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Bell-Boeing's MV-22 Osprey heads to Iraq
The MV-22 will have serve a seven month tour of duty in Iraq

Bell-Boeing's V-22 Osprey first took to the air nearly 20 years ago and the road to active duty has been a long one. When DailyTech last visited the tilt-rotor aircraft, the Air Force's CV-22 Osprey was criticized for its "poor aircraft availability" and "marginal operational availability" during desert testing at Kirkland Air Force Base.

"Frequent part and system failures, limited supply support, and high false alarm rates in the built-in diagnostic systems caused frequent flight delays and an excessive maintenance workload," claimed the report which was released earlier this year.

"This produces a maintenance and support burden that the Marines really can’t afford. All of the reliability problems that they continue to have here in the [United] States -- it’s going to drive them crazy overseas," said Philip Coyle, senior advisor for the Center for Defense Information.

Despite the troubles, the U.S. Marines will be deploying seven of its similar MV-22 Ospreys to Iraq in September. The Marines are hoping that the Osprey’s speed will allow it to quickly transport troops and make it less of a target for insurgents than slower, traditional helicopters.

"It is our fervent feeling that this aircraft is the most capable, survivable aircraft that we carry our most important weapons system in, which is the Marine or rifleman," said Lt. Gen. John Castellaw, the deputy commandant for aviation for the Marines. "If you've ever gone rabbit hunting, you know that it's harder to shoot a rabbit that's running than the one that's sitting still."

The push for the Osprey to enter regular military service has been a long time coming. In 2007 alone, there have been six crashes involving U.S. helicopters in Iraq. The Osprey's enviable speed (top speed 316MPH), ability to take-off and land like a helicopter and an operating range that is three to five times that of traditional helicopters should make it a great workhorse during its seven month deployment.

The V-22 Osprey is destined to replace the Marines' CH-46 Sky King by 2018. When compared to the CH-46, the Osprey has a range that is three times farther and has six to seven times the survivability in the field.

The tilt-rotor aircraft has been in development for over 20 years at a cost of over $20 billion USD.



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RE: biggest waste of taxpayer's money EVER
By masher2 (blog) on 4/17/2007 1:29:58 PM , Rating: 2
> "How often do helicopters and therefore will the Osprey be required to operate under 1,600 feet?"

You missed most of that equation. The Osprey isn't vulnerable when below 1,600 feet. It's vulnerable below that altitude only when configured for vertical flight, lacks sufficient forward airspeed, and loses both engines.

During 99% of the Osprey's mission time, it'll be configured for forward flight and thus, regardless of its altitude, will be able to perform a glide landing should it lose two engines.


RE: biggest waste of taxpayer's money EVER
By Jafo79 on 4/17/2007 3:09:43 PM , Rating: 2
I think you are confusing helicopter mode (not necessarily vertical) with vertical flight. Absolute vertical flight is avoided whenever possible due to the dangerous settling with power or vortex ring state that can occur should rate of descent exceed roughly 300fpm with almost zero airspeed. Unless absolutely necessary for the mission even helicopters follow a landing profile generally not reducing airspeed below 30knots or so until the rate of descent is less than 300 fpm. The v22 will be in helicopter mode on all descents to landing, that's a lot of the time. Furthermore the osprey can't come screaming into a stop like a helicopter, it must be much slower and gradual due to the aircraft's high likelihood of settling with power. The Osprey is even MORE susceptible to this problem and behaves much differently than a helicopter as 1 prop can enter into VRS while the other does not, this results in unequal lift and major control issues and eventually a crash just like in my last link because the damn reset button wasn't working for the computer! Let's not forget a computer is flying this thing, it's just receiving recommendations from a couple of humans! Therefore a single engine failure or single prop damaged by enemy fire let's say would almost certainly result in death for all aboard where as helicopters have demonstrated very survivable standards after taking fire. I guess only time will tell.


By masher2 (blog) on 4/17/2007 4:19:09 PM , Rating: 2
> "Absolute vertical flight is avoided whenever possible "

Of course. By configured for vertical flight, I mean nacelles pointed up, or "helo mode" if you prefer.

> "The v22 will be in helicopter mode on all descents to landing, that's a lot of the time"

A couple minutes out of a trip which might be several hundred miles? Sorry, thats not a significant fraction.

> "The Osprey is even MORE susceptible to [VRS]"

I'm sorry, but the more I research this the more I'm convinced its total hysteria. The Osprey is less endangered by VRS than a normal helo...it can easily get out of a VRS state, simply by a nacelle bleep, whereas a helo cannot.

So far one Osprey has crashed due to VRS, and that was due to pilot error. Here's a little writeup about that, by an ex-Army helo pilot, and owner of the site helicopterpage.com:
quote:
...Now, I know what you are thinking: The military ALWAYS blames the pilots.

In this [crash], it was pilot error...The V-22 that crashed was in a two-ship formation when the lead ship started a rapid deceleration. The trailing ship (The one that crashed) followed the lead ship beyond the point where it was safe and entered a descent that was in excess of 3000 feet per minute... there is no reasonable person who would assume that a pilot induced descent in excess of 10 times the minimum required rate of descent to enter Vortex Ring State would be the fault of the aircraft . While I offer my condolences to the families of those who were killed, I must state that the excessive rate of descent was the problem here, not the aircraft design. Had the pilot broken formation and departed the landing zone to set up for a new approach, he probably would be alive today. Does that mean I am saying that the aircraft is perfect? No. It does have some problems that need to be worked out, but this specific situation is not a case where the aircraft design is at fault...


"We don't know how to make a $500 computer that's not a piece of junk." -- Apple CEO Steve Jobs

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