V-22 Training Question

[gator274]

Just wondering what the training pipeline is going to be for tilt-rotor pilots. I'm sure that it will include a full stint at NAS Whiting Field with the TH-57 but how much multi-engine fixed wing time will it include?

 

Also, if you lose an engine while operating in plane mode how much performance do you lose. Those huge props must be akin to large anchors especially before being feathered?

Edited December 27, 2007 by gator274

[IFLY]

I talked to some of the pilots at an airshow and they said they had better luck with nonpilots. Heli pilots had the hardest time converting.

The engines are connected to both props so you land in airplane mode, no feathering. Let me know if I'm wrong.

 

Jerry

[Rob Lyman]

Just wondering what the training pipeline is going to be for tilt-rotor pilots. I'm sure that it will include a full stint at NAS Whiting Field with the TH-57 but how much multi-engine fixed wing time will it include?

 

Also, if you lose an engine while operating in plane mode how much performance do you lose. Those huge props must be akin to large anchors especially before being feathered?

 

All Navy and Marine aviators get about 100 hrs fixed wing time in the T-34C (soon to be the Texan II) before moving on to helos. I would think this would be adequate intro to flying in the airplane mode. I don't see the need for multi-engine training, since the engines/prop-rotors on the Osprey are connected via a drive shaft. The emphasis on the multi-engine rating is handling the assymetric thrust and Vmc situations, not necessaily the loss of total thrust. After all, there is no multi-engine helo rating because you are really just dealing with a loss of power, where as a multi-engine airplane experiences yawing and rolling moments as a result of an engine failure.

[JDHelicopterPilot]

All Navy and Marine aviators get about 100 hrs fixed wing time in the T-34C (soon to be the Texan II) before moving on to helos. I would think this would be adequate intro to flying in the airplane mode. I don't see the need for multi-engine training, since the engines/prop-rotors on the Osprey are connected via a drive shaft. The emphasis on the multi-engine rating is handling the assymetric thrust and Vmc situations, not necessaily the loss of total thrust. After all, there is no multi-engine helo rating because you are really just dealing with a loss of power, where as a multi-engine airplane experiences yawing and rolling moments as a result of an engine failure.

 

 

Interesting. So you are saying that both engines drive a single "drive shaft" to the props like a twin helicopter? I didn't know it was built that way. I guess if it wasn't and each prop was driven seperate it would have a really bad case of assymetric thrust since the engines are so far out of the center line. I think we will see the BA609 in the corprate world in the future. It would be interesting to see what kind of training the FAA would require.

 

JD

[Rob Lyman]

Interesting. So you are saying that both engines drive a single "drive shaft" to the props like a twin helicopter? I didn't know it was built that way. I guess if it wasn't and each prop was driven seperate it would have a really bad case of assymetric thrust since the engines are so far out of the center line. I think we will see the BA609 in the corprate world in the future. It would be interesting to see what kind of training the FAA would require.

 

JD

 

Without the interconecting drive shaft a single engine failure would be a disaster in helicopter mode if not recognized immediately. Maybe some of the Chinook pilots can chime in here regarding interconnecting driveshaft failure. I do not know if they have an EP for this or they just bend over and kiss their butt goodbye.

 

For the V-22, read this article. About half way down this article you will find this paragraph:

 

An interconnecting driveshaft allows the Osprey to continue flying in the advent of an engine failure. Either engine can power both proprotors, although with reduced performance. The drive train subsystem is comprised of two proprotor gearboxes (PRGB), two tilt-axis gearboxes (TAGB), one mid wing gearbox (MWGB), an interconnect drive train, and an emergency lubrication system (ELS). The primary purpose of the drive system is to distribute engine power to the two proprotors, which generate lift and thrust. The drive system enables power distribution to the proprotors during all engines operating (AEO) and one engine inoperative (OEI) conditions.

[SGT_15U20]

Here in Iraq we have the first deployed V-22 unit flying in our vicinity all the time. I am a CH-47 crewmember so we see them where ever we go.

 

The take off is at about a 45 degree tilt forward

- this takes them them to about the departure corridor ( end of the runway )

 

At about this point they are probably somewhere around 1500 to 2000 ft AGL.

 

They tilt full forward like a plane and go.

 

Landing is the exact opposite, but when they come to a hover is the only time i see them looking like full helicopter mode, or when air taxiing to refuel.

[SGT_15U20]

Also, in regards to interconnecting driveshaft failure:

 

There is no such thing as a driveshaft failure. It breaks. When it breaks, the two rotor systems, for us CH47 guys, FWD and AFT, become un-phased. Being in "phase" is what allows two opposite rotor systems to pass within inches and feet of each other and never touch. With the "failure" of a driveshaft, this is now not the case and at a minimum the blade become unphased and make contact with each other. Also you could get things like a sudden jolt in your drivetrain.

 

US Army Aeromeds tell us that the force of just ONE blade coming off in flight, is around 100G's. Look up how many a human can handle, and you will quickly see that you will die before you even realize what has happend.

 

On another note, the way WE check for driveshaft issues, is by feeling down the length of the airframe from within the cabin, right under where our 9 driveshafts run. We are feeling for a "numbing" vibration from the driveshaft areas. A numbing feeling would mean we have a high freq vibe. This would tell us okay shut down somewhere, etc etc.

 

In addition, every 50 flight hours, we have a machine that has "vibe leads", we hook the leads up all over the aircraft, and it measure the vibrations. Abnormal vibrations are corrected numerous different ways.

 

I hoep that helps you see what dangers the interconnected driveshafts come with.

 

BUT, It does enable you to use a single engine, granted you arent above 62% dual engine torque. Helicopters autorotate, V-22s do not. They have glide slope just like an airplane.

 

BTW Ospreys do not EVER land full rotor tilted forward, "plane mode". The props would strike the ground. And what does US Army Aeromed say about blade strike in flight speed????? I answered it already, scroll up.

 

Take it easy guys. I am full of 47 info. Hit me up with anything you want to know.