The right aircraft wins…again

[johnpauljones1776]

What did you fix, exactly? You're still making the same claim without evidence or rationale that you did before.

Aight I’ll be specific, I see benefits in both the V22 rotating Nacelle and the V280’s splitting nacelle. V22 has all systems encased but, and I’m making an assumption here, it seems as though there’s single point failure with the entire nacelle rotating. Idk the system at all but hard overs and jams are very much a thing and that’s why most control surfaces have more than one hydraulic actuator. For the V-280, it looks like it has a redundant four bar mechanism to translate the rotors to point vertical and there appears to be some redundancy. The trade off here is all the systems in that now split nacelle are exposed when the rotors have any vertical component making it susceptible to birdstrikes. I bet an 8 lb bird, what part 25 certifies to (14 CFR 25.631) would cause a catastrophic event. I’m just going off what I know, I understand this doesn’t fall under prt 25 whatsoever.

Fyi Catastrophic events are entire loss of aircraft events. Airframe manufacturers need to show reliability to the 10^-9 or in other words, that event might happen once in a billion hours of that airframe operating across the entire fleet. Ie bird strikes can not cause catastrophic failures cuz they are random in nature and you can’t plan where they will hit

I think it’s a super cool aircraft. Got to talk to a test pilot that flew it. He said it’s a big improvement over the Osprey from a human factors perspective, completely seamless in the transition from forward to vertical flight and vice versus.

 

[sevenhelmet]

I think it’s a super cool aircraft. Got to talk to a test pilot that flew it. He said it’s a big improvement over the Osprey from a human factors perspective, completely seamless in the transition from forward to vertical flight and vice versus.

That’s good to hear. I got to fly the V22 simulator at Pax once, and found the transition from forward flight to vertical lift… awkward. I’m sure it’s easily compensated for with training, but I could see how that can be an area of vulnerability for the aircraft.

 

[wink]

That’s not an intake. The engine intake does have a particle separator.

This is only exposed at low speeds.

Any fairing would add complexity for purely cosmetic considerations.

This is like saying the swashplates and rotor heads of helicopters need to have a fairing and bleed air source. They’re just as exposed.

I mean, look at all these complex moving parts just exposed to the elements. Outrageous!

View attachment 37931

I know all that stuff. I'll note that that spinning rotor head is not what amounts to a flat surface at the end of an open box. That is what the V280 looks like below the tilted rotor. So, to use your references to helo rotor heads and their known vulnerabilities, maybe someone can explain to me how that compares to any threat to the V280 system when the rotor is tilted?

At the risk of spooling up the tilt rotor mafia again, I am wondering why in the V280 Bell changed to the current tilts system. The AW609 the V280 is based on tilted the entire nacelle like the Osprey. Off the top of my head I can think weight, but am curious.

I had no idea that people were so defensive about tilt rotors this late in the game. It isn't like the questions are not reasonable and I am not able to comprehend the answers. "Just because" does not do it. "I don't know" is absolutely fine. I don't know or would not be asking. I am not being critical of the V280, I don't have the information to be critical.

 

[wink]

Dude... tilt rotors have been flying for 70+ years. Considering that there are posters here with actual experience with these platforms, you may consider that shutting the fuck up may be one of your best options in this thread.

Really? Seventy years eh? Sure was a success. Lots of defined demonstrated tilt rotor technology along the way? How many designs succeeded before the Osprey?

If you hadn't noticed, I asked the question of the experts. I know who they are. That is why I am here. But I am not getting any real answers, just deflections. I mean, if they don't know fine. But that is not what I am hearing. I have not made a single statement rejecting the knowledge and experience of the rotorcraft experts we have here. No reason to shut the fuck up unless reasonable questions are offensive.

 

[phrogdriver]

Looking at the rotorhead made me think that Bell has never commercially produced a fully articulated helicopter. Can anybody think of one?

412.

I know all that stuff. I'll note that that spinning rotor head is not what amounts to a flat surface at the end of an open box. That is what the V280 looks like below the tilted rotor. So, to use your references to helo rotor heads and their known vulnerabilities, maybe someone can explain to me how that compares to any threat to the V280 system when the rotor is tilted?

At the risk of spooling up the tilt rotor mafia again, I am wondering why in the V280 Bell changed to the current tilts system. The AW609 the V280 is based on tilted the entire nacelle like the Osprey. Off the top of my head I can think weight, but am curious.

I had no idea that people were so defensive about tilt rotors this late in the game. It isn't like the questions are not reasonable and I am not able to comprehend the answers. "Just because" does not do it. "I don't know" is absolutely fine. I don't know or would not be asking. I am not being critical of the V280, I don't have the information to be critical.

At the risk of spooling up the tilt rotor mafia again, I am wondering why in the V280 Bell changed to the current tilts system. The AW609 the V280 is based on tilted the entire nacelle like the Osprey. Off the top of my head I can think weight, but am curious.

I had no idea that people were so defensive about tilt rotors this late in the game. It isn't like the questions are not reasonable and I am not able to comprehend the answers. "Just because" does not do it. "I don't know" is absolutely fine. I don't know or would not be asking. I am not being critical of the V280, I don't have the information to be critical.

To keep coming back to the gap without something more specific is just getting ridiculous. Do you really think that after 10 years and over a billion dollars, the engineers are slapping their foreheads and saying “You mean it needs to fly OUTDOORS?!?”

The pylon conversion actuator and the front of the gearbox are there. I’m failing to see the chain of failures you’re proposing, especially when you’re claiming catastrophic results.

There are costs and risks to adding safety measures when none are needed. Add a fairing to protect…nothing…and you’ve added a point of failure. What if THAT mechanism gets stuck and jams the nacelle, for example?

To another question, fixing the engine is a VAST improvement in reliability and maintainability. First, turbine engines don’t like hanging vertically—it causes oil leaks at the seals. Second, it eliminates having to make electrical, hyd, and oil lines bend or swivel hundreds of times a flight. Third, it improves vibratory characteristics. Fourth, it makes engine replacement far simpler. Fifth, you stop having the proprotor pump sand and dirt directly into the intake.

 

[Randy Daytona]

412.

I was thinking of a traditional rotor system for big helicopters with vertical and horizontal hinge pins.

 

[wink]

To keep coming back to the gap without something more specific is just getting ridiculous. Do you really think that after 10 years and over a billion dollars, the engineers are slapping their foreheads and saying “You mean it needs to fly OUTDOORS?!?”

The nature of my question was exactly WHAT have the engineers determined to be a threat in that area, and how have they dealt with it. Operating restrictions or some kind of system. I did not suggest that an icing threat would be a surprise to Bell. I keep coming back to it becasue some people are mischaracterizing what I am posting and no one has answered my question. Just say we don't know.

There are costs and risks to adding safety measures when none are needed. Add a fairing to protect…nothing…and you’ve added a point of failure. What if THAT mechanism gets stuck and jams the nacelle, for example?

Ah...no shit. Just makes me more curious. If there is an FOD or icing threat, and the analysis is that mechanical systems are too costly, complex or pose a failure point, then maybe there will be certain flight restrictions. Not like that isn't common in helos. Again, that is all I am asking.

To another question, fixing the engine is a VAST improvement in reliability and maintainability. First, turbine engines don’t like hanging vertically—it causes oil leaks at the seals. Second, it eliminates having to make electrical, hyd, and oil lines bend or swivel hundreds of times a flight. Third, it improves vibratory characteristics. Fourth, it makes engine replacement far simpler. Fifth, you stop having the proprotor pump sand and dirt directly into the intake.

Thank you!! I assumed much, but it means more coming from you given your experience and access.

 

[phrogdriver]

The nature of my question was exactly WHAT have the engineers determined to be a threat in that area, and how have they dealt with it. Operating restrictions or some kind of system. I did not suggest that an icing threat would be a surprise to Bell. I keep coming back to it becasue some people are mischaracterizing what I am posting and no one has answered my question. Just say we don't know.

Ah...no shit. Just makes me more curious. If there is an FOD or icing threat, and the analysis is that mechanical systems are too costly, complex or pose a failure point, then maybe there will be certain flight restrictions. Not like that isn't common in helos. Again, that is all I am asking.

Thank you!! I assumed much, but it means more coming from you given your experience and access.

The thing is, I said there’s nothing there a couple times, and we keep going around this barn. Then someone else pipes up saying someone will have to die for it to be fixed. For what to be fixed?

Not everything that moves needs to be deiced or have a protective fairing. That’s true of all aircraft—flaps, ailerons, elevators, landing gear, all sorts of stuff.

 

[wink]

Not everything that moves needs to be deiced or have a protective fairing. That’s true of all aircraft—flaps, ailerons, elevators, landing gear, all sorts of stuff.

All well and good, except the above. Partially true. You can solve the problem with flight restrictions if needed.

 

[phrogdriver]

All well and good, except the above. Partially true. You can solve the problem with flight restrictions if needed.

I think it’s entirely premature to say there’s a “problem” to be solved at all. What problem?

As mentioned previously, the Osprey’s PCA is completely exposed in VTOL mode and there are no flight restrictions related to it.

 

[IRfly]

At the risk of spooling up the tilt rotor mafia again, I am wondering why in the V280 Bell changed to the current tilts system. The AW609 the V280 is based on tilted the entire nacelle like the Osprey. Off the top of my head I can think weight, but am curious.

Disclaimer: not a tiltrotor expert.

I was told by a former boss who worked in the V-22 program office that the change was to allow greater field of view, particularly when landing. When the entire nacelle tilted, it would block not only the view, but also a gunner at certain angles.

 

[phrogdriver]

Disclaimer: not a tiltrotor expert.

I was told by a former boss who worked in the V-22 program office that the change was to allow greater field of view, particularly when landing. When the entire nacelle tilted, it would block not only the view, but also a gunner at certain angles.

The reliability and maintainability aspects are probably more important, but yes, the reason the V-22 never got guns on the side was because the nacelles block a LOT of view out the sides.

Especially with a side door aircraft, opening up the egress area has huge benefits for both troops and aircrew.

 

[IRfly]

Just saw the new unmanned V-247 at SAS.

Looks like a pretty amazing bird that can do a lot of missions…but it’s interesting because it’s single-engine (located in the main fuselage) and the wings/nacelles/rotors are simply a succession of gearboxes

 

[ChuckMK23]

Air Force Will Look at CV-22, New Army Helicopter for Long-Range Combat Search and Rescue | Air & Space Forces Magazine

The AIr Force will consider the new Army V-280 helicopter for long-range combat search and rescue but may rely on the CV-22 in the interim.

www.airandspaceforces.com

 

[insanebikerboy]

Air Force Will Look at CV-22, New Army Helicopter for Long-Range Combat Search and Rescue | Air & Space Forces Magazine

The AIr Force will consider the new Army V-280 helicopter for long-range combat search and rescue but may rely on the CV-22 in the interim.

www.airandspaceforces.com

Interesting way they titled the article. The CV-22 has already conducted real world, long range CSAR and infil/extract. Wonder what improvements the new Army version would bring that the CV-22 can’t currently do.