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-   -   V22 Osprey discussion thread Mk II (https://www.pprune.org/rotorheads/490255-v22-osprey-discussion-thread-mk-ii.html)

Ian Corrigible 30th Aug 2014 03:23

US military seeking replacement V-22 engines

The US military has put out a call for drop-in replacement engines to power all variants of its Bell-Boeing V-22 Osprey tiltrotor aircraft.

A request for information (RFI) released on 26 August seeks information from industry “on alternative power plant solutions capable of powering all MV/CV-22 (all models) Osprey as well as any foreign military sales aircraft in a safe, reliable, cost-effective and sustainable manner which demonstrate a best value to the government.”
The program has been looking at an engine switch since at least 2008 due to the AE1107's low operational TBOs; the CH-53K's GE38 is an obvious contender, having originally been offered for JVX (as the GE27) in the 1980s.

I/C

riff_raff 30th Aug 2014 22:45

I agree that the GE38 seems like the most obvious candidate for a "drop-in" replacement engine. As noted the basis engine was the GE27 which was intended for the V-22, so it has the correct basic size, shape, power turbine speed, etc. The biggest changes GE would need to make on the current GE38 engine would be repositioning the engine mounted accessories to match the AE1107C's and modifying the lube oil system for tilting. I understand the GE38's original design allowed for incorporating a lube system capable of tilting, so this mod may not be too difficult.

However, since the basic design of the GE38 is fairly similar to the AE1107C, I can't see what you would do with the GE38 to address the service life and reliability problems that could not be applied to the existing AE1107C.

Ian Corrigible 31st Aug 2014 04:15

The GE38's compressor (5-stage axial + 1-stage centrifugal) should offer improved characteristics compared to the incumbent AE1107's 14-stage axial compressor (a product of its T56 heritage). As discussed in the previous V-22 thread, axi-centrif compressors are less sensitive to erosion/corrosion, with our very own Paco estimating that the axi-centrif configuration "increases an engine's resistance to [compressor stalls] by about 10 times."

I/C

Ian Corrigible 29th Oct 2014 15:23

Various updates:
  • Bell believes Japan will order Ospreys in early 2015, becoming the second customer (or maybe the first, given the above...)
  • Aerospace Daily reports that Bell's V-22 testbed aircraft has been seen flying over Fort Worth equipped with a 2.75-in. rocket pod fitted on the port side of the forward fuselage, the munition in question believed to be APKWS
I/C

belly tank 12th Nov 2014 22:32

V22's Landing in Brisbane for the G20 summit:eek:

G20 Helicopter (Osprey) Fail


John Eacott 13th Nov 2014 01:22

Another view of the same fuster cluck. Not the best advert for international relations, very lucky there wasn't a multi vehicle bingle. The press would have been all over the V22 like alligator shoes in a Gold Coast trattoria.


rh200 13th Nov 2014 05:22

Being hailed as the first chopper fail of the G20:ugh:

http://resources2.news.com.au/images...998d90ddfa.jpg

FH1100 Pilot 13th Nov 2014 16:43

(Sigh). SMH. Will they ever learn?

Lucky we didn't have another Operation Eagle Claw all over again.

jeffg 13th Nov 2014 17:39

Nice try, FH, but you really know very little about military rotary wing aircraft and how they're flown. You certainly know nothing of the V-22 (that's obvious). Instead of listing your blog site maybe you should spend a little more time actually learning about these crazy contraptions. Just a thought, mm'kay?

FH1100 Pilot 14th Nov 2014 20:21

jeffg:

Nice try, FH, but you really know very little about military rotary wing aircraft and how they're flown. You certainly know nothing of the V-22 (that's obvious). Instead of listing your blog site maybe you should spend a little more time actually learning about these crazy contraptions. Just a thought, mm'kay?

AAAHAHAHAHAH! Hoo-man, using my own words against me! HAHAHAH- :::slaps knee:::HOHOHOHO. So funny! So clever! So original!

I mean, not.

Jeff, seriously, you've got to stop this neurotic following of me around and commenting on *every* post I make with your incessant contradicting and insulting posts of your own. It's weird, dude. It's making you look...I dunno...obsessed. Are you, like, stalking me or something? Do you have a thing for me? (You *are* an EMS pilot, right?) Because I gotta tell you (and I should probably do this in a private message), I'm just not into you, bud.

Now, to the matter at hand - the landing of the three Ospreys in Australia:

We all know by now that Ospreys make a huge downwash, right? We know this; it is not news. It was dramatically proved to us back in 2010 when the Marines landed their Osprey in that park in Staten Island, N.Y. Remember? Nobody stopped to think, "Heyyyyy, this thing puts out quite a bit of downwash! Maybe we shouldn't go into that...naaaaahh, fire it up- let's go!" Subsequently, it was like a scene from that movie, "Twister." Young children, pregnant mothers, and babies in strollers were strewn like so many Texas tumbleweeds; vehicles from Smart cars to city buses were scattered and flipped like toys, stripped of all paint, windows sandblasted opaque.

"Mommy...make it stop!!!"

You'd think the Marines would've learned from that. But no. Somebody got the great idea to put three Ospreys into a little dirt field in Brisbane. Hilarity ensued. We're just fortunate I guess...maybe it was the grace of God (yes atheists, grace of God) that there wasn't a fatal accident on that highway. But hey, what are a few dead Australians when it comes to the needs of the mighty U.S. military! Am I right?

But don't listen to me, I don't know nuthin' about military aircraft.

Lonewolf_50 14th Nov 2014 20:47

I wonder who did the LZ recon, and what they think of their work now. :uhoh:

As John pointed out, good thing something bad didn't happen on that road.

FH: the over-the-top act is wearing thin.

John Eacott 14th Nov 2014 21:01


Originally Posted by Lonewolf_50 (Post 8742844)
I wonder who did the LZ recon, and what they think of their work now.

Which has got me thinking: if the recon was done 2-4 weeks ago that paddock was probably green grass and would have seemed quite suitable. November is renowned in Australia for the country to turn brown as the wind shifts northerly and brings down the hot, dry air. Last week my place was green, three days ago I cut 5 acres of grass and it now looks as brown as the paddock in the photo.

But for the downwash to blow over the safety barriers indicates a certain lack of forethought by someone :hmm:

http://resources2.news.com.au/images...998d90ddfa.jpg

Boudreaux Bob 14th Nov 2014 22:47

Last time I checked it was quite normal for big Rotorcraft to blow a lot of dust and debris about the place. So what is new here?

If you have folks that are used to working in Desert Locations then I would think this Paddock seemed no big deal.

It does make one wonder why the Fire Brigade was not brought in to wet the place down a bit exactly as the USFS does in its operations.

I bet next time that bit of Prior Planning shall be on the Check List.

jeffg 15th Nov 2014 02:23

Given the limited information available the only known is that it appears someone made a bad decision. What's not known is who and one should not presume to know. Perhaps it was the Marines and they didn't account for the environmental effects of their decision. Or as suggested they did a proper site survey but didn't adequately understand the changing environment. It wouldn’t be the first time a site survey was done weeks to months in advanced, especially for a high profile event at such a distance from home. Perhaps the operational and security requirements overrode the environmental effects and the host country or higher hq choose the LZ and the Marines had no say in the LZ selection. So quite possibly they landed where they were told despite their misgivings. This also would not be a first. Unless one knows the who and the why perhaps one should refrain from drawing conclusions?

The Sultan 15th Nov 2014 04:36

Rumor has it that the site survey team were Australian helicopter experts who were also involved in the procurement of the NH-90, Tiger and Seasprite. Maybe they just wanted drivers to practice for the imminent fires.

The Sultan

tottigol 15th Nov 2014 18:43

Whoever it was that picked the LZ, should have considered the GOLF COURSE to the right of the tree line, it seems to have kept green grass and/or the water from the visible pond could have been used to wet the dried out LZ.

Any of you sales type ever fly EMS?

I am quite sure the LZ was reconned by ground well in advance and again immediately prior the arrival of the Ospreys. So this seems a classic case of bad communication, between civil servants and our valued USMC.
I can see the crew in the V-22 going "OH, f*#k" thirty times in a row before touch down and cringing before the expected multi-vehicle crash.

Sultan, does Bell make ANY helicopter that is even remotely comparable to the helicpters you mentioned?

While "Florida-Bob" often overstates his opinion, I know his experience (if dated) is way more valuable than some sales-rep-turned-military-reject posting here.

21stCen 16th Nov 2014 06:16


But don't listen to me, I don't know nuthin' about military aircraft.
FHruitloops,

We won't listen to you, nobody ever does... Your limitations are far greater than just military aircraft as demonstrated by virtually every one of your posts on this thread. Your arrogance is surpassed only by your ignorance. The only people following you around are the ones that want to put you back in the asylum. Unfortunately for us they probably have Wi-Fi there.
:rolleyes:

heli1 16th Nov 2014 15:46

Hmmmm....I thought the captain of the aircraft had the final say.The correct decision here would surely have been to abort and head for the nearest airport until the area was made safe,the traffic stopped and the barriers reinforced.

sandiego89 16th Nov 2014 19:08

Meh, I fail to see the severity of the crisis here. A heavy rotor craft kicked up a good dust storm. If they used the golf course, punters would likely be complaing about the evil, arrogant war mongers destroying a golf course or denying tax payers the use of the links.

The Sultan 21st Nov 2014 22:16

Tot,

The AH-1Z and the AH-64 are clearly superior to the Tiger and at least the 1Z and the older, but still superior AH-1W, can work in the maritime environment with no need to conduct major repairs after one short deployment.

The SH-60 is superior to the NH90, but very inferior to the V-22. Both can operate at sea with no serious degradation.

As to the Seasprite anyone had a better option.

Last time I checked Australia is surounded by water.

The Sultan


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