a prime example of waste in my acceptence paper for the Naval War College. In talking to engineers, specifically those at Piasecki who are working on the Vectored Thrust Ducted Propellor modifications, I believe the compound helo is a much more cost effective alternative to the tilt-rotor concept.

 

[Michael Knight]

Selection into this program has been rumored for the last 10 years. Yes, they did select some right out of flight school a few years ago and they never made it to the cockpit since the program had so many setbacks with the highly qualified fleet experienced crews that were initially assigned. No blame to those initial crews, the aircraft was/is still in its proving phase with so many aircraft problems. If I were a flight student I would do anything to avoid selection into the 22 program. It is going to be a painful program for many years to come. Personally I think the Corps should have abandoned the 22 program years ago and followed the Army's lead with regards to helicopter purchases. I think the Corps will stick with it instead of admitting it was a mistake... kind of like the Harrier program, but that is another subject in itself.