Fairey Rotodyne

[Jeffry Fontaine]

For those of you that have the Rotodyne in protective custody.  Have you considered adding the C-130J engines and propellers to the Airfix kit?  Other parts from the C-130 could also be useful in making the insides look a bit better.  You could also kit bash it with the old Italeri AC-130A/E or the Esci/AMT-Ertl AC-130H and AC-130U for any gunship ideas. 

If you are really looking for something to do with your Rotodyne kit.  Why not kit bash it with a 1/144th scale C-130 Hercules to create the Hercules Rotodyne proposal?

[Joe C-P]

I only have two of them, and they're dedicated to the COD and the USMC assault craft. The COD is about halfway done, and I have acquired an AH-1 to supply the chin turret and other weapons for the latter.

I should it dig them out again. If I can finish one more model I can buy another.  I promised my wife I'd cut down on the unbuilts by only buying one for each three I finish.

JoeP

[PR19_Kit]

I'm bumping this as I've just found THE book on the 'dyne!

It's absolutely stuffed with photos, diagrams and other really interesting stuff about that well underated aircraft (apart from its noise...) The book is called 'Fairey Rotodyne' (catchy title, eh?) by David Gibbings, an ex-FAA helicopter pilot and noted author on all things rotary winged. Price £12.99 (mine was more expensive ) and it's on Amazon at

http://www.amazon.co.uk/Fairey-Rotod...3108288&sr=8-1

There are lots of details about the proposed production aircraft, the Type 'Z', amongst which it shows the beaver tail for the military version, which is exactly how I was going to build my planned Rotodyne HC3! It also has tapered outer wings, not something I've seen before and FOUR fins. The two outer ones are in one piece and pivot at the tailplane level so that the upper tips swing out and the lower tips swing in, and at the same time the two smaller fins on the top of the tailplane fold sideways.

The subject of how the fins on the prototype hinged has come up numerous times, and the book clarifies this quite well. Originally the 'dyne' only had the lower fixed halves, but the upper parts were added early on in the flight test programme. They were fixed and slanted outboard at 60 deg to the horizontal to start with, as in the Airfix and Revell kits, but the dihedral effect of this was too strong, so they were made to hinge. When on the ground they were horizontal and hinged to the vertical when the rotor was up to its 140 rpm lift-off speed. It's not mentioned in the book, but some photos on the ground show them just slightly above the horizontal, and these all seem to have been taken late in the programme.

The third centre fin was also added later on on the programme, and in all the photos that show it in the book it's vertical. But it must have folded flat along the tailplane as in the photos of the 'dynes flight into the Battersea heliport you can't see it when the aircraft was on the ground, yet it's clearly there when it's taking off or on the approach. What seems to be certain is the centre fin didn't slant to port or starboard, as the Revell kit is modelled. That was just an interim position in mid-fold as far as I can see.

There's also an explanation of why the 'dyne was so loud when I saw it while it flew from RAF Benson. The Benson flights were part of the single engine descent tests, and the aircraft had a very clever air distribution system which ensured that any two opposing tip jets recieved combustion air if one of the main engines failed. The Benson tests were to prove this idea worked, thus the numerous take-offs and landings, and the high noise levels as the one remaining single engine was running at max. power a lot of the time.

All fascinating stuff.

The reason for the 'dynes demise is also covered at some length, and it seems the noise issue was NOT the prime reason as that issue had been solved by early 1962. Also it's often stated that the merger between Westland and Fairey meant that Westland had no interest in the 'dyne programme, but it seems the opposite is the case. Westland cancelled their own Westminster heavy-lift chopper programme in favour of working on the 'dyne, and over half of the 'dyne's development programme took place under Westland's ownership.

The villain of the piece seems to have been Rolls-Royce, who took over the ailing Napier company around the same time as the Westland/Fairey merger. While R-R were embroiled in their Government planned merger with Bristol Engines, they had no time to develop the specific Tyne for the production 'dynes, nor the RB176 gas generators to drive the rotor (production 'dynes were to have FOUR engines, but the RB176s were mounted aft of the Tynes and had separate wing-top intakes and side exhausts) This meant that Westland couldn't guarantee the promised production dates for Okanagan, Japan Airlines, New York Helicopters or BEA and so the whole programme folded as the Government wouldn't fund the extended development period.

Yet ANOTHER TSR2 type debacle! 

[Mossie]

I must get that book.  To me, the Rotodyne is one of the greatest British procurement $%"£ up's & beats the TSR.2 for potential.  It had the potential to revoloutionise helicopters, short haul airliners & transport aircraft.  The reasons behind it's demise are usually described pretty simplistically, but in the end it was a mix of techincal, political & the launch customer (BEA) shifting the goalposts.

I did some profiles a while back of the definative Z model, military in the first few pages, civil later.  They're some of my earliest & not that great, but give you an idea of how they might have looked:
http://www.whatifmodelers.com/index.php/topic,12245.0.html

I've mentioned it elsewhere, but I'm very much considering taking the Tyne engines from a Heller C-160 & scabbing them onto the Airfix Rotodyne as a halfway house between the Y (prototype) & Z versions.  In hindsight, this may have been the best way to get the Rotodyne into production, produce a smaller, more limited version based on the prototype & then develop a more capable version in the form of the Z.

[PR19_Kit]

I've mentioned it elsewhere, but I'm very much considering taking the Tyne engines from a Heller C-160 & scabbing them onto the Airfix Rotodyne as a halfway house between the Y (prototype) & Z versions.  In hindsight, this may have been the best way to get the Rotodyne into production, produce a smaller, more limited version based on the prototype & then develop a more capable version in the form of the Z.

Mossie,

That's exactly what I was planning for my HC3! But now I'll go further down the Type Z line and taper the wings as well etc.

I doubt just doing the engine change would have helped, reading at what the book says. R-R would still have been their usual obstructive selves and delayed things.

[Mossie]

Doesn't suprise me that Rolls Royce were complicit.  Reading into many projects it seems that they played some very dirty games & more than one project was at least helped on it's way due to RR medling.  I remember seeing an inteview with Frank Whittle & he had a grudging respect for Baron Hives, who came straight & out & told him that he was going to have the jet engine from him!

[GTX]

Speaking of the Rotodyne, has anyone else seen this?

Regards,

Greg

[dy031101]

I would assume the rotors can be made to fold?

RP1's Rotodyne-capable Daring class destroyer illustration get me keeping thinking a Rotodyne as a ship-borne ASW or even AEW machine.

[jcf]

I would assume the rotors can be made to fold?

It would require some redesign as the rotor blades include the pressurized air ducting and fuel pipes for
the tip burners.

[Mossie]

Greg, that's the book Kit mentioned in the above post & I've just taken delivery of it today.  It's fantastic, worth getting hold of for anyone who's interested in or wants to build a model of the Rotodyne.  There's quite a lot of detail photos including internal ones.  There's also some great pics of the Rotodyne Z mock up, which I never realised existed until I got this book.  There's a final chapter titled 'Renaissance' which covers plans to resurrect the technology by Groen Brothers & Carter Aviation Technologies.  An appendix re-prints a Flight article by the pilot, Ron Gellatly, on his views on the program.  Everything you'd want!

I would assume the rotors can be made to fold?

It would require some redesign as the rotor blades include the pressurized air ducting and fuel pipes for
the tip burners.

There's a diagram showing this in the book.  The port & starboard blades were to fold to line up with the fore & aft blades.  An electrical deicing system would also have been incorporated.  It doesn't mention how the rotor would be revised to incorporate these changes, although the diagram shows a very similar rotor.  Either the diagram was just for 'look-see' purposes, or the changes would be minimal.

[PR19_Kit]

Having read the book 3-4 times now, I'm surprised they needed electical de-icing.

The air feed for the tip jets ran right along the leading edge and the air was above 100 deg F so why not just use that heat? I suppose we'll never know now as all the technical docs were destroyed by some 1960s JMN.

[Hobbes]

Maybe they wanted the option to deice the rotor without running the tipjets? Having the rotor spinning and sending chunks of ice everywhere wouldn't be pleasant.

[Ed S]

Maybe they wanted the option to deice the rotor without running the tipjets? Having the rotor spinning and sending chunks of ice everywhere wouldn't be pleasant.

Most definitely not.  I can attest to this from personal experience.  Back in '76, shortly after the USAF has sent OV-10 Broncos to Germany, we were deploying our squadron from Germany to Spain.  It was winter and the weather was typical for that time of year.  We were flying at about 20-25,000 ft and were experiencing some light icing.  A number of the a/c in the formation were hearing loud bangs and having the back windows broken.  The back window on the OV-10 is in direct line with the props.  It turned out that the props were icing and slinging the ice onto the side of the fuselage and occasionally through the window.  Once we got on the ground, we found that 9 of the 12 planes had broken windows.  This was the first time anyone had actually flow the OV-10 in any kind of real icing.  Most of the previous experience with the plane was in the southern US or in SEA.  Needless to say, shortly after this, some serious restrictions on flying in icing conditions were added to the flight manual.

Ed

[PR19_Kit]

Maybe they wanted the option to deice the rotor without running the tipjets? Having the rotor spinning and sending chunks of ice everywhere wouldn't be pleasant.

That could be it, yes. They started the rotor turning with just 'cold' air (at 100 deg F...!) and only started the jets after it had reached 120 rpm. Chunks of ice coming off at that speed and at 15-20 ft above the ground, would make a right mess of the heliport terminal windows! I can't find if the 'dyne had a rotor brake or not, but I imagine that it must have at that period of chopper history.

[Weaver]

Modelzone have the Revell 1/78th Rotodyne in now, but at £17, I'm afraid I won't be getting one.