Stability and Control characteristics of the Early Mark Spitfires

[CaptainDoggles]

Originally Posted by Martin

10. Off topic discussion - in full or in part. Purposeful and/ or continuous off topic discussion.

Here's a quote from another interesting sticky. Start another thread if you want to keep going.

[winny]

Originally Posted by Fenrir

Hey Win, here's the laymans...

Thank you for taking the time to explain it.. My head has stopped hurting!


I'm no aerodynamics expert, but I am a very keen amateur historian, BoB being my area of expertise. I'm inclined to agree with you. I've read many, many combat reports, memoirs, interviews written by the people who were there and it's hard to believe that this issue was widespread, or severe. I've never read of anyone complaining about it. Quill and Henshaw both mention problems they encountered whilst testing and this wasn't one of them.

[robtek]

I think the fact that you have to return the stick almost to neutral after entering a high g turn (>3 g) to prevent oversteering in a Spitfire should be in game, also the very sensible elevator with large reaction for small inputs and the roll rate as documented.
This will be a problem for ham-handed pilots, but a delight for the virtuosos, as it was in RL.
I don't see that as "porking" the Spit further, but to give it the characteristics that made it famous.
Every aircraft in CoD should reflect its pro's and con's as they where documented then.

[CaptainDoggles]

Originally Posted by robtek

I think the fact that you have to return the stick almost to neutral after entering a high g turn (>3 g) to prevent oversteering in a Spitfire should be in game, also the very sensible elevator with large reaction for small inputs and the roll rate as documented.
This will be a problem for ham-handed pilots, but a delight for the virtuosos, as it was in RL.
I don't see that as "porking" the Spit further, but to give it the characteristics that made it famous.
Every aircraft in CoD should reflect its pro's and con's as they where documented then.

+1

[robtek]

Sorry bongo,
but your posts can be more readily interpreted as
first: a attack on the person, not the post
and second: as the endeavour to keep the status quo of the spit controls.
You seem to be too much emotional influenced, imo.
But thanks anyway, for supporting my position.

[MiG-3U]

Ok, one more as I've been asked how to do the CoG calculation.

The dimensions can be found from the AB197 graph:

http://www.spitfireperformance.com/ab197datum.gif

and from page seven of the RM2535:

http://aerade.cranfield.ac.uk/ara/dl...rc/rm/2535.pdf

Lenght of aerodynamical mean chord (MAC): 78.54"
Location of datum line: 18.65" behind leading edge at MAC
Aft limit at MAC: 34% 26.7036" behind leading edge
Aft limit at wing root: 2.638' = 31.656" behind leading edge
CoG used by NACA: 31.4" behind leading edge at wing root

The rest is simple math:
Aft limit behind datum line at MAC: 26.7036" - 18.65" = 8.05"
Datum line behind leading edge at wing root: 31.656" - 8.05" = 23.6024"
NACA CoG behind datum line: 31.4" - 23.6024" = 7.7976"
NACA CoG location at MAC behind leading edge: 18.65" + 7.7976" = 26.4476"
NACA CoG % at MAC: 26.4476" / 78.54 * 100 = 33.6741%

Over and out.

[NZtyphoon]

Originally Posted by Crumpp

That empty weight CG for that specific aircraft then has its specific range for foward and aft limits based on its authorized configurations. That is why the weight and balance is part of the Pilot's Handbook for that aircraft. It is required documentation and just like the Handbook, propeller logs, engine logs, and airframe logbooks follows the aircraft throughout its life.

Originally Posted by Crumpp

The RAF did not have a Pilot's Handbook either, they had Pilot Operating Notes. Your post is nitpicky and irrelevant.

Crumpp, are you aware you are quoting, and disagreeing with yourself? And I agree, your post is nitpicky and irrelevant.

[winny]

NACA reports on the spitfire can be found here for anyone who would like to read the whole thing.

Downloadable PDF.

Edit: here's a very interesting document on Spitfire stalling characteristics. NACA again.

[Fenrir]

Originally Posted by robtek

I think the fact that you have to return the stick almost to neutral after entering a high g turn (>3 g) to prevent oversteering in a Spitfire should be in game, also the very sensible elevator with large reaction for small inputs and the roll rate as documented.
This will be a problem for ham-handed pilots, but a delight for the virtuosos, as it was in RL.
I don't see that as "porking" the Spit further, but to give it the characteristics that made it famous.
Every aircraft in CoD should reflect its pro's and con's as they where documented then.

These characteristics you describe are NOT representative of all Spitfires. Therefore they should NOT be in game. Read again my post on stability. It affected *some* - and it seems I need to remind some people here that does not mean all - Mk V aircraft. A Mk V is NOT a Mk I, or Mk II.

All I can suggest is that you guys go away and read the books I've read, go further make even more research and come back and make an informed opinion then. Please for pity's sake do not take the one single example of an agenda driven poster as gospel.

The NACA test discovered what they discovered - I can't argue with their findings, FOR ONE PARTICULAR AIRCRAFT. However I cannot agree that these are representative of the breed. And as for relevance, well, I've said it already. A Mk V is not a Mk I.

[CaptainDoggles]

Originally Posted by Fenrir

The NACA test discovered what they discovered - I can't argue with their findings, FOR ONE PARTICULAR AIRCRAFT. However I cannot agree that these are representative of the breed.

What is it about the tested aircraft that makes it not a representative sample of the other aircraft?