Fairey Rotodyne

[tigercat]

I've just been Stuart Slade's alternative History series and in these Rotodynes are dominant and have taken over all the traditional roles of helicopters.

[Mossie]

Tigercat reminded me, I was going to put all my thoughts on roles for the Rotodyne into one post as it's something we keep coming back too.

Civilian

Feederliner/Commuter This was the primary role that the Rotodyne was designed for.  It was expected to use heliports at a time when there were few city airports.  It would have been able to compete with both helicopters & fixed wing commuters such as the Fokker Friendship & HS 748 due to it's performance & VTOL capability.

Freighter The Rotodyne Z could be fitted with a loading ramp as an option, it would have been in the realm of the Bristol Superfreighter regards weight & capacity.

Flying Crane  The Rotodyne was demonstrated as being able to place a girder bridge accurately into place, it could have performed this role well.

Waterbomber   Quite possible, the speed & VTOL capability meant it would have been able to have the ability to load from bodies of water yet transiting quicker than a helicopter, putting it in the realm of the Canadair 215/415.

SAR It was quite a large aircraft & would find it difficult to fit into the roles of smaller helicopters traditionally used for civilian SAR.  It had a 109ft/33m rotor & the noise of the tip jets might have been an issue in this role.  It's speed & economy over helicopters may have made it more attractive however.

Car Ferry This role was starting to dwindle by the late sixties, but the Z's cabin was large enough to hold several cars (the Y demonstrated this, even if room was a little tight in the prototype), putting in competition with the Superfreighter again.

Police/Gendarmerie/Customs  Too large as a general 'eye in the sky' but could have been used for transport of large numbers of personnel in those few forces that use larger helicopters or fixed wing aircraft for this role such as the Bundesgrenzschutz.

Military roles next, feel free to discuss or chuck anything in I've missed.

[Mossie]

Military

Transport  Another major role for the Rotodyne.  The military Z would have had a loading ramp as standard with collapsible seating for a large number of troops (seventy IIRC?).  It could easily carry jeep size vehicles internally, a Bedford RL 3 ton lorry could be carried if the cab top was removed.  Roles related to this such as medevac, VIP transport & such were also likely.

Carrier Ops  Unlikely.  The Rotodyne Y was big, chinook size.  The Z was larger & wing on the Z would have been a problem & the 109ft rotor larger than any carrier capable helicopter.  It's possible it could land & supply super carriers if in range in range of the shore.

Gunship  Possible.  The most likely operator of a gunship would have been the US Army or Air Force.  Kaman (not Kamov! ) was selected as a licence manufacturer & could have converted airframes to act in this role, either in a guns-a-go-go ACH-47 or AC-47 Spooky style.  The low speed gyroplane charateristics might enable you to concentrate your fire.

SAR  CSAR is the most likely role for such a large platform, only a handful of forces operate large helicopters in the role.  Similar arguments apply as to civvy SAR, the tip jets & rotor wash could be a problem.

AEW/AWACS/ELINT  Possible.  Smaller platforms have been used for these roles.  Getting your radome/greeblies on board might need some creative engineering.

ASW  Land based ops are possible, but the problems outlined above for carrier ops apply.  The slow speed charactersitics in gyroplane mode might lend itself to this role as well as the VTOL capabilities.

Maritime Recce/Fisheries Protection  Possible.  Again, small platforms have been used in this role & the large speed range would be useful.

As before, pipe up if I've missed something or you've got your own views.

[Stargazer]

All of this makes it sound like the Rotodyne would have been sort of a jack-of-all-trades... and probably a master-of-none... 

[Rheged]

 I have a vague memory of reading somewhere, somewhen, that the Blue Water missile (demounted) , Bedford carrier  vehicle and  control landrover were modified to fit in the Rotodyne Z as a single self contained launch unit.    Is there anything more to this than my memory playing tricks?

[Mossie]

All of this makes it sound like the Rotodyne would have been sort of a jack-of-all-trades... and probably a master-of-none...  

Maybe!

I have a vague memory of reading somewhere, somewhen, that the Blue Water missile (demounted) , Bedford carrier  vehicle and  control landrover were modified to fit in the Rotodyne Z as a single self contained launch unit.    Is there anything more to this than my memory playing tricks?

I've seen in BSP Hypersonics a drawing of a SAM system (can't remember which without thumbing through it) within the Rotodyne, but not Blue Water.  IIRC Blue Water could have been slung under a helicopter?  I'll have a look later.

[dy031101]

Carrier Ops  Unlikely.  The Rotodyne Y was big, chinook size.  The Z was larger & wing on the Z would have been a problem & the 109ft rotor larger than any carrier capable helicopter.  It's possible it could land & supply super carriers if in range of the shore.

AEW/AWACS/ELINT  Possible.  Smaller platforms have been used for these roles.  Getting your radome/greeblies on board might need some creative engineering.

ASW  Land based ops are possible, but the problems outlined above for carrier ops apply.  The slow speed charactersitics in gyroplane mode might lend itself to this role as well as the VTOL capabilities.

Regarding ship-borne ASW, one can perhaps take inspiration from the Canadian Tribal a.k.a. Iroquois class destroyers for the carrier ship- appropriately-big deck and hanger except it might serve a single Rotodyne Y (JoeP mentioned a study for folding rotors, and the outboard wing could likely be made to fold, too...... what's the finspan of the Rotodyne?).

As for carrier-borne AEW...... would a CVA-01-class vessel be too small for the carrier?  

[tigercat]

I suppose Smaller compound gyroplanes. Is that the correct term? ,   could be developed for shipboard use

[Mossie]

As for carrier-borne AEW...... would a CVA-01-class vessel be too small for the carrier?  

Here you go, I've scaled Rotodyne Z's to CVA-01.  Scaling is as accurate as I can make it.  I've got one Rotodyne with the rotor disc highlighted & one on each of the deck lifts with the rotors folded in the manner proposed.  The Z is very snug in the length, the rest just doesn't fit. You could land it & store it on the deck, but getting it below isn't going to happen.

You might be able to get it on the lifts with some serious naval mods, wing & tail folding, different method of the rotor.  Even then you'd probably only be able to use the edge lift.  Then you've got to store it below decks.

If there was enough interest a naval version might have been done, or like tigercat says, a smaller version produced.  If the Rotodyne had been produced and then been all it was cracked up to be, Fairey/Westland might have developed other versions & I'm sure other manufacturers would have jumped on the bandwagon.

[Joe C-P]

My Rotodynes will be an RN COD bird, so it won't need to be sent below decks, and a USMC troop transport and gunship, which will need folding wings and rotor. I'm still not certain about one fitting onto an elevator on a LHA or LHD, though being deck edge it would be easier.

[dy031101]

Here you go, I've scaled Rotodyne Z's to CVA-01.

If a carrier-borne type is to be made, I'd think that it'd at least be based on the prototype Type Y if not like you said a smaller development.

Still, I'd agree that the carrier needs bigger evelators.

[rickshaw]

The naval mods needed - wing and nose/tail folds are not impossible and well within engineering possibility.  I'd suggest that you could use the deck edge lift more easily than the forward, centre lift.

I find the size of the lifts interesting.  Lifts have always been a limiting factor on British carriers, since the very first one was installed.  The USN just tends to design REALLY, REALLY, BIG ONES as a matter of course but the RN appears to go for the smallest needed for the current generation of aircraft, rather than thinking ahead.

[raafif]

I prefer civil choppers -- don't know why a Rotodyne Firebomber didn't suggest itself to me !?

[Hobbes]

That picture suggests a drawback of the Rotodyne design for firefighting: the propeller tips would get awfully close to the water.

[PR19_Kit]

How about folding the wing and engines a la V-22?

You'd need to move the landing gear into fuselage pods, also like the V-22, but that'd not be too difficult. Then a deck edge lift would work if the 'dyne was parked on it with the nose or tail outboard.

Erm, just thought of a problem there, one engine would conflict with the tail end of the fuselage, but I'll work on it......