RAF Puma Helicopter rotors

[Selwyn]

Can RAF puma helicopter rotors be folded?

I have looked everywhere and can't seem to find a picture with the rotors folded anywhere.

Selwyn

[garryrussell]

Not seen one..but this quotes the width with blades folded?

http://www.lw.admin.ch/internet/luftwaffe/en/home/dokumentation/assets/helicopter/puma.html

Edited December 29, 2012 by garryrussell

[VulcanXH558]

Hi Selwyn,

although this is not an RAF machine the rotors are folded on this French Puma:

Chris

[Wez]

In the 12 years I worked on them I never saw it done. Don't ever recall seeing any ground equipment to support the blades when folded either.

About the only time I can think of that you'd need to do that for would be for air transportation, back when I worked on them we used to remove the tailboom, sliding cowling and Main Rotor Gearbox (complete with Main Rotor Head - saves having to rig it that way) for air transportation but I stopped working on them a loooong time ago, before we had C-17's, don't know if that changed anything.

Looking at the picture Chris posted whilst I was typing this confirms it is technically possible, it's another matter entirely whether the RAF did it or had the wherewithal to do it. BTW, in my time in the RAF we never operated Puma's from ships.

There's a few other ex Puma types here so they may know better.

Wez

Edited December 29, 2012 by Wez

[SkippyBing]

Looking at the picture Chris posted whilst I was typing this confirms it is technically possible, it's another matter entirely whether the RAF did it or had the wherewithal to do it.

Do the RAF's Pumas have a foldable rotorhead though? If you're not going to do it then it saves a lot of complexity and maintenance by having a non-folding option, for instance the Army's Lynx don't have a folding rotorhead and I don't think the RAF's Merlins do either.

[VulcanXH558]

Here's a photograph of an RAF Puma in the back of a C-17, with the rotors removed for transportation:

I've come across one or two other photographs of RAF Puma's in storage and being unloaded from ships with the rotors removed aswell:

Chris

Edited December 29, 2012 by VulcanXH558

[Wez]

Do the RAF's Pumas have a foldable rotorhead though? If you're not going to do it then it saves a lot of complexity and maintenance by having a non-folding option, for instance the Army's Lynx don't have a folding rotorhead and I don't think the RAF's Merlins do either.

It's only complex if you have a powered folding option like the Queenies do, with the Puma the blade is held on by two pins, all you'd have to do is rotate the rotor head to the appropriate position, knock out the forward pin and swing the blade back to the folded position - simples!

Of course the lack of complexity in the rotor head would have to be compensated for elsewhere, in this case manually with some form of supporting cradle and restraining ropes - you don't want a wildly swinging blade smashing into structure or for that matter flailing about and wrecking the rotor head, you've just lost any advantage to not having the maintenance burden of power folding!

It's interesting to see that neither the Puma being transported in the C-17 or on the ship have their blades folded, they have them removed which again points to my earlier comment that in my recollection the RAF never had the ground equipment to fold the blades.

Wez

[SkippyBing]

It's only complex if you have a powered folding option like the Queenies do, with the Puma the blade is held on by two pins, all you'd have to do is rotate the rotor head to the appropriate position, knock out the forward pin and swing the blade back to the folded position - simples!

After trying to remember how the blades folded on the Lynx, and then finding some pictures, I remember there was one position you could fold the head in, handily marked by beta lights, and some sort of nifty retaining clip on the bottom of each pair of pins called a spectacle clip which let you remove one pin without having to store the clip separately. So I appear to have remembered things as more complicated than they were! Obviously you still need the attachment points on the airframe for the blade support handles, as seen in the picture of the French one, which may be something else the RAF didn't have as it would just be dead weight on the airframe.

Interestingly when RN Lynx get moved by air they still take the blades off, I did ask as it seemed to introduce an unnecessary delay in getting it home from Brize on a December afternoon, I think there was concern that there could be a lot of chaffing of the blades as the vibration would be different to that on a ship.

Edited December 29, 2012 by SkippyBing

[Jabba]

In the 12 years I worked on them I never saw it done. Don't ever recall seeing any ground equipment to support the blades when folded either.

About the only time I can think of that you'd need to do that for would be for air transportation, back when I worked on them we used to remove the tailboom, sliding cowling and Main Rotor Gearbox (complete with Main Rotor Head - saves having to rig it that way) for air transportation but I stopped working on them a loooong time ago, before we had C-17's, don't know if that changed anything.

Looking at the picture Chris posted whilst I was typing this confirms it is technically possible, it's another matter entirely whether the RAF did it or had the wherewithal to do it. BTW, in my time in the RAF we never operated Puma's from ships.

There's a few other ex Puma types here so they may know better.

Wez

Like you said Wez, I have never seen a Puma with its blades folded, although in theory it could be done. When the second batch of Pumas were sent to the Gulf region in 1990 by ship they had their main rotors removed. I do recall that when I was on my Puma 'Q' course with Westlands, the instructor did say that in the original idea of this battlefield helicopter was that it would land the blades would be folded and then some motors would drive the wheels so that it could go into a hide. Common sense prevailed with this (even if it was French common sense) and the blade fold and motor driven wheels were dropped due to the weight penalty that would have occured.

Edited December 29, 2012 by Jabba

[TimB]

I think you might be able to - but you would almost certainly have to disconnect the pitch change links to get the blades to a reasonable angle. I can't see the PCLs on the French photo above, so they may have been disconnected on it. On balance, removing the blades is probably easier. For transport, they were often loaded into the cabin through the rear hatch. Incidentally, operating a Puma from a ship (as opposed to transporting it and flying it from the deck in good weather) is not smart. There is a terrifying video of the French sea trials showing lots of matelots trying to stop the aircraft falling over....

Regards

Tim

[heloman1]

I think removing the Lynx blades whilst in transit is more to do with vibration/stress than anything esle but it would make loading/unloading much easier. Back to the original question though, there is/was no need under normal service condition to fold the blades on Puma (and Army Lynx) the Crabs have very large hangers whereas the navy do not, so a need for folding blades.

The Crab Merlins are the same, no power folding mechanism and therefore a simple to maintain main rotorhead,

Sikorsky even with the Whirwinds had the facility for folding main rotorblades, this carried through to the Wessex and by the time the Sea King came along it was all power operated.

Colin

[Wez]

the Crabs have very large hangers whereas the navy do not, so a need for folding blades.

The Hangars at most stations regardless of whether they were RAF or Pugwash were the same size - they were mostly built to a common standard pattern (my wife's Grandad was Chief Surveyor for the Ministry of Works and responsible for the siting of the majority of the airfields built during the wartime expansion period). So this is not strictly the case.

Admittedly, once you go onto a ship then things are a little different there...

The Crab Merlins are the same, no power folding mechanism and therefore a simple to maintain main rotorhead,

Sikorsky even with the Whirwinds had the facility for folding main rotorblades, this carried through to the Wessex and by the time the Sea King came along it was all power operated.

Colin

The advantage of power fold is of course it can be done in all weathers and makes it easier and less dangerous (to both personnel and aircraft) to do whilst the ship is underway.

I think you might be able to - but you would almost certainly have to disconnect the pitch change links to get the blades to a reasonable angle. I can't see the PCLs on the French photo above, so they may have been disconnected on it. On balance, removing the blades is probably easier. For transport, they were often loaded into the cabin through the rear hatch. Incidentally, operating a Puma from a ship (as opposed to transporting it and flying it from the deck in good weather) is not smart. There is a terrifying video of the French sea trials showing lots of matelots trying to stop the aircraft falling over....

Regards

Tim

Good spot on the PCL's, I saved the photo and blew it up to 400%, the PCL's don't appear to be fitted. What a PITA that must've been just to take a bloody photo!

Somebody must've been trying to prove a point methinks!

Wez

Edited December 30, 2012 by Wez

[JagRigger]

It's only complex if you have a powered folding option like the Queenies do, with the Puma the blade is held on by two pins, all you'd have to do is rotate the rotor head to the appropriate position, knock out the forward pin and swing the blade back to the folded position - simples!

Wez

Yes, but if you have messed with the head you are talking rebuild, indies, track / balance and airtest. You may as well have removed the blades completely

[Jabba]

Yes, but if you have messed with the head you are talking rebuild, indies, track / balance and airtest. You may as well have removed the blades completely

Not quite. Yes there will be the rebuild and indies, but if the same blade and associated parts go back into the same places that they came from there is no need for the track/ balance and air-test.

[Pete in Lincs]

Way Back When... Falklands war going on....

Some of us worked long hours fitting folding heads to a few Puma's at Odiham.

There was a 'civvy' team in the hangar too making vinyl covers (with zips) to cover the whole aircraft.

The idea was to send some down to the islands.

It was found however that the Puma isn't really suited to ship operation.

The u/c is fairly soft so during startup as the blades turn slowly at first it gets a bit wobbly until the rotor stabilises.

Can't remember how many heads we changed, but they would have been 33 sqn machines.

Not sure if they would have gone on the Atlantic Conveyor.

But, in the event it never happened.

Pete

[Wez]

Way Back When... Falklands war going on....

Some of us worked long hours fitting folding heads to a few Puma's at Odiham.

So Pete,

Is the folding MRH a different head to the standard Puma MRH? If it is I ain't never seen those, no siree!

In which case, the answer to the OP's question is a firm NO!

Wez

[Jabba]

It was found however that the Puma isn't really suited to ship operation.

The u/c is fairly soft so during startup as the blades turn slowly at first it gets a bit wobbly until the rotor stabilises.

I know what you mean about the U/C as it does wobble around a bit and looks like it might fall over at any minute. It then seems strange that the french have operated their Pumas of carriers, sending some of the ones that operated in the Gulf down on the Clemenceau, carrying out a few exercises on the way.

[Pete in Lincs]

From (ancient) memory,

There was an easy to disconnect mechanism on the top of the pitch change rods.

I think I remember a knurled knob to be undone, nappy pins & overcentre levers.

Not too much difference to the standard head at first glance.

Pete

[Wez]

From (ancient) memory,

There was an easy to disconnect mechanism on the top of the pitch change rods.

I think I remember a knurled knob to be undone, nappy pins & overcentre levers.

Not too much difference to the standard head at first glance.

Pete

Thanks Pete, certainly don't recall ever seeing anything other than the standard head even if the differences were minor, didn't even know a proper folding head for the Puma existed - you live and learn.

Wez

[sammy da fish]

Hello all, having now seen the above Quotes. To finally answer all of your speculation. The Puma is fitted with a folding head, BUT ther are only a few of us around that have folded the Blades. The kit to fold the blades was still around a cuple of years ago, but again nobody apart from myself and perhaps one or two other chaps have carried out such a task. For the Puma, it is easier just to remove two/four blades. All four blades can be removed in about ten minutes, where as fitment takes around twenty minutes with paperwork/ indes a few minutes more. Please chaps no more on this, this is the final answer.

Puma engineer 1978-2009 with 230Sqn/240 OCU/33Sqn