"V-22 engine trouble may lead to supplier switch"
Mike
V-22 engine trouble may lead to supplier switch
By DAVE MONTGOMERY
Star-Telegram Washington Bureau
WASHINGTON -- The Rolls-Royce engines that power the Bell-Boeing MV-22
Osprey are wearing out faster than expected, raising the possibility
that the Marine Corps may have to look for another supplier, the head
of the Marines' V-22 program said Tuesday.
Marine Col. M. D. Mulhern told reporters that, although the dual
engines in the tilt-rotor aircraft perform well, they are not lasting
as long as the Marine Corps expected under a 1998 agreement with Rolls-
Royce.
"Now, as we are operating the airplanes, the engines aren't lasting as
long as we would like or as long as they would like," Mulhern said at
a briefing during an exposition sponsored by the Navy League.
Muller said the Marine Corps is working with the manufacturer but also
plans "to cast a wide net to see what's available," acknowledging that
rebidding the engine is a possible option. "We have some long-term
issues with Rolls-Royce that we need to work out," he said.
Rolls-Royce spokeswoman Maria Weber said in an e-mail response that
the engines have "met or exceeded all performance specifications" as
defined by the Marine Corps.
The Osprey, co-produced by Fort Worth-based Bell Helicopter, is
powered by two turboshaft engines capable of exceeding 6,500
horsepower. At least 100 tilt-rotor aircraft have been delivered to
the military, including 12 Ospreys performing combat missions in Iraq.
Mulhern said that the engine life span issue extends to all Ospreys,
not just those operating in the harsh desert combat conditions. The
average engine life span for the entire MV-22 fleet is 420 hours, only
slightly higher than the 380-hour average for the Ospreys in Iraq.
The Marine Corps will review its options over the remaining two years
of its agreement with Rolls-Royce to map out a "long-term strategy"
for powering the aircraft, Mulhern said. "That long-term strategy can
be everything from the status quo -- what we have today -- all the way
up to, we need to go find a new motor."
Mulhern told reporters that the aircraft will get heavier after the
Marine Corps installs an interim second gun and makes other
modifications. "As we get heavier, that may take more power," he said.
Weber said that Rolls-Royce has "a detailed growth strategy" for the
engine and plans to boost its horsepower to 7,000. The company is also
evaluating protective coatings designed to minimize sand and dust
erosion in the engine compressor, Weber said.
With Ospreys now deployed in combat, the performance of the tilt-rotor
aircraft is being closely watched after years of controversy that
included delays, steadily rising costs and two fatal crashes that
nearly led to the program's cancellation.
Marine Lt. Col. Rick Fuerst said the Ospreys based at al-Asad Air Base
in western Iraq have performed an array of transport missions,
including ferrying troops into combat, but have not encountered "any
direct fire." The combat Ospreys, attached to a Marine Corps squadron
known as the Thunder Chickens, are able to quickly reach higher
altitudes that enable them to get of the range of small arms fire,
Fuerst said.
The Osprey has provided years of employment at Bell's Tarrant County
plants; about 1,700 employees manufacture Osprey opponents in Grand
Prairie and Hurst. The aircraft is assembled by up to 800 workers at
another Bell plant in Amarillo.
Rolls-Royce produces the AE 1107C Liberty engines at its Indianapolis
plant.
Bell and co-producer Boeing plan to build a total of 458 tilt-rotors
for the Marines, Air Force and Navy.
ARES
A Defense Technology Blog
March 18, 2008
Oh, By The Way, We Need A New Engine for the V-22
by Bill Sweetman
The V-22 has made another bid for a Cleopatra award - presented by
Ares to programs that are terminally snake-bitten - by the revelation,
almost casually tossed out in mid-press conference at the Navy League
show by program manager Col. Matt Mulhern, that the AE 1107C engines
are not lasting long enough in service and that the Navy "could go as
far as re-engining the airframe".
Swapping engines is not trivial. It involves redesigning the engine
nacelle and all its associated systems and repeating much of the
flight test program. Mulhern wasn't giving any cost estimates, but
we're talking several hundred million dollars at the minimum. The fact
that the Navy is even talking about such a move says that the existing
engine is not performing acceptably and that nobody's quite sure how
much it will cost to fix.
The problem has to do with lifetime. All engines lose performance with
age, as heat, stress and contaminants take their toll on blades and
seals. The result is that the engine gets less efficient and has to
run hotter to produce rated power, and eventually temperatures reach a
limit. Mulhern won't say how long the current engine is lasting, but
it's somewhere between a few hundred hours - which the Navy feared was
going to be the engine's lifetime in Iraq - and several thousand,
which Rolls-Royce predicted and used as the basis for its power-by-the-
hour contract.
Mulhern says that he's not sure that the government ever believed
Rolls-Royce's estimates, which does raise the question of why program
officials signed that contract in the first place. However, it's not
hard to realize what would have happened if the need for a new engine
had been disclosed a few years ago, when the V-22 program was reeling
from a series of accidents and the need for an extensive redesign.
Fortunately, there is an alternative engine available - the General
Electric GE38-1B, under development for the CH-53K. Which is ironic,
because - as the few of us who were in this business when the V-22 got
started will recall - the GE38's design roots are in a project called
the Modern Technology Demonstrator Engine, which was originally
intended to be the definitive V-22 engine. But the AE 1107C was sold,
back then, as a lower-risk alternative.
Meanwhile, the Marines are saying very little about operational
experience in Iraq - and won't until the first operational squadron
crews return in about a month. Which, coincidentally, will be after
the Pentagon signs a multi-year contract for 167 more aircraft.
DefenseTech
New Engines for the V-22?
From our friends at Aviation Week (also covering the Sea-Air-Space
conference):
The lack of a viable long-term sustainment solution for the V-22's
Rolls-Royce engines may drive the U.S. Marine Corps to look for
entirely new engines in a few years.
"We need to move on, with or without Rolls-Royce," Marine Corps
Col.
Matt Mulhern, V-22 program manager, told reporters at the Naval Sea-
Air-Space Expo Tuesday.
Over the next two years, the Marine Corps will work on developing
a new strategy to solve issues that have arisen with V-22 engine
maintenance in Iraq. "We're casting a wide net to see what's
available. [The solution] could be status quo all the way up to
needing to find a new motor," Mulhern said.
When Rolls-Royce proposed a maintenance strategy back in 1998, it
was a "power-by-the-hour" solution, Mulhern said, which has turned out
to be insufficient.
"That business case analysis predicted the engine components would
last so many thousands of hours," he said. "I'm not sure the
government ever agreed with Rolls-Royce, but we thought it was a good
business case. Now, as we actually operate the aircraft, the engines
aren't lasting as long as we [or the government] would like."
Rolls-Royce cannot support the current strategy, Mulhern said. They
are unable to recoup the cost of engine maintenance under the power-by-
the-hour plan. "We'll have to move to more traditional engine
support," he said.
The engines are not lasting long in service because of erosion in the
compressor blades, which reduces engine efficiency and forces the
engine to run at higher temperatures to reach the same power. Another
concern is that the existing engine does not have enough margin to
handle expected weight growth.
The only turbine engine available in the same power class as the AE
3007 is the General Electric GE38-1B, selected last year as the
powerplant for the Sikorsky CH-53K helicopter. Mulhern says that the
Navy has not reached the point of estimating the cost of a re-engining
program.
Vince
> http://www.star-telegram.com/business/v-print/story/536059.html
>
> V-22 engine trouble may lead to supplier switch
> Mulhern said that the engine life span issue extends to all Ospreys,
> not just those operating in the harsh desert combat conditions. The
> average engine life span for the entire MV-22 fleet is 420 hours, only
> slightly higher than the 380-hour average for the Ospreys in Iraq.
>
no wonder they are only flying these gold plated turkeys a few hours a day
Vince
Mark Bradford
"Vince" <fir...@firelaw.us> wrote in message
news:X4edneEE4ue-Pnfa...@comcast.com...
Very comforting when I see one flying over my neighborhood every day.
Mark
Vince
there are about 80 of these turkeys
Im sure they can fly one or two a day for an hour or so
Vince
rjn
> The average engine life span for the entire MV-22 fleet is 420 hours,
> only slightly higher than the 380-hour average for the Ospreys in Iraq.
This is what, about 10% of the TBO most turbine operators expect?
Or is this, ugh, useful life, and not just time to major overhaul?
--
Regards, Bob Niland mailto:na...@ispname.tld
http://www.access-one.com/rjn email4rjn AT yahoo DOT com
NOT speaking for any employer, client or Internet Service Provider.
Peter Skelton
<emai...@yahoo.com> wrote:
>Mike <yard22...@yahoo.com> quoted:
>
>> The average engine life span for the entire MV-22 fleet is 420 hours,
>> only slightly higher than the 380-hour average for the Ospreys in Iraq.
>
>This is what, about 10% of the TBO most turbine operators expect?
>
>Or is this, ugh, useful life, and not just time to major overhaul?
If a new version of the PT-6 twin-pack had a 400 hour life
between overhaul in 1980, there'd have been a design team looking
for employment.
One thing that shocks me is the small difference in life between
engines used in harsh environment and those in mild. There are a
number of strategies available to lengthen engine life, some of
those use some kind of filtering and restrict airflow to the
engine, which can be troublesome.
It's possible that there's a gearbox problem. An article of ths
sort would not differentiate between gearbox and engine, this si
a much more complex than normal gearbox because of the
cross-shafting.
Then there's software, especially for fuel-control.
It's fun to speculate, but . . .
Peter Skelton
Jack Linthicum
> On Wed, 26 Mar 2008 16:49:19 -0700 (PDT), rjn
>
sand, a natural abrasive
Vince
Various sources make clear that it is a compressor problem
The AE 1107C shares a common core with other Rolls Royce engines but its
only use is on the V-22
The V-22 design demanded a high performance (power to weight ratio) and
high reliability, so it is not fundamentally surprising that durability
suffered
Vince
Peter Skelton
Undoubtedly explaind the small difference between the desert and
other engine lives.
Did you read any of the thread?
Peter Skelton
Jack Linthicum
Yes, the usual V-22 back and forth.
Peter Skelton
I'll take that as a clear no.
Peter Skelton
Jack Linthicum
Please tell me the profound differences between this thread and many
V-22 Osprey back and forths.
Peter Skelton
It contains real data peole are responding to, which you ignored
"The average engine life span for the entire MV-22 fleet is 420
hours, only slightly higher than the 380-hour average for the
Ospreys in Iraq."
Peter Skelton
Jack Linthicum
> On Thu, 27 Mar 2008 14:14:07 -0700 (PDT), Jack Linthicum
>
>
>
Yes, information followed by endless back and forth with relation to
the original problem, which turns out to be an outgrowth of the
selection system. Really heavy stuff.
Jack Linthicum
More on that engine selection. It isn't a new problem with that
particular engine in helicopters. Notice "poorly filtered"
http://blog.wired.com/defense/2008/03/v-22-may-need-n.html
V-22 May Need New Engine (Updated)
By Sharon Weinberger March 19, 2008 | 2:28:58
The revolutionary V-22 tiltrotor, which was recently sent to Iraq, has
a little problem. Or actually, it has a big problem: its engines are
wearing out, and fast. Yes, engines wear out, but this isn't quite
like wearing down the tires on a car.
<snip duplicated material>
UPDATE: "This shouldn't come as a surprise," writes one Kiowa Warrior
helicopter pilot.
The Rolls Royce 250-C30R/3 on the OH-58D had wear problems too.
When my unit deployed 16 aircraft to NTC [the National Training Center
at Ft. Irwin] from Colorado Springs in June 2002 (a regularly
scheduled rotation, but with a heavy emphasis on preparing for Iraq)
we replaced several engines - I want to say six. This was mainly due
to wear on the compressor from the poorly filtered airflow. Until
around 2002, the 58D did not have what you would think of as an air
filter - it used a "particle separator" that kept big chunks out, but
let a lot of smaller particles in.
The compressor blades were being damaged, and it was impacting the
engine performance. At the time we were experimenting with filters -
including panty hose. Prior to deployment to Iraq, we fielded a much
more robust filter system, using petroleum coated filter elements
similar to a cars air filter. The new filters improved performance,
and greatly reduced the wear and tear on the engine compressors. I
can't speak to the exact nature of the Osprey's problems, but I think
the issue is likely due to a less robust filtering system, and
extended operations in the sandy/dusty environments in Iraq. I would
think that the Osprey's engine air filtering system was designed for
the "occasional" sand/dust landing, but meant to live on tarmac. Now
they're living like the Army and Marines live...in the dirt.
Contrary to some perception... we frequently operated in sandy and
dusty LZs [landing zones] at our training areas, and it got even worse
at the deserts of NTC. Long term wear caught up with us, and the
result was a lot of engine replacements. Our OPTEMPO [operational
tempo] in Iraq was pretty high - I think we flew roughly a (garrison)
years worth of flight hours in a couple of months in Iraq, so it's
possible that it's a "normal" amount of wear and tear is catching up
with with V-22 engines.
Typhoon502
wrote:
> More on that engine selection. It isn't a new problem with that
> particular engine in helicopters. Notice "poorly filtered"
>
> http://blog.wired.com/defense/2008/03/v-22-may-need-n.html
>
> V-22 May Need New Engine (Updated)
> By Sharon Weinberger March 19, 2008 | 2:28:58
>
> The revolutionary V-22 tiltrotor, which was recently sent to Iraq, has
> a little problem. Or actually, it has a big problem: its engines are
> wearing out, and fast. Yes, engines wear out, but this isn't quite
> like wearing down the tires on a car.
>
> <snip duplicated material>
>
> UPDATE: "This shouldn't come as a surprise," writes one Kiowa Warrior
> helicopter pilot.
>
> The Rolls Royce 250-C30R/3 on the OH-58D had wear problems too.
> When my unit deployed 16 aircraft to NTC [the National Training Center
> at Ft. Irwin] from Colorado Springs in June 2002 (a regularly
> scheduled rotation, but with a heavy emphasis on preparing for Iraq)
> we replaced several engines - I want to say six. This was mainly due
> to wear on the compressor from the poorly filtered airflow.
Huh. Seems like Rolls Royce has got some 'splaining to do.
Peter Skelton
Still haven't read it Jack?
Let me explain: this sub-thread is consideration of why V-22
compressors are failing early with a small difference between
Iraq service and other services.
You chimed in with a comment about sand.
I was polite - F*g idiot is more what you deserve.
Peter Skelton
Jack Linthicum
> On Fri, 28 Mar 2008 08:08:36 -0700 (PDT), Jack Linthicum
>
>
>
Read something besides your own repititions
UPDATE: "This shouldn't come as a surprise," writes one Kiowa Warrior
helicopter pilot.
The Rolls Royce 250-C30R/3 on the OH-58D had wear problems too.
When my unit deployed 16 aircraft to NTC [the National Training Center
at Ft. Irwin] from Colorado Springs in June 2002 (a regularly
scheduled rotation, but with a heavy emphasis on preparing for Iraq)
we replaced several engines - I want to say six. This was mainly due
Peter Skelton
or your snippy nonsense
>UPDATE: "This shouldn't come as a surprise," writes one Kiowa Warrior
>helicopter pilot.
>
> The Rolls Royce 250-C30R/3 on the OH-58D had wear problems too.
>When my unit deployed 16 aircraft to NTC [the National Training Center. . .
So are you trying to say sand was some kind of huge surprise or
that design incompetence is the problem. If the former, you're a
fool; if the latter, a liar.
Have a nice day.
Peter Skelton
Jack Linthicum
And you are a terrible listener
Andrew Swallow
Try. The USA uses (wrote) NATO standards. NATO standards are designed
for Northern Europe. Plenty of rain and snow in Europe but very little
hot, dry desert. So sand and dust filters were neither specified nor
fitted. British Army rifles used to have problems working in a dusty
environment.
I have read WWII newspaper articles about tanks being fitted with sand
filters. I wonder what other equipment, specifications and standards
need modifying?
Andrew Swallow
Vince
except that the compressors in US engines are failing too
Vince
Andrew Swallow
[snip]
>
> Let me explain: this sub-thread is consideration of why V-22
> compressors are failing early with a small difference between
> Iraq service and other services.
Lets take this talk off sand.
Why were V-22 engines specified as having a different working life to
Jeep engines?
Jeep and trunk engines are not so heavy that the additional cost
of buying 5 - 10 extra engines for the V-22 can be easily cost
justified.
Andrew Swallow
Vince
I'm having trouble under standing your question
I think the whole point is that they didn't meet the lifetime
expectations. what they met were the contract "specifications"
Because this was a Power by the hour contract (think of it a s a service
contract) the cost issue hits hard when the initial contract is up
http://www.globalsecurity.org/military/systems/aircraft/v-22-propulsion.htm
Since the engines fail at 400 hours
as with every other screwup on this turkey, they gave prizes to the
idiots who thought it up
V-22 OSPREY CITED FOR EXCELLENCE IN ACQUISITION REFORM
By Gidge Dady, V-22 Public Affairs
NAVAL AIR STATION PATUXENT RIVER, MD. (May 4) -- Dr. H. Lee Buchanan,
assistant secretary of the Navy for Research, Development and
Acquisition, presented the V-22 government and industry team the 1999
Department of Defense (DOD) Acquisition Executives (DAE) Certificate of
Achievement for excellence in Acquisition Reform here May 3.
The V-22 Osprey tilt-rotor aircraft is the slated replacement for the
Marine Corps' aging fleet of Ch-46 Sea Knight and CH53D Sea Stallion
helicopters.
Colonel Nolan Schmidt, V-22 program manager, accepted the prestigious
award on behalf of the V-22 team, which is cited for its work in
establishing a "highly-innovative, commercial, fixed-price contract for
commercial engine procurement and commercial logistic support of the
Allison AE-1107C engine." This contract is known as "Power by the Hour"
because Allison provides the majority of the maintenance and supply
support beyond the flight line. This support includes configuration
management, training, spare parts inventory, and engine certification.
http://www.fas.org/man/dod-101/sys/ac/docs/990504-v22.htm
what this fluff does not say is who carries the can when the contract
runs out
Col Matt Mulhern, V-22 Program Manager said that the service was
preparing to scour engine manufacturers - ‘casting as wide a net as
possible’ - for possible solutions to providing power in the future.
The V-22 situation is one that applies across the board, ‘not only
connected with the Iraqi deployment,’ Mulhern said. Intention now is to
fashion a two- year ‘bridging contract’ with Roll Royce while the
implications are studied.
‘But right now I don’t believe the power by the hour case can be
supported much longer,’ he said.
OOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOps
Vince
Andrew Swallow
> Andrew Swallow wrote:
>> Peter Skelton wrote:
>> [snip]
>>
>>>
>>> Let me explain: this sub-thread is consideration of why V-22
>>> compressors are failing early with a small difference between
>>> Iraq service and other services.
>>
>> Lets take this talk off sand.
>>
>> Why were V-22 engines specified as having a different working life to
>> Jeep engines?
>>
>> Jeep and trunk engines are not so heavy that the additional cost
>> of buying 5 - 10 extra engines for the V-22 can be easily cost
>> justified.
>>
>> Andrew Swallow
>
> I'm having trouble under standing your question
>
> I think the whole point is that they didn't meet the lifetime
> expectations. what they met were the contract "specifications"
> Because this was a Power by the hour contract (think of it a s a service
> contract) the cost issue hits hard when the initial contract is up
>
> http://www.globalsecurity.org/military/systems/aircraft/v-22-propulsion.htm
>
> Since the engines fail at 400 hours
420 hours used 8 hours a day produces a life time of 420/8 = 52.5 days.
That is the equivalent of a jeep having to scrap its engine every 2
months. The army would consider a jeep that weak a joke.
I accept the point that aircraft and land vehicles are different. So
I will compare the V-22's engine with other aircraft engines produced by
Rolls-Royce.
<http://www.rolls-royce.com/civil_aerospace/products/airlines/rb211524/default.jsp>
The RB211-524's website boasts
"# First engine ever to achieve more than 27,500 hours on-wing"
27,500 / 420 = 65.5 times as long.
So the specification for the replacement engine needs to specify a life
of something like 10,000 hours.
Andrew Swallow
Peter Skelton
Was your four word comment a lie or stupidity?
You didn't read the thread before you jumped in, you've been
dodging ever since. I've noticed that the real iron-headed can't
admit a mistake types do that and then accuse others of whatever
sin they've committed themselves.
Peter Skelton
Jack Linthicum
> On Fri, 28 Mar 2008 16:04:38 -0700 (PDT), Jack Linthicum
>
>
>
I noticed that too, like the guy who ignores a statement by someone
who has experienced similar problems with another helicopter that use
the Rolls-Royce 250-C30R/3 engine. Lack of real air filtration, I
believe it was.
I count six words, an example, I would believe, of your ability to
read for content.
Peter Skelton
That isn't quite correct. When aircraft people talk about engine
life, they mean the time it can stay in the aircraft, or time
between overhauls.
>I accept the point that aircraft and land vehicles are different. So
>I will compare the V-22's engine with other aircraft engines produced by
>Rolls-Royce.
>
><http://www.rolls-royce.com/civil_aerospace/products/airlines/rb211524/default.jsp>
>The RB211-524's website boasts
>"# First engine ever to achieve more than 27,500 hours on-wing"
>
>27,500 / 420 = 65.5 times as long.
>
A lie. BTW PT-6's achieved evergreen certification for Rocky
Mountian Air about the time the RB211 went into service. RR meant
"large jet engine".
>So the specification for the replacement engine needs to specify a life
>of something like 10,000 hours.
>
There's a bit of difference between an airline engine and a
helicopter engine. The helo version of the engine I mentioned
above had widely varrying service lives, usually in the low
thousands of hours (I had little to do with it MMV).
If the aircraft has to be taken out of service periodically for
other maintenance, it's not often worth the effort to extend
engine life past that.
Peter Skelton
Vince
>>> I think the whole point is that they didn't meet the lifetime
>>> expectations. what they met were the contract "specifications"
>>> Because this was a Power by the hour contract (think of it a s a
>>> service contract) the cost issue hits hard when the initial
>>> contract is up
>>>
>>> http://www.globalsecurity.org/military/systems/aircraft/v-22-propulsion.htm
>>
> That isn't quite correct. When aircraft people talk about engine
> life, they mean the time it can stay in the aircraft, or time between
> overhauls.
TOW is time on wing
MTBO Mean time between overhauls
Is replacing the compressor part of an "overhaul" ?
snipped
> There's a bit of difference between an airline engine and a
> helicopter engine. The helo version of the engine I mentioned above
> had widely varrying service lives, usually in the low thousands of
> hours (I had little to do with it MMV).
> If the aircraft has to be taken out of service periodically for other
> maintenance, it's not often worth the effort to extend engine life
> past that.
I suspect there are two different issues
1) stateside maintenance is performed directly by rolls royce
by Staff Writers
Washington DC (SPX) Jan 25, 2006
Rolls-Royce has been awarded two contracts from the U.S. Naval Air
Systems Command for the purchase and continued support of AE 1107C
Liberty engines powering V-22 Osprey tiltrotor aircraft.
Under the purchase contract, Rolls-Royce will produce 28 engines for
the MV-22 and CV-22 versions of the aircraft in 2006-07. The engines are
manufactured in Indianapolis, IN.
The services contract includes a new option year for a Power By The
Hour# contract for maintenance support this year for the gas-turbine
engines. Most of the work will be performed at Marine Corps Air Station
New River in North Carolina, with additional work at Indianapolis and
Amarillo, Texas.
2) the ospreys in irac fly only a few hours a day
in the first three months they averaged less than 2 hours a day
since they are not being deployed in the summer , they can be babied
along at 2 hours a day for the 7 moth deployment
3) rolls royce has minimal manpower in iraq
Bell-Boeing is sending 14 civilian technicians to Iraq with VMM-263 to
help maintain its Ospreys and Rolls-Royce is sending two
representatives. The contractors also have made a special effort to
ensure that adequate
supplies of spare parts reach the squadron at Al Asad, and the Marines
gave VMM-263 first call on parts and personnel within the Corps’ V-22
fleet prior to their mid-September departure.
What is not clear is whether something as major as a compressor
replacement can be done in Iraq (replacing the engine is different)
4) The real question is "when did the USMC become aware of the short
engine life?"
Service contracts like "power by the hour" are a way to keep upfront
costs low but only work if they run the life of the machine. its
essentially leasing versus buying
I suspect that the USMC signed 1 year to 2 year contracts (see above on
new option year) and is now being hit with massive price increases
because the engine wear out
the contracts put the cost on rolls royce for long enough to get the
v-22 deployed. now the bill is coming due and the USMC doesnt have the
money
Vince
Peter Skelton
I ignored it how? You posted it later. It is not relevant to the
question at hand.
>I count six words, an example, I would believe, of your ability to
>read for content.
"sand, a natural abrasive"
Can't count either eh?
Peter Skelton
Peter Skelton
wrote:
>Peter Skelton wrote:
>
>>>> I think the whole point is that they didn't meet the lifetime
>>>> expectations. what they met were the contract "specifications"
>>>> Because this was a Power by the hour contract (think of it a s a
>>>> service contract) the cost issue hits hard when the initial
>>>> contract is up
>>>>
>>>> http://www.globalsecurity.org/military/systems/aircraft/v-22-propulsion.htm
>
>>>
>> That isn't quite correct. When aircraft people talk about engine
>> life, they mean the time it can stay in the aircraft, or time between
>> overhauls.
>
>TOW is time on wing
>
>MTBO Mean time between overhauls
>
TOW and TBO (MTOW & MTOW) are close enough that I would not care
to rely on news reports separating them. For many "small"
turbines they are the same.
>
>Is replacing the compressor part of an "overhaul" ?
>
That depends on the engine's condition. Certainly it can be
(there are engines whose compressors can be changed on-wing - it
would be an advantage to an AG (agricultural) engine, for
example).
I'm not aware of an engine who's compressor is changed as a
routine part of an overhaul. (There couldl be, I suppose.)
<s>
Peter Skelton
Jack Linthicum
"Contrary to some perception... we frequently operated in sandy and
dusty LZs [landing zones] at our training areas, and it got even worse
at the deserts of NTC. Long term wear caught up with us, and the
result was a lot of engine replacements."
From the reference.
It's called a reference point and it doesn't matter when it appears in
an argument if it proves or supports an earlier point.
"And you are a terrible listener"
still
Peter Skelton
And thats the evidence that proved you either a liar or a fool.
My comment after reading it showed that I read it. Your continued
accusations in the face of the evidence are further proof, as if
that were needed.
You are either a liar or a fool
still
Peter Skelton
Jack Linthicum
> On Sat, 29 Mar 2008 11:21:37 -0700 (PDT), Jack Linthicum
> >> >> >> >> >> >> >> >sand, a natural abrasive
-----------------------------------------------------------------------------------------------------------------------
> >> >> >> >UPDATE: "This shouldn't come as a surprise," writes one Kiowa Warrior
> >> >> >> >helicopter pilot.
>
> >> >> >> > The Rolls Royce 250-C30R/3 on the OH-58D had wear problems too.
> >> >> >> >When my unit deployed 16 aircraft to NTC [the National Training Center. . .
---------------------------------------------------------------------------------------------------------------------
You seem to qualify for the first.
--------------------------------------------------------------------------------------------------------------------
> >UPDATE: "This shouldn't come as a surprise," writes one Kiowa Warrior
> >helicopter pilot.
>
> > The Rolls Royce 250-C30R/3 on the OH-58D had wear problems too.
> >When my unit deployed 16 aircraft to NTC [the National Training Center. . .
>
> So are you trying to say sand was some kind of huge surprise or
> that design incompetence is the problem. If the former, you're a
> fool; if the latter, a liar.
----------------------------------------------------------------------------------------------------------------------
>
> Have a nice day.
>
> Peter Skelton
You seem to have removed all of the text and implied that the
particles that the filters didn't catch were insignificant. The full
text says you are wrong, but that is to be expected.
-------------------------------------------------------------------------------------------------------------------
UPDATE: "This shouldn't come as a surprise," writes one Kiowa Warrior
helicopter pilot.
The Rolls Royce 250-C30R/3 on the OH-58D had wear problems too.
When my unit deployed 16 aircraft to NTC [the National Training Center
at Ft. Irwin] from Colorado Springs in June 2002 (a regularly
scheduled rotation, but with a heavy emphasis on preparing for Iraq)
we replaced several engines - I want to say six. This was mainly due
to wear on the compressor from the poorly filtered airflow. Until
around 2002, the 58D did not have what you would think of as an air
filter - it used a "particle separator" that kept big chunks out, but
let a lot of smaller particles in.
The compressor blades were being damaged, and it was impacting the
engine performance. At the time we were experimenting with filters -
including panty hose. Prior to deployment to Iraq, we fielded a much
more robust filter system, using petroleum coated filter elements
similar to a cars air filter. The new filters improved performance,
and greatly reduced the wear and tear on the engine compressors. I
can't speak to the exact nature of the Osprey's problems, but I think
the issue is likely due to a less robust filtering system, and
extended operations in the sandy/dusty environments in Iraq. I would
think that the Osprey's engine air filtering system was designed for
the "occasional" sand/dust landing, but meant to live on tarmac. Now
they're living like the Army and Marines live...in the dirt.
Contrary to some perception... we frequently operated in sandy and
dusty LZs [landing zones] at our training areas, and it got even worse
at the deserts of NTC. Long term wear caught up with us, and the
result was a lot of engine replacements. Our OPTEMPO [operational
tempo] in Iraq was pretty high - I think we flew roughly a (garrison)
years worth of flight hours in a couple of months in Iraq, so it's
possible that it's a "normal" amount of wear and tear is catching up
with with V-22 engines.
-------------------------------------------------------------------------------------------------------------------
Kerryn Offord
<SNIP>
> 2) the ospreys in irac fly only a few hours a day
>
> in the first three months they averaged less than 2 hours a day
> since they are not being deployed in the summer , they can be babied
> along at 2 hours a day for the 7 moth deployment
So what is the operational radius when operating for less than 2 hours?
Vince
it's an average
They are overwhelmingly used as vip transports and expensive cargo haulers
Vince
Peter Skelton
<jackli...@earthlink.net> wrote:
<mercy snippage>
>
>You seem to have removed all of the text and implied that the
>particles that the filters didn't catch were insignificant. The full
>text says you are wrong, but that is to be expected.
>
Where in hell did I say that Jack?
Come on you lying bastard, out with it. You seem to have all the
text in the thread at your finger tips, should be easy for you to
substantiate, if only there were some truth to it.
Peter Skelton
Jack Linthicum
> On Sat, 29 Mar 2008 12:16:21 -0700 (PDT), Jack Linthicum
>
>
> <mercy snippage>
>
>
>
> >You seem to have removed all of the text and implied that the
> >particles that the filters didn't catch were insignificant. The full
> >text says you are wrong, but that is to be expected.
>
> Where in hell did I say that Jack?
>
> Come on you lying bastard, out with it. You seem to have all the
> text in the thread at your finger tips, should be easy for you to
> substantiate, if only there were some truth to it.
>
> Peter Skelton
You implied that the problem couldn't be the filtering being
inadequate, I suggested a different environment, which you found not
suitable, so I got a quote from someone who had actually used the
Rolls Royce 250 engine on an actual helicopter and had found the
problem was inadequate filtering of the air into the engine. The helo
person described many "field" attempts to solve the problem and you
scoffed at them. Where is the lie?
Peter Skelton
Your first eleven words are a flat lie.
The last few words of your third sentence are another flat lie.
Peter Skelton
Richard Casady
wrote:
>You seem to have all the
>text in the thread at your finger tips, should be easy for you to
>substantiate, if only there were some truth to it.
I use Agent and I keep everything forever. I have 340 000 SMN posts on
this hard drive, five or so years worth. They are all in one window,
five days, five years, Agent doesn't care. I can highly recommend that
particular news reader.
Casady
Jack Linthicum
So are you trying to say sand was some kind of huge surprise or
Richard Casady
<jackli...@earthlink.net> wrote:
>problem was inadequate filtering of the air into the engine. The helo
>person described many "field" attempts to solve the problem and you
There were problems with sand and no filters during Desert Storm. When
will they ever learn?
Casady
Jack Linthicum
wrote:
> On Sun, 30 Mar 2008 13:10:39 -0700 (PDT), Jack Linthicum
>
> >problem was inadequate filtering of the air into the engine. The helo
> >person described many "field" attempts to solve the problem and you
>
> There were problems with sand and no filters during Desert Storm. When
> will they ever learn?
>
> Casady
I have a sneaking suspicion that the filter manufacturer was in a
state or district that was against the V-22. Check out Maryland and
Vince for clues. On the other hand the panty hose manufacturers may
have missed a bet. Not the first time I have heard of that fix,
although on one of the examples I heard of the trick was getting the
pantyhose to put on the filter inlet.
Peter Skelton
Nice of you to post the evidence. Now that we've dealy with your
first lie, would you like to convict yourself on the second?
Peter Skelton
Peter Skelton
The air flow for a turbine is huge, pressure drop accross a
filter is a bad thing. It's a non-trivial problem. It might even
be that it's cheaper to accept the overhauls.
It's also not proven here that erosion is the problem, there are
other candidates.
Peter Skelton
Jack Linthicum
> On Sun, 30 Mar 2008 14:12:36 -0700 (PDT), Jack Linthicum
>
>
>
Well, we could start with your post saying "It's a non-trivial
problem. It might even
be that it's cheaper to accept the overhauls"
By the way what are the lies? Should see some evidence here rather
than noise.
Peter Skelton
How is that evidence of me scoffing at your reference. Nice try,
but too idiotic.
>By the way what are the lies? Should see some evidence here rather
>than noise.
I identified the lies directly above, it's still there.
Peter Skelton
Jack Linthicum
Try again, that's an old dodge.
Peter Skelton
Stupid liar:
Jack Linthicum
> On Mon, 31 Mar 2008 05:01:27 -0700 (PDT), Jack Linthicum
>
>
>
The Rolls Royce 250-C30R/3 on the OH-58D had wear problems too.
Your response
TMOliver
"Richard Casady" <richar...@earthlink.net> wrote in message
news:47ff02e4....@news.east.earthlink.net...
Long about 1940 or so (maybe 1941), strange new drag-inducing intakes below
the props of Spitfires and Hurricanes operating in North Africa show that
the RAF was taking sand seriously and attempting to keep it out of
carburetors.
V-22s employing either vertical takeoff or landings would appear to me to be
prime candidates for blowing dust/sand/grit/forage caps/etc., high enough in
the air to cause it to be ingested by the air intakes.
I seem to recall that there's an SOP for the time interval between C130 take
offs and landings from desert air strips, time to allow the shit to
settle....
TMO
Peter Skelton
So you are utterly unable to support your contentions and are
reposting the same material in hopes no one will notice.
Good luck with that one.
F*g liar, and brainless to boot.
>> >> >> >> Your first eleven words are a flat lie.
>>
>> >> >> >> The last few words of your third sentence are another flat lie.
>>
>> Peter Skelton
Peter Skelton