Contra rotating propellors

[agent 009]

Or a good belly shot of the Spiteful would be good.

[Angus]

Giggle this link:
http://1000aircraftphotos.com/APS/2918.htm

And.....if it works....





Anyway....




And then....


Well, the link:
http://www.supermarine-spitfire.co.uk/the_spiteful.htm


Goodnight

[Crumpp]

Angus,

Performance figures for RB518 are on page 501 of Shacklady and Morgan's book "Spitfire:  The History".  I can scan it and post them if you do not have the book!

All the best,

Crumpp

[Krusty]

Well there's your reason it was a flop: It's butt-ugly!!

[Angus]

Well, the old wing is prettier, but this wing gives more speed.
Crumpp: I'd be very grateful if you'd scan and post. Take your time, for I am quite busy this time of year, and have little time of my own, - except when I am pretty well exhausted. Well, you're from the rural background, so you pretty much know it!
BTW, I also have some books that you probably don't have, probably they are more or less from the brits, but I have some German ones as well. If you are looking for anecdotes from, say, some particular part and theater of the war, just define it, and I'´ll see if I have some. I'll be quick about the business.
To keep this thread alive, and feed some to the ever-waking eye of HTC, I'd appreciate if you'd drop me a mail, I'd respond with a post, - here

Well, all the best folk

[Kurfürst]

Originally posted by Krusty
Well there's your reason it was a flop: It's butt-ugly!!

Reminds me of an offspring from a Spit humped by the Stang, too. The parents are OK on their own, but their kid looks just odd.

[pasoleati]

Well, some thoughts:
-in the Spitfire Story there is the test report on Spit with the contra-prop and the pilot´s findings are exceptionally positive
-in Putnam´s Supermanrine aircraft tome it is mentioned that the 20-series Spit rolled at 120 deg/sec at 300 mph IAS
-had e.g. the F4U been fitted with a contra-prop, vast number on landing accidents would have been avoided

[Rafe35]

Originally posted by pasoleati
-had e.g. the F4U been fitted with a contra-prop, vast number on landing accidents would have been avoided

Where did you get this information from?

I actually never ever heard about contra-propeller fitted into F4U/FG Corsair and there's a early prototype XF4U-4 has 6 Blade Prop, but project abandoned, but for Contra-Prop on F4U/FG, I never heard of it.

[Kurfürst]

Originally posted by pasoleati

-in Putnam´s Supermanrine aircraft tome it is mentioned that the 20-series Spit rolled at 120 deg/sec at 300 mph IAS

Probably true, as afaik the 20series had redesigned wings which fixed the old problem with the spitty wings flexing too much in rolls and causing some 65% reduction in roll rate as per NACAs report on lateral control. Too bad that it was practically not fixed until post-war, I wonder what took the Brits 10 years that the wing has serious rigidity problems.

I wonder if the other lateral problem of the Spits were fixed with the 20 series, namely the so excessive aileron forces that prohibited the full deflection of the aileron above as litle as 140 mph IAS, even if both hands were used. As a result max roll rate was somewhere about 70-80 deg/sec, and fell steeply with speed increase. But from memory, 4x series Spitties were still heavy on the ailerons. Yet, 50-60% of improvment is readily believable if they brought up the wings to the typical scale of rigidity of other fighters of the time, ie. ca 30-40% roll loss to flexing - even if the controls were still that heavy.

[Angus]

Watch out here a little....
70-80 deg pro sec is actually almost uncomfortably good.
And once the wing was merely clipped, which has rather little to do with rigitity, the humble Spit V rolled close to the 190...

Now, 120 deg/sec is very very fast. I have a lower number for the Seafire47, - 67 degrees or so, but it could be the min number as well.

Makes one wonder what a corsair with a contra prop could have done.....

[Kurfürst]

Originally posted by Angus
And once the wing was merely clipped, which has rather little to do with rigitity, the humble Spit V rolled close to the 190...

Unfortunately angie it never did, the improvement was marginal and the pilots were against it. How many clipped spits were around, not many, guess why. It didnt help much. I can send the docs over if u r interested.

[pasoleati]

Originally posted by Rafe35
Where did you get this information from?

I actually never ever heard about contra-propeller fitted into F4U/FG Corsair and there's a early prototype XF4U-4 has 6 Blade Prop, but project abandoned, but for Contra-Prop on F4U/FG, I never heard of it.

Didn´t you note the magic words HAD IT BEEN FITTED? From basically every account it can be deduced that contra-prop would have eliminated the main cause of F4U accidents, torque roll at low speed (such as wave-off).

K, I wonder when the Willy M fixed the control forces on the 109? AFAIK even the K had very excessive stick force per g. And don´t repeat the manure about "flying with the trimmer".

[gripen]

Annappas pasoleati mailiosoite niin saat vähän aineistoa.

gripen

[pasoleati]

Gripen, tässäpä se on: paso.leati@pp.inet.fi

[Angus]

Oh, dear.
"Unfortunately angie it never did, the improvement was marginal and the pilots were against it. How many clipped spits were around, not many, guess why. It didnt help much. I can send the docs over if u r interested"

I belive the improvement plonked the clipped Spitty roughly in the 3rd seat of WW2's finest rolling fighters, exceeded by the F4U and the scorer, - da 190!
Some late US fighters also rolled well, like the late P38, so I would not swear on that for 1945, but for 1942, well, 190, F4U and Spit V clipped were the best rollers of the game.
AFAIK, but please post if you can.
The pilots did not overly like the clipped ones, - they were faster and rolled well, but stalled worse and had a poorer ROC and climb as well as high alt performance. NATURALLY
I remember you quoting turning performance from Clostermann vs 109F's, - I dug it up, - he was flying a clipped Spitfire.
So, where and when does what suit M8