Armed Polite Society
Main Forums => The Roundtable => Topic started by: 280plus on November 22, 2009, 12:39:27 PM
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What do you think Leatherneck?
No link, probably Mil Times:
Flight decks buckle from heat in 10 minutes
By Andrew Tilghman - Staff writer
Posted : Sunday Nov 22, 2009 9:37:49 EST
Leaving an MV-22 Osprey’s rotors idling on a flight deck will create enough heat to melt and buckle the deck in about 10 minutes.
Repeated deck buckling will ruin the flight deck in about 40 percent of the ship’s projected life span.
And introducing the F-35 Joint Strike Fighter jump-jet variant will only add to the problem.
Those are among the issues cited by the Office of Naval Research as it seeks a modification for flight decks to better withstand and distribute the heat from the new aircraft’s exhaust and downwash.
ONR is seeking proposals on how to build a “flight deck thermal management” system that will help distribute the heat from the aircraft and keep the deck temperatures below 300 degrees.
Testing shows Osprey downwash can raise deck temperatures as high as 350 degrees.
“Currently there are no available solutions other than heavy structural modifications to mitigate deck buckling and thermo-mechanical deck failure,” according to a recent document seeking proposals from private companies, known as a broad agency announcement.
The new systems — which could involve a one-inch plate on top of the deck or a cooling system installed below the deck — will likely be installed in the Wasp-class amphibious assault ships and future America-class flattops, according to the ONR document.
The ONR announcement reveals the Navy’s challenges as it tries to introduce a new generation of aircraft with tilt-rotor and short-take-off-vertical-landing ability on ships designed for traditional helicopters.
The Ospreys, the military’s first tilt-rotor aircraft, create extraordinary heat and force when the nacelles are tilted upward and the rotors muster enough force to lift the aircraft like a helicopter.
The F-35B Lightning IIs that are expected to join the fleet in 2012 have a unique vertical-landing feature that turns the jet’s thrusters to face downward during landing and expose the flight deck to hot exhaust that could damage the flight decks.
Osprey’s downwash creates enough force to knock sailors and aircraft off the flight deck, according to a report from the Government Accountability Office.
Naval Sea Systems Command has not made any determination on the need for flight deck modifications, and potential solutions are still under consideration, NavSea spokesman Alan Baribeau said. Procedures used on the Osprey’s first at-sea deployment aboard the amphibious assault ship Bataan were effective and will be used again, he said.
WHAT’S NEXT
The Office of Naval Research’s proposed timeline aims to develop a flight deck cooling system by 2014:
• 2010: Award contract.
• 2011: Test materials to handle aircraft heat.
• 2012: Build a large-scale test panel.
• 2013: Conduct land-based testing.
• 2014: Install the Thermal Flight Deck Management system on a ship.
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In exactly one word familiar to one and all: oops!
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And it never occurred to anyone before now ...? ;/
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My first inclination is, hmmmm, how am I gonna cool that deck off? I could use a nice navy contract right about now. =D
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So how did they handle the Harriers?
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I don't think there was an issue with the Harriers because they exhaust to the rear when idling, whereas the Osprey with the rotors tilted is exhausting right onto the deck.
The solution until they get some sort of fix installed on the deck is probably just going to be a mandate stating that the engine will not be run with the exhaust pointed at the deck for more than X minutes.
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Idling, yes, but Harriers had their nozzles pointed straight down at least sometime during the flight regime, no?
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At best, this article has its facts wrong.
At worst, they'll need to revamp a lot of decks to keep up with newer aerospace tech. Such is progress.
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Idling, yes, but Harriers had their nozzles pointed straight down at least sometime during the flight regime, no?
I'll preface this by stating that I was not Navy, and that I never worked with Harriers or the V-22.
The Harriers did route exhaust down, but I think it was only for brief periods during take-off and landing.
The article states that
Leaving an MV-22 Osprey’s rotors idling on a flight deck will create enough heat to melt and buckle the deck in about 10 minutes.
I infer that the exhaust stream during actual flight operations is not the issue, the problem is when you have an aircraft cooking the same spot for an extended period of time.
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So what do they do when the Ospreys are idling at a fixed base? Runways are asphalt, and asphalt melts at a much lower temperature than steel ...
On the ships, it would appear (and therefore can't be) a fairly simple matter to add a surface layer with cooling tubes running under it, and just pump seawater through the tubes when the birds are sitting there idling. It could give an entirely new meaning to the term "Cool your jets."
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So what do they do when the Ospreys are idling at a fixed base? Runways are asphalt, and asphalt melts at a much lower temperature than steel ...
That's what I was thinking.
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So what do they do when the Ospreys are idling at a fixed base? Runways are asphalt, and asphalt melts at a much lower temperature than steel ...
Good question, Hawkmoon. I wonder what they do currently to avoid problems on asphalt ramps.
I'd imagine it's not so much of a problem on a concrete ramp. And taxiing on asphalt shouldn't be a problem as exposure is limited by the Osprey's movement.
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I read somewhere that the blast shield used by Navy jets when launched from a carrier are now using the same type of thermal tiles used by the Space Shuttle.....maybe they could try something along that line....
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So what do they do when the Ospreys are idling at a fixed base? Runways are asphalt, and asphalt melts at a much lower temperature than steel ...
On the ships, it would appear (and therefore can't be) a fairly simple matter to add a surface layer with cooling tubes running under it, and just pump seawater through the tubes when the birds are sitting there idling. It could give an entirely new meaning to the term "Cool your jets."
Concrete runways maybe? Sea water is not a bad idea but seawater has a bad habit of having things like barnacles and other ooky stuff growing in it that might clog said channels. Believe me, you haven't lived till you've had to "air lance" or punch out the tubes on a seawater cooled shell / tube heat exchanger. No telling WHAT might come popping out of there. Jellyfish for example, mussels etc. :O Recirculating chilled fresh water would probably be a better way to go. I forwarded the article to a friend of mine who s deeply involved in this kind of stuff, he says he's seen the documents and "it ain't pretty" so I have to assume the article is correct factually.
I made the cooling water suggestion AND the heat tile suggestion to him so I'm kind of pleased to see seeker came up with the same idea. Great minds and all... ;)
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So what do they do when the Ospreys are idling at a fixed base? Runways are asphalt, and asphalt melts at a much lower temperature than steel ...
On the ships, it would appear (and therefore can't be) a fairly simple matter to add a surface layer with cooling tubes running under it, and just pump seawater through the tubes when the birds are sitting there idling. It could give an entirely new meaning to the term "Cool your jets."
I suspect most runways are reinforced concrete, most times which is pretty decent WRT heat. Also, that concrete is in direct contact with the ground. That's a whole lotta heat sink.
The idea of working around such beasties on a metal deck does not sound like a fun job.
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I don't know why they are even bothering with this. Obama seems to think we don't need the F-22, so what makes the Navy think they will be anything different with the f-35? Pax Americana is a thing of the past. We won't have enough firepower to stop The Muppets from taking Manhattan. When Barney Fife gets done gutting the military, they are going to be wishing for the Carter years.
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Idling, yes, but Harriers had their nozzles pointed straight down at least sometime during the flight regime, no?
For L-class ships most all take-off is done in a STOL config, the Harriers deck run with the nozzles aft and near the front of the deck they rotate the nozzles to an intermediate position to facilitate take-off at a still to slow to really be flying speed. Landing, they achieve a hover about 10 ft above the deck and chop the throttle. Controlled crash. ;/ Most nervous I have ever been with my Inspector 12 stamp was when repairing and returning to service Harrier main struts. No mechanic wants to be the star of the mishap board. That landing gear takes a beating.
I read somewhere that the blast shield used by Navy jets when launched from a carrier are now using the same type of thermal tiles used by the Space Shuttle.....maybe they could try something along that line....
The JBDs are steel, some kind of paint on coating, but the key is a cooling system of water pipes running through the JBDs. The thermal tiles would be too fragile, remember aircraft get towed across the JBDs, sailors with tools and all that.
From my five years on an LHA and going through a shipyard to mad the ship to carry V-22s, they have worked through a lot of these problems. Our poor old ship they had to paint on the hangar deck where you could park them so as not to overstress the structure of what also happens to be the welldeck overhead. I try not to be too mean on the aircraft, mine is only the view of the field maintainer, and our own Pentagon insider is much more informed/enthusiastic on the project.
I just see what might become field sustainability problems, I'm sure my old shop still doesn't have their multi-million buck bender to make hyd lines for the beast. I understand that the wind limitations for shipboard flight ops are pretty iffy. Things take up a lot of deck space and if you want to spread the thing for maintenance then it is going to the flight deck, no room below, flight deck will then be a little impaired for flight ops and the weather better not be too iffy.
I think the thing would be much better served working from dry land. Boat ops eat a lot of space, lots of support equipment added to an already stuffed ship, etc. The extensive use of carbon fiber is great for increasing the usable load, fuel savings, corrosion resistance and all that, going to be a bear to fix in the weeds when Johnny Abdullah starts blowing holes in it. Same with the 5000psi titanium hyd. lines, and such. Like many of our newest aircraft it exists because Fed-Ex and DHL exist.
I'm 5 years carrier, five years L-class, 3 years helos tin bender, carbon fiber whacker, and hyd. mech. Don't really miss it, kicking the tires one a month on F-18s is now good enough for me.
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I think you may find that the problem they are complaining about is buckling. Steel expands quite a bit when it heats up. It causes the steel to buckle. Just like concrete roads do when it gets really hot sometimes.
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Whoa whoa whoa.... 5000 psi?!?! :O
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At best, this article has its facts wrong.
At worst, they'll need to revamp a lot of decks to keep up with newer aerospace tech. Such is progress.
The article has most of its facts correct.
And "revamping the decks for newer aerospace tech" is a more significant problem than you'd think. Ships have a long service life. They're not generally overly friendly to huge changes as stuff is very purpose built these days. Not saying it's possible, just an engineering nightmare.
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So, why not use a low-tech solution here?
A simple large diameter hose and pump that pulls sea water up, barnacles/starfish/jellyfish and all, and washes down the deck to keep it below 200 degrees. Consider it a Texas-sized patio misting system.
I understand we're dealing with a buttload of thrust and that thrust may not allow the water to get directly between the exhaust and the ship deck... but it'll be close. And moisture acts as a wonderful thermal conductor.
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Whoa whoa whoa.... 5000 psi?!?! :O
Not that uncommon, more standard is the 3000 psi systems like in my F/A-18Cs. My old helos were 1500 psi. The 5K system lets you have smaller, lighter hyd systems that do the same work as larger 3000 psi systems. Problem is that if a H-46 mech wandered into my shop and needed a line made I could pull out a piece of stainless, hand bender, sharpie marker, terminal hardware and have him on his way before the paperwork is finished. Maybe grab the portable perma-swage kit and go splice it into his existing line. Things just aren't that easy when you are playing with Titanium. The yardbirds actually installed another whole 20'x30' room in the overhead of my ship's hangar. Purpose? Just to house the damn bender for the tube.
Edit: The damn bender. http://www.pines-mfg.com/pdfs/media/om0707.pdf (http://www.pines-mfg.com/pdfs/media/om0707.pdf)
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So, why not use a low-tech solution here?
A simple large diameter hose and pump that pulls sea water up, barnacles/starfish/jellyfish and all, and washes down the deck to keep it below 200 degrees. Consider it a Texas-sized patio misting system.
I understand we're dealing with a buttload of thrust and that thrust may not allow the water to get directly between the exhaust and the ship deck... but it'll be close. And moisture acts as a wonderful thermal conductor.
Deck already fully rigged with flush deck sprinklers for fire fighting and CMWD. Keep your salt water away from my corrosion magnet airplanes. kthxbai
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Back from the river, checking in late...
This has been known for years--literally. We first discovered it when an
Osprey was kept sitting on the deck (I think it was Bataan) for about 45
minutes ready to launch with both engines running. As it stayed in one spot the deck heated and warped. After the Osprey departed and the deck cooled it straightened itself again when cool. So immediate workarounds were NOT to idle an Osprey in one spot for (I think) 20 minutes; if they're going to be longer, they shut down the right engine. That was several years ago.
The worry, long-term, is that (a) the deck plates will scinter--undergo
molecular changes- with many cycles of heating and cooling; and (b) the
spaces underneath some spots on the deck may have either combustible
material or stuff that doesn't handle heat well.
The medium-term workaround has been to fabricate hot-plates that look like a metal web on wheels that deck handlers wheel into place under the V-22's right engine for extended engine runs.
This current project is DARPA asking for proposed long-term solutions and
I'm sure it will be a beauty like seawater pumped through under-deck
channels to carry off the heat or something. I've no idea what the Navy will finally settle on, but I'm sure it will be expensive.
Many have commented that "this will be even worse for the Joint Strike
Fighter." Not true: the JSF, like the Harrier, points it's nozzles (exhaust)
downward for brief periods during takeoff and landing. While the total heat exhausted is much greater than the Osprey emits, it's only for brief
periods, so no problem.
TC
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I've no idea what the Navy will finally settle on, but I'm sure it will be expensive.
Sounds like the Navy I know... :lol:
One error on my part. We wouldn't find jellyfish in the heat exchangers, they'd get caught in the strainers upstream and we'd find them in there when we cleaned them. No telling WHAT you might find in the strainers. Barnacles and mussles however would find their way in as seed and grow in the tubes. When I say "air lance" I mean we would insert a rubber plug at one end of the tube(s) and we had a "gun" that would fire an air slug in behind it and shoot the plug through to the guy at the other end who is holding a cardboard box to catch the slug. It was a bit messy. Probably still is. =D
Apparently they are looking at modified JBDs as a solution but nothing is settled. Do they use seawater in those?? If they do is there a way to clean the debris out? Like opening them up?
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So, why not use a low-tech solution here?
A simple large diameter hose and pump that pulls sea water up, barnacles/starfish/jellyfish and all, and washes down the deck to keep it below 200 degrees. Consider it a Texas-sized patio misting system.
I understand we're dealing with a buttload of thrust and that thrust may not allow the water to get directly between the exhaust and the ship deck... but it'll be close. And moisture acts as a wonderful thermal conductor.
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Uhm. No? Aircraft no like salt water. It'd be the equivalent of someone rubbing you with Sarah Brady and/or Nancy Pelosi.
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And we all know how painful THAT would be... :O
:laugh:
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There's a fleet of former USAF WC-135s sitting in the boneyard with massive lower wing spar and wing box corrosion, courtesy of a bunch of guys who liked to fly them at 300ft over the Pacific wavetops.
Saltwater and aircraft aluminum just don't like each other. ;)
Curious why the Ospreys are idling so long. Doesn't say much for sortie generation times, if you have to pad it by that much...
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Waiting for other assets who were having trouble getting airborne (hint: sounds like a tomato-based veggie drink). =D
TC
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Waiting for other assets who were having trouble getting airborne (hint: sounds like a tomato-based veggie drink). =D
TC
That just ain't right. :laugh:
Wonder if someone will make something to escort 'em Ospreys around. You know, with guns and such. :lol:
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Normally I'm pretty up on the various aircraft and their designations, but the V8 reference when right over my head. Any clues?
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Question: I thought the V-22 was a rotor aircraft as in the rotors suck air from above and blow it downward. What hot exhaust is this referring to? All I can think of is engine exhaust in the center maybe.
Also, they mentioned the wind force is enough to throw people around. Why is that worse than the helicopters? Size of the rotor?
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It's a turboprop. There is a turbine engine in each nacelle, exhausting out the rear of the nacelle.
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I was thinking AV8(B) Harrier, myself. =D
The Osprey runs two hot-exhaust turboshaft engines, not unlike the Hercules and Orion. It's just that the aircraft is propelled by the combined noise of both the propeller and turbine exhausts, offering some redundancy. ;)
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I was thinking AV8(B) Harrier, myself. =D
Oh yeah... I feel really stupid at this point.. I have a cousin in-law (if that is a real relation) who is a harrier pilot and was the XO of a squadron until last year. He is currently doing something at the Pentagon, not sure what and is waiting for his CO slot. He got to punch out of one a few years ago when the engine cut out a couple of miles short of the ship.
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Do Harrier jets use a turbofan engine ???
If so, the downward thrust would be mostly "cool" air.
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Uhm. No? Aircraft no like salt water. It'd be the equivalent of someone rubbing you with Sarah Brady and/or Nancy Pelosi.
Gah! The idea gives me the willies.
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It gives me the Brady's. :'(
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This is easy.
Put a big ceramic (silica or alumina) or aerogel sheet, maybe 8'x8' on a set of rollers and roll it directly under the thermal wash. Once in place, either it locks, ties, or is otherwise settled in place. Leave thermal ablation pad in place while aircraft is at idle. Remove thermal ablation pad before launch. Remove pad to safe area to dump excess heat.
No need to invest in high tech, high dollar thermal management systems. If the space shuttle tiles can soak up heat from re-entry, similar tiles should be able to protect against a little thermal wash.
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The thermal tiles used on the space shuttle are very fragile.
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And they break easy too... =D
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The thermal tiles used on the space shuttle are very fragile.
And we rarely heavily mist the Space Shuttle with sea water.
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The tile idea is being used now, although in the form of a steel grid, not ceramic. But deck swabbies do not like the need for extra gear on the flight deck. DARPA is soliciting ideas for a built-in solution.
This made me LOL:
the aircraft is propelled by the combined noise of both the propeller and turbine exhausts
=D
TC
ETA: The rotor wash from the Osprey is more intense than any rotary wing aircraft in the inventory. A 25-ton aircraft supported in a hover by two 38-ft diameter proprotors generates considerable wind. But not at the core of the downwash where the jet exhaust is.
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Who do I contact in terms of an idea? A cheap one too. =)
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Leatherneck, old joke amongst us crewdawgs.
Q: What makes an airplane fly?
A: Noise. If the noise stops... ;)
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So in your case noise is a good thing. :lol:
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Yup. In fact, the more noise, the better, be it 4 or 8 engines. =D
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Ooooo, 8 engines... Want! >:D
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Okay, back in the day, most of you know I was a Marine ATC. I was stationed at a Harrier base (Yuma).
I don't have any experience working Ospreys or JSF's, but I'll tell you a few things about the AV8 and the USMC/USN infrastructure.
Yes, a Harrier will melt asphalt, even just conducting a VSTOL with no "idle" time. Seen it first hand.
Most airports have concrete taxiways and landing thresholds. Most even have at least one concrete runway. The AV8 can land fine on Concrete. Anything that can handle repeated AV8 ops can certainly handle having an osprey nacelle pointed down at it.
In the long run, if this becomes a problem, so be it. Replace and redesign. The OV22 represents progress :cool:
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Did you guys have to run to Autozone for tar remover every time they landed on Asphalt? [popcorn]
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Yeah, I knew only part of the Harrier's ducted thrust was cool air. The rear two nozzles are the hot end of the turbine core's exhaust, and the front two are bypass air from that big Rolls Royce Pegasus compressor stage, from what I could remember.
The USAF had issues with Harriers visiting bases, no VTOL ops from asphalt taxiways. They got all bubbly and gooey for the next plane that taxied through... :O
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I'm imagining a stuck Cessna right now. :laugh:
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Leatherneck, old joke amongst us crewdawgs.
Q: What makes an airplane fly?
A: Noise. If the noise stops... ;)
That big fan also keeps the pilot cool. Stop it and watch him sweat!
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Again, you think they would've learned from the Harrier's hot exhaust:
http://www.wired.com/dangerroom/2009/06/hot-breathing-osprey-sparks-five-acre-fire/
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Again, you think they would've learned from the Harrier's hot exhaust:
http://www.wired.com/dangerroom/2009/06/hot-breathing-osprey-sparks-five-acre-fire/
I like this comment:
Posted by: ibnsuleiman | 06/5/09 | 9:38 pm
Like hovercraft and autogyros, tilt wing/rotor aircraft are destined to be ideas that looked good at the time but end up with very limited practical applications, the compromises involved in trying to make them do two separate jobs result in an expensive vehicle with limited capability.
Now we find they can’t be flown into an area where the surface is flammable meaning one guy with a jerry can could potentially sabotage a landing site making them unsafe for hostile environments.
They are hardly new, this programme has been running since the mid 1980s and similar aircraft have been under development since the mid 1950s.
=D Too funny.
Low tech circumvention of high tech transportation.
Allow me to posit this:
What enemy might we face in the next 10+ years that would be more vulnerable to an Osprey than a Blackhawk...that merits investing in retrofitting dozens of ships and/or the proposed Osprey fleet? How are Osprey superior when utilized in police-action scenarios like the GWoT we're involved in right now, in comparison to a conventional rotary wing craft?
I'm not opposed to any aircraft... I think they're all cool. Osprey sounds neat. But how is it superior for inserting/extracting Marines from the field, and how well does the significant investment to solve the problems, reward us?
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Why Harriers don't overheat deck plating:
http://209.157.64.200/focus/news/2388318/replies?c=31
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A-kaak A-kakk... got dust? :O
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The USAF had issues with Harriers visiting bases, no VTOL ops from asphalt taxiways. They got all bubbly and gooey for the next plane that taxied through... :O
USAF? I thought it was the USMC that flew Harriers (along with the Brits, of course).
http://en.wikipedia.org/wiki/Harrier_jet
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The Osprey's major benefit is airspeed.
That reduces transit/deployment time, since it's not beset with the max speed limitations imposed upon conventional rotary-wing aircraft.
However, it does that at the expense of other aspects of the flight envelope, as Leatherneck alluded to.
I'd never even heard of "vortex ring state" until the Osprey racked up a few training accidents. It's got to have one seriously heavy load on those rotors while in helicopter mode. :O
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USAF? I thought it was the USMC that flew Harriers (along with the Brits, of course).
http://en.wikipedia.org/wiki/Harrier_jet
Correct, but there are a lot more Air Force bases than there are Marine bases. It would not be totally uncommon for Marine aircraft to do a pit stop or cross training at an AF base.
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The first jump jet pilot:
Roger T. "Race" Bannon is a special agent / bodyguard / pilot from Intelligence One. Governmental fears that Jonny could "fall into the wrong hands" resulted in the assignment of Bannon to guard and tutor him.[8] Race was born in Wilmette, Illinois, to John and Sarah Bannon.[9] He is stated to be an expert in judo, having a third-degree black belt as well as the ability to defeat noted experts and even sumo wrestlers. Race Bannon was voiced by Mike Road. The character's design was modeled on actor Jeff Chandler.[10]
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What enemy might we face in the next 10+ years that would be more vulnerable to an Osprey than a Blackhawk...that merits investing in retrofitting dozens of ships and/or the proposed Osprey fleet? How are Osprey superior when utilized in police-action scenarios like the GWoT we're involved in right now, in comparison to a conventional rotary wing craft?
An enemy 500 miles away, for starters. A V-22 can carry 24 combat-equipped Marines 500 miles in two hours and return for more in the same time. The higher speed/range/payload capabilities of the tiltrotor are its main advantages. But as in all compromise aircraft designs, to get something, you give up something.
TC
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Jack,
One forgets that USAF bases don't exclude visiting Army, Navy, USMC, Coast Guard, NASA, State Department, NOAA, and other governmental aircraft from using the facilities.
On a given day, you could see all sorts of different aircraft from all branches on a USAF parking ramp. We didn't discriminate. =D
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The EM club must be interesting on a Saturday night. :O
I DO recall drinikng at the AFB on Guam a lot because it was nicer than ours. ;-)
Can't remember the name. Or maybe it was Naval Air. The CRS is kicking in again. =|
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Wonder if someone will make something to escort 'em Ospreys around. You know, with guns and such. :lol:
Why not mount guns on the Osprey?....worked for the Hueys....
And we rarely heavily mist the Space Shuttle with sea water.
....and yet we launch the things near an ocean.... ;/
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They have worked with gunpods and the like, from my limited reading the problem is weight and controlling the guns so they can't be fired into the rotors at any given angle, though i think that shouldn't be a huge technical issue. Make 'em remote operated from a pilot headset and have a cutoff when the airframe is endangered.
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They've tried that Carebear, with mixed results. From the cabin point of view, which is where you would mount guns, in helo mode the nacelles are a huge blockage right outside and abeam. In airplane mode, the big proprotors present an impenetrable wall at the forward cabin door. They've put a tripod-mounted SAW on the tail ramp and that's useful for the rear hemisphere.
EADS developed a palletized turreted gun system that gets snugged up in the belly "hellhole" but the field of fire allowed by the software means basically you can shoot people in the top of their heads, but not much to either side.
This may be one of those unsolvable design problems that is not fixable in this first-generation tiltrotor.
TC
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An enemy 500 miles away, for starters. A V-22 can carry 24 combat-equipped Marines 500 miles in two hours and return for more in the same time. The higher speed/range/payload capabilities of the tiltrotor are its main advantages. But as in all compromise aircraft designs, to get something, you give up something.
TC
Problem with that is no guns. You need another platform to provide escort when the Osprey is 500 miles away from base. Don't worry, you'll have that project on your desk in another 5, 10 years.
They have worked with gunpods and the like, from my limited reading the problem is weight and controlling the guns so they can't be fired into the rotors at any given angle, though i think that shouldn't be a huge technical issue. Make 'em remote operated from a pilot headset and have a cutoff when the airframe is endangered.
Weight wasn't the biggest thing per se. Integration was. Weight just made integration extremely problematic. Basically, the nose is the only part of the Osprey you can 'easily' mount a big honkin gun. Problem is, there's already a lot of kit there to begin with. You have to bolt on the nose gun (without hitting any of the existing stuff), route the wires and ancillary kit (without hitting any of the existing stuff), and integrate it into the aircraft's existing systems (without FUBAR'ing any of the existing stuff).
Folks looked at it and said "too expensive", then dropped the requirement. So the sole defensive weapon is a M240 mounted in the rear. I suppose to cover LZ's when landing or taking off?
Why not mount guns on the Osprey?....worked for the Hueys....
....and yet we launch the things near an ocean.... ;/
1. Can't, except for the M240 on the tail.
2. Near is a flexible word. We launch the the Space Shuttle more than a hundred meters from the ocean, and they are stored in buildings when not being launched. OTOH, Navy aircraft and ships tend to be quite a bit closer to the salt water and often for longer durations.
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Wonder if someone will make something to escort 'em Ospreys around. You know, with guns and such.
They do. It's called an A-10. Low, slow, and a buttload of ordnance. =D
Y'all ever notice how funny it is that a given airframe will get past the design stages and into A or B model production, and THEN folks start wanting to hang extra crap on it. They couldn't be bothered to add the guns and microwave ovens during the blueprint phase, no...
If I were Bell-Boeing-Vertol? You want an ACV-22 gunship? Fine, but you're gonna pay extra. It can be done, witness the AC-130, but after-the-fact it'll always be a royal pain in the posterior. Getting all bent out of shape because one can't hang guns on a CV-22 simply means that those who wanted such amenities never brought the concept forward during the design phase, or the big giant heads deleted the requirement at some point afterwards.
Hell, if I could've had Sparrows or Sidewinders hanging off my WC-135, those Nork MiG-29s would never have had the big brass cajones to mess with us in the Sea of Japan a few years ago. ;)
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Sounds a lot like building a new house. I know a guy who had these poor SOBs rip out and redo his bathroom layout 3 times. THEN he wanted to know what was taking so long and why is it so much more money. Aren't life's parallels a hoot? :lol:
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They do. It's called an A-10. Low, slow, and a buttload of ordnance.
The Warthog got my vote, too, when I read that comment.
How many times has the Warthog been declared "obsolete" now? Seems to be one of those platforms that's been obsolete for so long that everyone just plain forgot to build anything to replace it ...
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Modify the nacelles. Put a remote-operated gun (mod. SAW? something light) in a pod on the outside of each nacelle. Nose gun for arc forward of rotors (like the AH's).
The nacelle and nose guns can be physically limited to not fire into the rotor arc.
In forward flight the nacelle guns would have full movement to aft/up/down/ and starboard or port depending (quarter sphere effectively), in hover that becomes forward/aft/down and strbrd or port.
Being remote with a camera the system can automatically change orientation to be comfortable for the operator in the aircraft. For a mass landing you'd only need a gunner on the "outside" gun leaving a crew chief free to do his job, on a Pave-type variant add another gunner station (which would be a modular plug-in station inside the aircraft).
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(https://armedpolitesociety.com/proxy.php?request=http%3A%2F%2Fwww.members.shaw.ca%2Fdavid.p.z.888%2Fstar_wars%2Fpics%2Frepublic_gunship.jpg&hash=199c28947e6927145b01d8bb950a8ea073692931)
http://www.members.shaw.ca/david.p.z.888/star_wars/pics/republic_gunship.jpg (http://www.members.shaw.ca/david.p.z.888/star_wars/pics/republic_gunship.jpg)
Maybe we could hang some of these ball things on it?.....
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Tell me again how many A-10s are part of the MEU, MEB, & MEF?
In reality, they got the AV-8B and maybe squiddie F18s. Nothing that gets low & slow with lots of guns. Or anything that will loiter right nearby for a goodly amount of time.
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Sounds like a planning problem at the Puzzle Palace, to me.
It's not as if the A-10C doesn't do CAS. USAF assets don't have to be administratively attached to an MEU or any other Marine sortie to provide cover, last I looked. They just have to be tasked. See Puzzle Palace reference, above.
There are plenty of Joint Chiefs-directed multi-service ops out there, simply pick and choose. I flew joint Navy/USAF ops with minimal spacing between P-3C Reef Point, WC-135B Constant Phoenix, HC-130N, and RC-135S Cobra Ball assets all working over the same targets, and that was nigh unto 15 years ago. I was the USAF mission commander on the Navy P-3C, no less. Obstacles? What obstacles?
Hanging a plethora of extra guns on an airframe that's already at weight limits? Not without something else getting deleted, I'm afraid.
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Why wouldn't the F-35 or Harrier fill in the escort duty? I seriously doubt you are going to fly Ospreys down onto Omaha beach under fire without support. If you are going to land troops 500 miles away, you have the flexibility to choose where to drop them. I thought the whole idea of them was to put troops on a beach so that waterborne craft could move in on a controlled beach.
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Can A-10's operate off carriers?
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Not without carrier-modified landing gear and a proper Navy tailhook, Balog.
Catapult launches and trap wire landings induce their own stresses on carrier-based aircraft.
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Interesting. So if they need support when they do the task that is their primary justification (long range insertion) and the only suitable craft to do this can't launch via carrier.... why are we fussing about getting them to launch off carriers? ???
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Why would you say the only aircraft that can support them is the A-10? Support them from what? If there is enemy armor in the landing zone, I doubt you would send in any aircraft to land. If you are concerned about enemy fighters, the A-10 is hardly ideal.
Now if you are talking about supporting the Marines on the ground after the V-22 flies away, that is another story and that can be done with a number of different aircraft.
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I won't claim to be an expert, but for prolonged CAS the only craft I know of that does it well is the A-10. All the other fast movers aren't that great at it.
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Depends on the mission requirements, Balog. I wasn't the one saying it had to launch from a carrier.
If there's a target within range of an airstrip-launched and air-refuelable A-10 variant, CAS via that method would be mighty fine.
Outside the sortie range of an A-10? Then you switch to other platforms, and modify the mission accordingly.
Send a CV-22 or two back to depot, rip everything out that isn't bolted down, and fix a minigun in the nose to create that ACV-22 dedicated gunship. Then use it as a dedicated tiltrotor escort. ;)
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I won't claim to be an expert, but for prolonged CAS the only craft I know of that does it well is the A-10. All the other fast movers aren't that great at it.
I'd add the AC-130's to that list...esp. in the loiter time department.....
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The Harrier will have to do the long range CAS if other services are not around. No long loiter, but it does have an IFR probe. The belly mounted 25mm gun pack is some serious unhappiness coming from the sky. AH-1W and AH-1Y can handle closer stuff. If I was in charge I'd want a tailhook on an A-10, just deck launch them ,no cat needed most likely. Beyond CAS ashore, the trick would be to penetrate or expend a surface combatant's point defenses. Then the GAU-8 shows up, burn to waterline ensues. I think Tom Clancy did that in one of his books. Anyway, I wouldn't want to be a frigate commander reloading my point defenses after a Harpoon attack and see an A-10 appear inbound. I think I'd rather take my chances with the cruise missile.
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I am aware of joint operations and have modeled current and proposed future USMC and joint C4ISR for this sort of thing. I am for it every day of the week and twice on Sundays.
Thing is, I specifically mentioned the jarhead ME* because they are supposed to be everything rolled up with a nice bow on top: infantry, armor, arty, FW aviation, airmobile, etc. All by itself, it is supposed to go anywhere in the world and complete a mission appropriate to its size:
MEU-BN infantry, ~BGDE overall
MEB-BGDE infantry, ~DIV overall
MEF~DIV infantry, ~CORPS overall
There are places where Bad Things Happen on short notice that are out of range but a very, very few USAF assets (B1, B2, B52).
Now, relative to the Army, a lot of USMC "arty" is located on its CAS and jarhead pilots know why they exist: to support the rifleman on the ground. So the ME* have that going for them.
Thing is, this whole airmobile thing has been done for a while and Army & even AF knows how it is done right. Doing it right includes (among other things) having munition platforms with flight characteristics roughly equivalent to the troop transports. They stick close and are right there down low near the LZ, keeping an hairy eyeball out. No delta-winged fast mover thousands of feet up in the air is going to provide supporting fires as quick or as effective. I doubt even an A-10 could be as responsive.
The jarheads aren't stupid and they know this. I bet the original plan called for a certain proportion of Osprey gunships, but they got axed. Now, they've got troop transports that are hella fast and their Cobra gunships are too fat & ugly to go to the dance with the hot & sexay Ospreys. So, the Harriers get the job. Interesting and capable aircraft, but it is no gunship.
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A gun has been an operational requirement on the Osprey forever. I remember asking a long-ago PM how the development of the gun was coming along and he responded: "I consider the gun an unfunded mandate." That was nearly two decades ago, and it never really changed; there was never enough money on the program (or maybe enough credible schemes to demand funding) to get an integrated gun solution.
The original "concept" of a nose turret with full-coverage gun inside always caused me a headache. Who controls it? If it's the pilot, he can only see targets on the left side. Copilot? Same problem on the right. What with the V-22 maneuvering, how do you handle crew coordination as the target passes the nose?
"I've got it."
"What? The gun or the aircraft?"
"No, the aircraft. You've got the gun."
"Where'd the target go?"
I dunno the best answer... ???
TC
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Have someone operate the gun remotely by satellite etc. or AWACS is it? The flying saucer plane thingy. I believe it does have the thing that goes up. lol...
Aren't they doing that with some umanned stuff already? Combine it. We'll start a "Save the Osprey" fund here on APS for the funding. I got the first dollar. =D
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What with the V-22 maneuvering, how do you handle crew coordination as the target passes the nose?
You know, I may be on drugs here, but maybe bulb-shaped, B-17-type turrets somewhere on the craft, manned or unmanned?
[Manned would be far more awesome, but unmanned would be far more practical, I suspect].
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The AV8 is more than capable of providing the necessary CAS. And anyone who doesn't think the average Marine Aviator will stick that thing right down in the weeds to provide serious hurt is seriously mistaken. I've seen what an AV8 can and will do in training, including training to call CAS missions.
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The AV8 is more than capable of providing the necessary CAS. And anyone who doesn't think the average Marine Aviator will stick that thing right down in the weeds to provide serious hurt is seriously mistaken. I've seen what an AV8 can and will do in training, including training to call CAS missions.
How much armament can a Harrier carry, and what kind of linger time do they have? Not being snarky, I'm actually curious.
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How much armament can a Harrier carry, and what kind of linger time do they have? Not being snarky, I'm actually curious.
GAU 12 pod with 300 rounds, plus 7 hard points. Typical CAS armament would be some zunis, mavericks and 500 pounders.
Wiki has an accurate run down
http://en.wikipedia.org/wiki/AV8B#Specifications_.28AV-8B.2B_Harrier_II_Plus.29
Loiter depends on a number of factors, but with a 1400mi range it can easily keep up with an osprey and stay on station long enough to provide support.
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Back in my early Navy days the country was in its bomb Bosnia stage. Then a little later it was Kosovo, another cruise, another story. I watched flight ops a lot then, young and trying to learn. Our ship carried 3 F-18 squadrons, 2 Navy and one Marine being the VMFA-312 Checkerboards. Most of the missions there were CAP and dismantling anything dumb enough to turn on its radar. The planes would typically go out with a couple of GBUs, a few HARMs, and standard defensive armament. Watching recovery the Navy Hornets would bring back a missile or two, maybe part of their bombload. Then here would come a -312 Hornet. Racks empty, trail of gun residue down the aircraft from nose to tail. Surprised they didn't figure out how to get their wingtip AIM-9s or droptanks on target. :laugh: Marine pilots think different, AKA correctly, when it comes to ground attack. The Harrier will do fine until the JSF gets on the scene.
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I wonder how many Harriers are left in the USMC inventory. It has been quite a while since McDonnell built any. I wonder if there is any active Harrier assembly line left in the world. I don't think the British or Spanish are buying any more.
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F35's will be replacing the Harrier, IIRC.
Another angle to consider is the entirity of the strike package. If you need the cobras, the OV22 flies in with the Cobras. Cobras loiter on station while the OV22's go back to get another load. Turnover time for the OV22 would certainly be faster than a good ole frog or '53. Harriers (and eventually, the F35) provide overall coverage for the entire operation.
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Another consideration is that if there is a beachhead established Marine aviation excels at quickly organizing FARPs, Forward Arming and Refueling points. The Cobras can then get gas and moar ammo 10 minutes from the fight while the Osprey is going to get another load.
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Another consideration is that if there is a beachhead established Marine aviation excels at quickly organizing FARPs, Forward Arming and Refueling points. The Cobras can then get gas and moar ammo 10 minutes from the fight while the Osprey is going to get another load.
What he said. Part of my old job was setting up a FARP. With just a couple thousand feet of bare ground, we could be landing and launching C130's within minutes. Fuel bladders and ammo arrive, cobras land and get rearmed, and the op continues.
Its all a well orchestrated ballet of death.
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Another consideration is that if there is a beachhead established Marine aviation excels at quickly organizing FARPs, Forward Arming and Refueling points. The Cobras can then get gas and moar ammo 10 minutes from the fight while the Osprey is going to get another load.
That is sort of what I was thinking. If the operation is coordinated, the Marines on the ground are not operating alone very long. The Marines have hovercraft and landing craft they can bring in close to provide more support. Once the initial attack/incursion is underway, the amphibious carrier is moving in closer with the chopper support also.
The other point is if the Osprey has weight limits and such, how will it carry enough armament to make any difference in a CAS role? It isn't going to be able to carry the armament and ammo load of those transport aircraft. I don't know if it would be as maneuverable as a Cobra or A-10 over the target and it may not be as rugged taking fire. You can't turn everything into a flying tank.
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Couldn't we just use gun cameras/sensors and virtual HUDs?
The gun operator doesn't need to be able to see the target with his eyes, he needs to see what the camera on the gun sees, which is a heads up display gunsight with all sorts of magic vision stuff (IR and thermal?) integral. So give it to the co-pilot on the nose or even a crew chief/gunner in the fuselage. Same with the "wing" guns.
A feed system for the nose wouldn't be hard to rig up, hell the magazine could be a modular pod on the belly, and a "gunship" or spec-ops variant won't have a weight issue because it won't be carrying as many (or any) troops, drop even just a squad and you've saved over a ton in mass and cube. A transport version won't be on the ground long and can reload when it goes back for the next wave, if armed at all. Nacelle guns would be tricky to feed from the fuselage or wings but could also have modular ammo packs and be saved for "point" defense on the ground.
I'm no engineer but this doesn't seem like a huge issue in theory and the mechanics don't seem insurmountable.
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The original "concept" of a nose turret with full-coverage gun inside always caused me a headache. Who controls it? If it's the pilot, he can only see targets on the left side. Copilot? Same problem on the right. What with the V-22 maneuvering, how do you handle crew coordination as the target passes the nose?
"I've got it."
"What? The gun or the aircraft?"
"No, the aircraft. You've got the gun."
"Where'd the target go?"
I dunno the best answer... ???
Simple.
You farm it out to that high school kid who built the robotic airsoft gun and let him make something that's small enough to fit and fully mission capable, for about $1200 and a sack full of Big Macs.
http://www.youtube.com/watch%3Fv%3DRxBa5bQfTGc
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I'll fund one of the Big Macs. That's nearly 400% of my original budget though. Hmmm, already the price is going up. :'(
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As far as the fuel-for-escorts goes, the V-22 has a relatively new capability to be a ground refueler for escort Cobras, other Ospreys, or ground combat vehicles like tanks and MRAPs. Hot refueling at a FARP of your choosing has been demonstrated and actually used in The Sandbox. Handy.
Helo escort has been part of the Marine light attack mission forever. I've flown more than a few such missions in A-4s, and the Harriers picked it up along with the rest of the light attack role. The fast-movers simply set up an overhead orbit that slowly progresses as the helos move to their objective. The whole package can be self-controlled or coordinated by a FAC/TACA.
TC