V22 Osprey discussion thread Mk II
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The V-22 is not a helicopter, all vertical lift aircraft are by necessity thin skinned and as light as possible, a 23mm gun is by no means a pea shooter.
There may be screw ups in the recent CV-22 mission abort, but I haven't seen anything that indicates it was an inherent fault of the V-22 design.
I would really prefer the DoD invest in Sikorsky's X-2 technology, but come on if you fly over a ZU-23 and get hit, even an A-10 would likely have problems afterwards.
There may be screw ups in the recent CV-22 mission abort, but I haven't seen anything that indicates it was an inherent fault of the V-22 design.
I would really prefer the DoD invest in Sikorsky's X-2 technology, but come on if you fly over a ZU-23 and get hit, even an A-10 would likely have problems afterwards.
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Sans, I'm not getting it. A force is being applied to a structure that is designed to handle the ensuing stress do to cross sectional area and shape. You then remove a piece of that structure with a bullet, the remaining structure can either handle the increased stress or it can't. What does the amount of strain have to do with it? I also don't get your point that thee X-2's system is more highly strained, stressed yes after all that's the point of flap and lead/lag hinges. Not trying to be a prick, just trying to understand you point.
As far as ballistic tolerances planned, I really doubt they have a solid answer to that at this point.
As far as ballistic tolerances planned, I really doubt they have a solid answer to that at this point.
Thread Starter
It was always my understanding that the ballistic tolerance of a rotor blade was a function of the robustness of the structure. A wide cord blade would be more balistically tolerant than a narrow cord blade. The trade off becomes one of ballistic tolerance versus ballistic susceptibility. i.e. What are the odds of hitting a narrow cord blade versus accepting a hit on a wide cord blade designed to survive the hit. This is where number of blades comes into the equation. The Blackhawk, Apache and Boeing YUH-61 UTTAS all used four bladed rotor systems with relatively wide cord blades in an attempt to achieve a balance between maximum ballistic tolerance and performance. I am sure that John Dixon could add to this discussion.
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Sans, my degree in engineering has spent the last 12 years unused, so I have no doubt things have gotten murky. Besides that, I never got into dynamic loading very much being more a fluids and thermo type. That said, I think I get your point better now, thank you for the reply!
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Altitude Performance
Hi Guys ,
Does anyone have any details of the altitude performance of a V-22 ?
For eg ...if one takes off from an airfield at 500 ft Amsl 35 C and were to hover OGE / hover IGE at ISA + 20 at 15000 ft 200 NM away and return to the same airfield .
Just wondering if it can really get some payload ??!!
Does anyone have any details of the altitude performance of a V-22 ?
For eg ...if one takes off from an airfield at 500 ft Amsl 35 C and were to hover OGE / hover IGE at ISA + 20 at 15000 ft 200 NM away and return to the same airfield .
Just wondering if it can really get some payload ??!!
Thread Starter
V-22 guide book
Prehar,
The short answer is NO. The following is a link to the Boeing V-22 Osprey guide book that includes a HOGE chart.
http://www.boeing.com/ospreynews/201...010_179638.pdf
The short answer is NO. The following is a link to the Boeing V-22 Osprey guide book that includes a HOGE chart.
http://www.boeing.com/ospreynews/201...010_179638.pdf
Thread Starter
Ref. Heavy Lift Helicopters SK-65 Flight Manual
The Sikorsky CH-53D is capable of hovering IGE at a ten foot wheel height at ISA +20 at 15,000 feet up to almost 32,000 lbs. At 95şF and 15,000 feet it still has the ability to hover IGE at 28,000 ft. With an empty weight of 23,000 lbs that leaves very little for payload.
Yes Jack those are HIGE numbers, I was referring to HOGE since you referred to a HOGE chart in the Boeing booklet. I dont think anything I know of can hover out of ground effect 15,000 ft @ 95F
Back to prehar's question:
India sizes up V-22 Osprey - 1/18/2012 - Flight Global
Back to prehar's question:
The V-22 would be well suited to operations along India's vast Himalayan frontier, where high altitudes and long distances hinder helicopter operations.
At last year's Paris and Dubai air shows, Osprey representatives made much of a mountain rescue mission in June 2010 conducted by two US Air Force CV-22s. The aircraft flew a 1,290km (700nm) round-trip at 15,000ft (4,570m), landed amid mountainous terrain in dust storm conditions, collected 32 personnel and returned to base.
At last year's Paris and Dubai air shows, Osprey representatives made much of a mountain rescue mission in June 2010 conducted by two US Air Force CV-22s. The aircraft flew a 1,290km (700nm) round-trip at 15,000ft (4,570m), landed amid mountainous terrain in dust storm conditions, collected 32 personnel and returned to base.
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Mr. Carson,
I think you've got a feet for pounds issue on the 28,000 for the CH53.
A 28,000 feet, 95F test would require a very warm day in the Karakoram.
SansAnhedral,
Is that flying to the mountains at 15,000ft, or landing amongst the mountains at 15,000ft? Landing at 9000ft would be rather easier.
32 guys must weigh 6000lb, so even with maximum extra tanks that only makes it to a 500nm radius from the brochure, against just over 600nm empty, so presumably that rescue must have been air-refueled, and the take off and landing in the mountains could have been almost empty of fuel.
I think you've got a feet for pounds issue on the 28,000 for the CH53.
A 28,000 feet, 95F test would require a very warm day in the Karakoram.
SansAnhedral,
Is that flying to the mountains at 15,000ft, or landing amongst the mountains at 15,000ft? Landing at 9000ft would be rather easier.
32 guys must weigh 6000lb, so even with maximum extra tanks that only makes it to a 500nm radius from the brochure, against just over 600nm empty, so presumably that rescue must have been air-refueled, and the take off and landing in the mountains could have been almost empty of fuel.
Brett, thats a dubious number, most publications list the CH-47 service ceiling around 18,500.
In any case, this is a good discussion of payloand and range at MSL to 3000':
http://skinnersgouge.com/uploads/2/8...5-09_rev_f.ppt
In any case, this is a good discussion of payloand and range at MSL to 3000':
http://skinnersgouge.com/uploads/2/8...5-09_rev_f.ppt
Last edited by SansAnhedral; 31st Jan 2014 at 12:08.
Way back when we had this discussion about Hover Performance and the Osprey did not compare to the 47D/F or 53E for payload vs. altitude. When considering OEI performance in the Hover...the Osprey is really lmiited compared to the other two aircraft.
The design of the various rotor systems account of that.
Comparing Service Ceilings of a Helicopter to the Osprey is an Apples to Oranges comparison unless you limit the Osprey to operating in the "Helicopter Mode". Such discussions should make a balanced comparison and not one tilted towards one or the other of the designs.
One cannot expect a Helicopter to perform at altitude in the cruise as does the Osprey.
Likewise we will not ever see an Osprey land on Everest as a helicopter has done or set an altitude record like the Lama did.
I doubt we shall see a Helicopter cruise as fast as the Osprey does.
So pick the capability you want based upon what the aircraft does best and use it that way.
The design of the various rotor systems account of that.
Comparing Service Ceilings of a Helicopter to the Osprey is an Apples to Oranges comparison unless you limit the Osprey to operating in the "Helicopter Mode". Such discussions should make a balanced comparison and not one tilted towards one or the other of the designs.
One cannot expect a Helicopter to perform at altitude in the cruise as does the Osprey.
Likewise we will not ever see an Osprey land on Everest as a helicopter has done or set an altitude record like the Lama did.
I doubt we shall see a Helicopter cruise as fast as the Osprey does.
So pick the capability you want based upon what the aircraft does best and use it that way.
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The blades of a rigid rotor system are not any more highly stressed than the blades of a conventional rotor are, assuming both are made of similar materials. Either type of blade is designed to accommodate the load/lifecycle required from the blade given the properties of the materials used to construct it. A rigid rotor blade is obviously much stiffer in flap bending and torsion than a conventional rotor blade. Thus a rigid rotor blade experiences less bending and torsional deflection than a hinged blade does. But the relative stress/strain of each blade design would be similar.
The much stiffer rigid rotor blades also create far greater out-of-plane (cyclic) moments about the mast. But the trade-off is that the rigid rotor is much more responsive. The reason rigid rotors have not been more widely used is that it is incredibly difficult to design a rotor hub/mast system capable of handling the huge out-of-plane moments rigid rotor blades produce.
The much stiffer rigid rotor blades also create far greater out-of-plane (cyclic) moments about the mast. But the trade-off is that the rigid rotor is much more responsive. The reason rigid rotors have not been more widely used is that it is incredibly difficult to design a rotor hub/mast system capable of handling the huge out-of-plane moments rigid rotor blades produce.
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Singapore Airshow 2014: AFSOC explores gunship-variant Osprey, marines show interest
Gareth Jennings, Singapore - IHS Jane's Defence Weekly
12 February 2014
AFSOC is looking at giving its CV-22 tiltrotor aircraft a gunship capability, although no details have yet been released. Source: US Air Force
The US Air Force Special Operational Command (AFSOC) is to develop a gunship variant of the Bell-Boeing V-22 Osprey tiltrotor that also has the US Marine Corps (USMC) interested, a senior service official revealed on 13 February.
Speaking at the Singapore Airshow at the Changi Exhibition Centre, USMC Lieutenant Colonel Eric Ropella, PMA-275 Program Manager International Programs, said that AFSOC is looking at developing a prototype gunship-version of its CV-22 aircraft, and that the USMC is following developments with regard to its MV-22.
"[AFSOC] is looking at a number of different options [in terms of weaponry and configurations] for a gunship. The marines are always interested in every new capability [for the V-22]," he said.
While the concept is still in its early stages, Col Ropella hinted that the CV-22 may be fitted with forward-firing missiles, but beyond that he did not reveal any further details. However, when asked about the possibility of high-energy weapons, such as lasers, being fitted, he said: "All things are on the table. Some engineers at NAVAIR [Naval Air Systems Command] probably have dreams about [lasers] on the V-22."
Given the V-22's tiltrotor configuration and nearly 12 m diameter rotorblades, forward-firing munitions could not be carried on underwing hardpoints. Instead, the aircraft would either have to employ ramp-mounted or cargo bay-stored canister munitions, similar to those carried by the USMC's KC-130J Harvest HAWK Hercules gunship, or sponson-mounted stub-wings.
A side-firing cannon/machine gun could be fitted, but this would involve some structural re-modelling as the V-22 does not have a paratrooper door on the left-side aircraft fuselage, and the door on the right side is located forward of the rotors, which would present safety issues for the aircraft.
The gunship is one of a number of special mission variant V-22s being considered, Col Ropella noted, with aerial refuelling (already demonstrated), command and control, surveillance, and executive transport roles also being explored. "There are a seemingly endless number of applications that exist [for the V-22]," he said.
With regard to the MV-22's current role, Col Ropella said that crisis response "is quickly becoming its bread and butter mission".
In May 2013, the USMC stood up a detachment of six MV-22s and two Lockheed Martin KC-130J aerial refuelling aircraft in southern Spain to respond to emergency contingencies within the US Africa Command (AFRICOM) area of responsibility. In addition to the aircraft, 500 marines and other personnel are on standby at Morón Air Base under the auspices of the Special-Purpose Marine Air-Ground Task Force, Crisis Response (SP-MAGTF CR).
The SP-MAGTF CR has been created as a result of lessons learned following the death of the US Ambassador to Libya and three other staff members after militiamen overran the consulate in Benghazi. With unrest and instability continuing across North Africa, Col Ropella said that the duration of the mission has yet to be decided, although he noted that Morón will not be a permanent basing location for the USMC.
Gareth Jennings, Singapore - IHS Jane's Defence Weekly
12 February 2014
AFSOC is looking at giving its CV-22 tiltrotor aircraft a gunship capability, although no details have yet been released. Source: US Air Force
The US Air Force Special Operational Command (AFSOC) is to develop a gunship variant of the Bell-Boeing V-22 Osprey tiltrotor that also has the US Marine Corps (USMC) interested, a senior service official revealed on 13 February.
Speaking at the Singapore Airshow at the Changi Exhibition Centre, USMC Lieutenant Colonel Eric Ropella, PMA-275 Program Manager International Programs, said that AFSOC is looking at developing a prototype gunship-version of its CV-22 aircraft, and that the USMC is following developments with regard to its MV-22.
"[AFSOC] is looking at a number of different options [in terms of weaponry and configurations] for a gunship. The marines are always interested in every new capability [for the V-22]," he said.
While the concept is still in its early stages, Col Ropella hinted that the CV-22 may be fitted with forward-firing missiles, but beyond that he did not reveal any further details. However, when asked about the possibility of high-energy weapons, such as lasers, being fitted, he said: "All things are on the table. Some engineers at NAVAIR [Naval Air Systems Command] probably have dreams about [lasers] on the V-22."
Given the V-22's tiltrotor configuration and nearly 12 m diameter rotorblades, forward-firing munitions could not be carried on underwing hardpoints. Instead, the aircraft would either have to employ ramp-mounted or cargo bay-stored canister munitions, similar to those carried by the USMC's KC-130J Harvest HAWK Hercules gunship, or sponson-mounted stub-wings.
A side-firing cannon/machine gun could be fitted, but this would involve some structural re-modelling as the V-22 does not have a paratrooper door on the left-side aircraft fuselage, and the door on the right side is located forward of the rotors, which would present safety issues for the aircraft.
The gunship is one of a number of special mission variant V-22s being considered, Col Ropella noted, with aerial refuelling (already demonstrated), command and control, surveillance, and executive transport roles also being explored. "There are a seemingly endless number of applications that exist [for the V-22]," he said.
With regard to the MV-22's current role, Col Ropella said that crisis response "is quickly becoming its bread and butter mission".
In May 2013, the USMC stood up a detachment of six MV-22s and two Lockheed Martin KC-130J aerial refuelling aircraft in southern Spain to respond to emergency contingencies within the US Africa Command (AFRICOM) area of responsibility. In addition to the aircraft, 500 marines and other personnel are on standby at Morón Air Base under the auspices of the Special-Purpose Marine Air-Ground Task Force, Crisis Response (SP-MAGTF CR).
The SP-MAGTF CR has been created as a result of lessons learned following the death of the US Ambassador to Libya and three other staff members after militiamen overran the consulate in Benghazi. With unrest and instability continuing across North Africa, Col Ropella said that the duration of the mission has yet to be decided, although he noted that Morón will not be a permanent basing location for the USMC.
There is no doubt that the military would like a gunship version of the V-22. The U.S. Air Force has probably been experimenting with such a thing for a while but just hasn't admitted it until now.
We knew that the June, 2012 "Eglin" accident was caused by low-level formation work. We now know that the Air Force has admitted that the CV-22s were practicing low-level formation gunnery at 80 knots and 350 feet agl. What the Air Force admits is that they were using the ramp-mounted machine gun and firing...backward at targets?? Uhhh, ooooookay... (See the undated article linked below from the breakingdefense.com website.) What they admit to the public may or may not be the entire truth.
I suspect that since it was Eglin, and we know that all sorts of experimental "stuff" goes on at Eglin, they probably had some "other" gun configuration that they were testing but did not and do not want to admit. But it would be logical.
It'd be nice if they could come up with a gunship version of the V-22, and we fully understand the military's urgency to do so. I mean, let's face it - we very nearly lost those three ships that were sent on that rescue mission to Bor, South Sudan back in December. If there'd been just three teenagers with RPG's who actually knew how to use them, we might be telling a different story about that mission today.
AFSOC Crash Report Faults Understanding Of Osprey Rotor Wake « Breaking Defense - Defense industry news, analysis and commentary
We knew that the June, 2012 "Eglin" accident was caused by low-level formation work. We now know that the Air Force has admitted that the CV-22s were practicing low-level formation gunnery at 80 knots and 350 feet agl. What the Air Force admits is that they were using the ramp-mounted machine gun and firing...backward at targets?? Uhhh, ooooookay... (See the undated article linked below from the breakingdefense.com website.) What they admit to the public may or may not be the entire truth.
I suspect that since it was Eglin, and we know that all sorts of experimental "stuff" goes on at Eglin, they probably had some "other" gun configuration that they were testing but did not and do not want to admit. But it would be logical.
It'd be nice if they could come up with a gunship version of the V-22, and we fully understand the military's urgency to do so. I mean, let's face it - we very nearly lost those three ships that were sent on that rescue mission to Bor, South Sudan back in December. If there'd been just three teenagers with RPG's who actually knew how to use them, we might be telling a different story about that mission today.
AFSOC Crash Report Faults Understanding Of Osprey Rotor Wake « Breaking Defense - Defense industry news, analysis and commentary
FH, the thorny problem for the arming of the V-22 is one of geometry, and where stuff already is in the body of the aircraft.
Where do you put the weapons, where is your firing arc, and where are your firing stops? The answer to those is based on the various parts of the engine and wing and rotorprops that you don't want to hit.
A forward firing rig looks dubious, from what I have sorted out, but there may be room for a sort of sidewards firing arms station, see various sidewards firing armaments on the AC-130 for a rough idea on what the art of the possible might include.
Where do you put the weapons, where is your firing arc, and where are your firing stops? The answer to those is based on the various parts of the engine and wing and rotorprops that you don't want to hit.
A forward firing rig looks dubious, from what I have sorted out, but there may be room for a sort of sidewards firing arms station, see various sidewards firing armaments on the AC-130 for a rough idea on what the art of the possible might include.
