What if WWII autogiro troopers?

Magniac · May 13, 2009

I've just been reading about the two leading developers of autogiro technology in the '20s and '30s, Juan de la Cierva of Spain and Harold Pitcairn of the US. I'd already known about the impressive short take-off and vertical landing abilities of the aircraft they had built separately of each other, but didn't know they had got their machines to actual VTOL by the middle of the nineteen thirties.

Here's a modern autogiro pilot demonstrating a 'jump' take off. A Youtube commenter explains what is happening in this video: "The main rotor is held in a neutral pitch position and is spinning at very high rpm (more than needed for flight) by an electric pre-rotator before take-off. When the pilot disconnects the pre-rotator, the pitch or the blades changes to a high angle of attack and lift is generated [by the main powerplant/secondary rotor]." This is the same principle as that used by the early designers to achieve vertical take offs.

My thought is this: if VTOL could be achieved with technology that existed by the middle of the thirties, why didn't the miltaries of the great powers adopt autogiros to any large extent before or during WWII? Surely someone must have seen how useful they would be as communications aircraft. Okay, they couldn't hover, but apart from that they could perform at least as many of the same roles that helicopters would in Korea and the Malayan Emergency/Suez Crisis. In fact autogiros powered by the radial engines of the era could easily have been more powerful than the helicopters in service between '44 and the introduction of the turbine-engined helos of the late fifties.

Or to put it another way, if you were a WWII airborne soldier would you rather make a soft, vertical landing on a battlefield in an autogiro the size of a de Havilland Beaver, or in a Waco glider? (Though technically both aircraft make unpowered landings, the autogiro is more controllable than the glider.)

It seems odd that so much time and energy was expended on helicopter R&D during the late thirties and the Second World War, when autogiros could have been adopted so much quicker than the few helos that were eventually put into service before the end of the war.

tallwingedgoat · May 13, 2009

I think bigger autogyros could've been built but they couldn't replace gliders since the latter had the ability to lift jeeps and artillery. If you wanted to move troops cheaply, you would drop them by parachute.

Autogyros could be useful as artillery spotters, medevacs, special forces transports, U-boot spotters for convoys, etc. Not sure how safe the technology would be during WWII though.

Landshark · May 13, 2009

tallwingedgoat said:
I think bigger autogyros could've been built but they couldn't replace gliders since the latter had the ability to lift jeeps and artillery. If you wanted to move troops cheaply, you would drop them by parachute.

It's not about moving them cheaply, it's about moving them effectively. Gliders were used because they negated the scattering problem you had with paratroops. A more developed autogyro could have doen the same thing but wouldn't have been dependent on towing aircraft and wind currents like a glider.

tallwingedgoat · May 13, 2009

Landshark said:
It's not about moving them cheaply, it's about moving them effectively. Gliders were used because they negated the scattering problem you had with paratroops. A more developed autogyro could have doen the same thing but wouldn't have been dependent on towing aircraft and wind currents like a glider.

Still if you had to move a 12,000 man division and an autogyro can move maybe 6 guys at a time, economics does come to play.

Even today the 101st is the only air assault division in the world. Nobody else but the US Army can afford that many helicopters.

Alratan · May 14, 2009

I've included this in my competent Air Ministry TL, by butterflying away Cierva's death, so development is more advanced by the war.

IOTL the British had specifications issued, but they were cancelled admidst the panic of going to war and the Fall of France.

Magniac · May 14, 2009

tallwingedgoat said:
{Originally Posted by Landshark:
It's not about moving them cheaply, it's about moving them effectively. Gliders were used because they negated the scattering problem you had with paratroops. A more developed autogyro could have doen the same thing but wouldn't have been dependent on towing aircraft and wind currents like a glider.}

Still if you had to move a 12,000 man division and an autogyro can move maybe 6 guys at a time, economics does come to play.

Even today the 101st is the only air assault division in the world. Nobody else but the US Army can afford that many helicopters.

Economy of scale wouldn't have been that big a problem for the US, I can see them having at least one 'rotor infantry' battalion in the 82nd Airborne by the time of the invasion of Italy. Range would be a problem for those across-water-invasions in Europe, I guess.

CDurham · May 14, 2009

I believe the Japanese army did use them for artillery spotting

But another thing is, look at the type of autogiros they had, mostly 1 or 2 person craft that were seen as having a limited use.

Magniac · May 14, 2009

Alratan, sorry, I hadn't read your TL as far as the introduction of the autogiro into British service. Because of my lack of optimism for the post-war Gyrodyne tech you've brought forward in 'For Want...' to work in WWII I think it best for me to comment on this thread.

Alratan said:
August 1939: Avro delivers the first example of its new rotorcraft, the Avro Gyrodyne (the Fairey FB-1 of OTL, accelerated by the survival of Juan de la Cierva and Lord Londonderry slightly shifting focus from quantity to quality)

Wiki says that the the FB-1 had the ability to hover, and that this was the result of power being transferred from the engine to the main rotor. I think the simpler autogiro/gyroplane designs of the pre-war era, where the only power given to the main horizontal rotor blades was for the pre-rotation necessary for jump take-offs, are more plausible for largescale WWII service. Anything too 'helicoptery' would just take too long to develop, and would only be adopted at the end of the war, IMHO.

Alratan said:
With Cierva surviving and the Air Ministry
issuing their Gyrodyne specification earlier, it means that they were in production by Avro before the Fall of France, so weren't cancelled. I've had them used as air-sea rescue during the Battle of Britain and as pilot rescue in Norway, but what else do we see happening in this field. With both the Germans and the British both operating rotary craft in the same theatre, it is likely that they will each see examples of the others, and maybe even capture damaged verisons. I'm planning on have an order for more and a new specification be issued by the Air Ministry in July, after the demonstation of their usefulness in Norway. What other uses do we think they could have been put to. I'd expect that the Commandos would have become intereted in
them, but they may not have been capable of to much at this stage.

The Dean said:
I hadn't thought about VTOL but of course that's significant. With Cierva surviving in TTL rotorcraft development could take a completely different course and we could get to the tilt rotor concept via the compound gyroplane very quickly. Juan Cierva was never a helicopter enthusiast regarding them as overcomplicated. He was trying to make an unstallable aircraft so it was ironic that he was killed in a takeoff accident caused by stalling.With the success of the Gyrodyne I could see the much larger Rotodyne being developed in the transport role. Pure helicopters would be in a minority only used for specific roles as they would be less fuel efficient.

I think the point The Dean makes about efficiency is the key to understanding why basic autogiros were not a bad idea for militarisation in WWII. That this militarisation barely happened, with the Germans only adopting observation gyroplanes for their naval forces, is a real mystery. Eventually there would be more helicopters used in the war! Why? Is it because of the death of Cierva, as historians claim? Is it because the ideal of the powered horizontal rotorcraft (helicopter) was so strong in the world's aircraft industries that unpowered horizontal rotors were considered unsound?

It certainly wasn't because said industries could foresee that helicopters would make gyroplane technology obsolete. If they could, then they could also see that jets would make prop fighters and bombers obsolete, and I don't think that any such consensus existed at the beginning of the war about what was, after all, the main aeronautical science.

It must have been a case of there just being no doctrine (or imagination to invent a doctrine) for the use of VTOL craft.

Alratan said:
If the Air Ministry is willing to release some of these aircraft to Army Co-operation Command, rather than keep them limited to pilot rescue, we could see some interesting developments. I suspect that if the Commandos want some, they'll get them, given Churchill's sponsorship of them. If we do see larger transport Gyrodynes appearing in, say, early 1944, it would be interesting to see what the Comandoes and SOE get up to with them.

As for Army Co-operation Command, these were the same people who retired the Westland Lysander (Britain's answer to the Fieseler Storch) from combat service against the heer after Dunkirk and the early North African campaigns. It was the SOE who used these excellent VSTOL aircraft to ferry their agents into France until '44. I can't find any reference to their use in Europe in the major campaigns of '43-'45, although they were used in Burma during this timeframe.

I think the creation of a VTOL doctrine for forward co-operation and transport was all that was needed for this tech to be adopted, though probably the Americans were the only ones with the industrial might to make such a doctrine work. Cierva lives and goes to Washington, formally joining Pitcairn in a business partnership? They then successfully lobby the US army and navy?

Alratan · May 14, 2009

Magniac said:
Alratan, sorry, I hadn't read your TL as far as the introduction of the autogiro into British service. Because of my lack of optimism for the post-war Gyrodyne tech you've brought forward in 'For Want...' to work in WWII I think it best for me to comment on this thread.

Fine with me.

Wiki says that the the FB-1 had the ability to hover, and that this was the result of power being transferred from the engine to the main rotor. I think the simpler autogiro/gyroplane designs of the pre-war era, where the only power given to the main horizontal rotor blades was for the pre-rotation necessary for jump take-offs, are more plausible for largescale WWII service. Anything too 'helicoptery' would just take too long to develop, and would only be adopted at the end of the war, IMHO.

From what I can tell, the Fairey FB 1 is simply an implementation of the Cierva C.41, which was designed pre war, a specification to produce it was issued in 1938, but was delayed by the start of the war and then cancelled in the panic after the fall of France.

I think the point The Dean makes about efficiency is the key to understanding why basic autogiros were not a bad idea for militarisation in WWII. That this militarisation barely happened, with the Germans only adopting observation gyroplanes for their naval forces, is a real mystery.

I think it's essentially chance that helicopter manufacturers and designers were quicker to market and captured the mind share of the public and military.

It certainly wasn't because said industries could foresee that helicopters would make gyroplane technology obsolete. If they could, then they could also see that jets would make prop fighters and bombers obsolete, and I don't think that any such consensus existed at the beginning of the war about what was, after all, the main aeronautical science.

I'd argue that gyroplanes aren't obviously inferior to helicopters in many applications, indeed, they can be superior. Of course, now helicopter development is a long way in advance of gyroplane, so it's too big a disadvantage.

It must have been a case of there just being no doctrine (or imagination to invent a doctrine) for the use of VTOL craft.

Pretty much.

As for Army Co-operation Command, these were the same people who retired the Westland Lysander (Britain's answer to the Fieseler Storch) from combat service against the heer after Dunkirk and the early North African campaigns. It was the SOE who used these excellent VSTOL aircraft to ferry their agents into France until '44. I can't find any reference to their use in Europe in the major campaigns of '43-'45, although they were used in Burma during this timeframe.

In my TL, Army Co-operation Command is going to evolve very differently. Continuing operations in Norway make VTOL aircraft much more useful - and Commanos and SOE will prove the first adopters for combat use.

I think the creation of a VTOL doctrine for forward co-operation and transport was all that was needed for this tech to be adopted, though probably the Americans were the only ones with the industrial might to make such a doctrine work. Cierva lives and goes to Washington, formally joining Pitcairn in a business partnership? They then successfully lobby the US army and navy?

On a mass scale perhaps. The way I see it going is that the British will prove the concept, which will then be picked up by the Americans and licensed.

Magniac · May 14, 2009

CDurham said:
I believe the Japanese army did use them for artillery spotting

But another thing is, look at the type of autogiros they had, mostly 1 or 2 person craft that were seen as having a limited use.

Not necessarily. The Fairey Rotodyne was about the size of the Osprey tilt wing, though it was built with fifties technology.

But this Pitcairn gyroplane could have paved the way, even though the five examples of the model were manufactured in nineteen thirty-three, before the jump take-off facility could be incorporated in the standard machines.

Fiji · May 15, 2009

the Germans experimented with autogiro spotters for their U-boats
problem was that you could only use them in calm waters, the sub had to travel at (or near) flank speed and it took a while to set the thing up and pack it up again ... in fact, standard procedure was to cut the autogiro (and pilot) loose and just divedivedive in case the scheisse hit the fan

they abandonned the concept rather quickly

Dr. Strangelove · May 15, 2009

I had the idea to butterfly away De La Cierva's death in No Spanish Civil War and have him move to the US and collaborate with Igor Sikorsky: this would lead to helicopters being used by the allies to help them cross the Rhine in the last months of the war. In the end I forgot about it completely until I read this post.

Alratan · May 15, 2009

Cierva wasn't interested in helicopters, and if he survived to work on them, Gyroplanes are probably better for the job they need to do

perfectgeneral · May 15, 2009

tallwingedgoat said:
Still if you had to move a 12,000 man division and an autogyro can move maybe 6 guys at a time, economics does come to play.

Even today the 101st is the only air assault division in the world. Nobody else but the US Army can afford that many helicopters.

For reference, that is 281 helicopters, including 3 battalions (3 x 18) of Apaches. They claim to move 4000 150-kilometres into enemy terrain in one lift. That's 20 per transport/assault helicopter (11 x 18 = 216 Helos?) plus 54 Apache attack helicopters and 11 scouts, I would guess.

The UK joint helicopter command isn't far short of that, but it is short of that. It might be a worthwhile target to aim for. 24-36 more Merlins and 24 more Chinooks wouldn't hurt.

CDurham · May 15, 2009

Fiji said:
the Germans experimented with autogiro spotters for their U-boats
problem was that you could only use them in calm waters, the sub had to travel at (or near) flank speed and it took a while to set the thing up and pack it up again ... in fact, standard procedure was to cut the autogiro (and pilot) loose and just divedivedive in case the scheisse hit the fan

they abandonned the concept rather quickly

Also, autogyros caught out in the open would be vulnerable to any enemy fighter that saw them. They were slower and with a low ceiling and while they may or may not have been more manuverable it wouldn't have mattered as a fighter could just go a mile out and try for a second pass. Unless they saw the fighter first and managed to hide in a ravine (or something similar) they were dead.

Magniac · May 15, 2009

Alratan said:
Cierva wasn't interested in helicopters, and if he survived to work on them, Gyroplanes are probably better for the job they need to do

The Gyrodyne is an interesting concept, in that it is a fusion of the autorotation and powered rotation sciences. It's part autogiro, part helicopter, with the ability to power up or power down the main horizontal blades, depending on whether you want to fly it forward or hover. Basically, it maintains the ability of the gyroplane to rely on it's secondary blades to provide thrust, but it can also stand/fly in one place and let the main rotor 'drain the fuel tanks dry' (I like that definiton of powered hovering, I read it in one of the online pieces comparing the two technologies).

But... is the merger of autogiro/helicopter technology something that can be easily taken from drawing board to production using mid-century technology? The Fairey FB-1 was doing well in it's test in '48 and '49, but one of the prototypes crashed, killing both men on board. Is this fusion technology, at that time, as temperamental as the V-22 Osprey would later be?

CDurham said:
Also, autogyros caught out in the open would be vulnerable to any enemy fighter that saw them. They were slower and with a low ceiling and while they may or may not have been more manuverable it wouldn't have mattered as a fighter could just go a mile out and try for a second pass. Unless they saw the fighter first and managed to hide in a ravine (or something similar) they were dead.

Which is the danger NATO troops flying in Chinooks et al would have faced in NE Europe if the Soviets had ever dropped the hammer and a non-MAD war occurred (same for the Reds in their Hinds--if I remember my Clancyporn correctly the best late 20th century heilcopters can easily be taken down by a P-51 prop fighter armed with fifty cals).