Stability and Control characteristics of the Early Mark Spitfires

[Crumpp]

the British, with the likes of William Lanchester, were pioneers in laying down scientific principles for aeronautics,

You are confused about this whole subject. Of course, there were some brilliant British engineers.

What does he have to with an adopted measureable standard for stability and control????

You understand, an engineer in the United States or German designing a fighter could go look to see the measured characteristics that he must meet.

Gates was the British engineer who tried to shoulder that task of getting the Air Ministry to adopt a measureable standard. He eventually achieved it in the post war.

[taildraggernut]

So why was the Mustang III considered longitudinaly unstable too?

[winny]

So, now all we need is the same data for a MK I and II.
Because, correct me if I'm wrong, they didn't test them at NACA.

I'm pretty sure that if I came on here saying that the 109 E was wrong, and used an F or G's data I'd get laughed out of here. Especially by you.

So I'd like some hard data on the same phenomenon in I's and II's, please.

Thanks.

Edit: and bear in mind that the spitfire in lanes docs is around 300lb lighter than a spit in BoB trim.

[robtek]

Originally Posted by winny

So, now all we need is the same data for a MK I and II.
Because, correct me if I'm wrong, they didn't test them at NACA.

I'm pretty sure that if I came on here saying that the 109 E was wrong, and used an F or G's data I'd get laughed out of here. Especially by you.

So I'd like some hard data on the same phenomenon in I's and II's, please.

Thanks.

Edit: and bear in mind that the spitfire in lanes docs is around 300lb lighter than a spit in BoB trim.

The airframe of the Mk Va is similar to the Mk I and II

[taildraggernut]

Originally Posted by robtek

The airframe of the Mk Va is similar to the Mk I and II

is similar a good enough benchmark? even the Mk9 airframe was similar.

I think Winny's point is valid, would it be accepted if the aircraft being analysed was a 109?

[CaptainDoggles]

Originally Posted by taildraggernut

is similar a good enough benchmark? even the Mk9 airframe was similar.

I think Winny's point is valid, would it be accepted if the aircraft being analysed was a 109?

IMO, the difference between a MkII and a MkV is much less than the difference between a 109F and a 109G.

My understanding is that a MkV is basically just a MkI but with a Merlin 45. True?

By contrast, the 109F is drastically different, structurally speaking, from the 109E. Different wings, different tail empennage, lack of wing guns, different engine cowling, etc.

If we were talking about, say, Fw 190A variants it might be a different story.

[taildraggernut]

My understanding is that a MkV is basically just a MkI but with a Merlin 45. True?

in very basic terms yes, but there were relatively significant differences, the bob weight, but even an engine change makes it a different beast, it performs differently it is loaded differently, the pilot's notes between the 2 reflect that, so I don't think it's a fair comparison at all.

[winny]

Originally Posted by CaptainDoggles

IMO, the difference between a MkII and a MkV is much less than the difference between a 109F and a 109G.

My understanding is that a MkV is basically just a MkI but with a Merlin 45. True?
.

It's essentially a MK I airframe, yes. There are differences though.
The airframes were strengthened (I must admit I don't know what this involved)
The radiator scoop under the wing is bigger, and there was a difference in weight .
MK V's had the inertia weight fitted into the elevator system as well. There's also a difference between early V's and late V's, they got heavier as more mods were added.

It's all a bit confusing, I've got Crumpp saying that the stall is horrid and yet I've got a NACA report on the Spitfire stall that says that it has the best stall characteristics of any fighter they had tested and that they were 'desirable'

The other problem I have with this whole argument is that there is no data for the same tests on any of the other a/c in the game (AFAIK). How many WW2 aircraft would have also been considered unstable by NACA?

[JtD]

It was designed for a load factor of 10, not 6. Calculation showed wing to be the weakest point, it was tested and met specification. Specification was changed to 12 for later marks.

[NZtyphoon]

Originally Posted by Crumpp

You are confused about this whole subject. Of course, there were some brilliant British engineers.

What does he have to with an adopted measureable standard for stability and control????

You understand, an engineer in the United States or German designing a fighter could go look to see the measured characteristics that he must meet.

Gates was the British engineer who tried to shoulder that task of getting the Air Ministry to adopt a measureable standard. He eventually achieved it in the post war.

Wrong again, Lanchester's work on aerodynamics, as well as other British academics, provided a basis for the adopted measurable standards for stability & control worldwide - the British did indeed have such standards, and adopted them well before NACA; to claim that only the Americans and Germans had such standards is farcical. Read the articles and do some historical research of your own before making such claims. What work, for example, did the National Physical Laboratory in Britain do during WW1? http://www.npl.co.uk/about/history/

The Duplex wind tunnel was completed in 1919. It had a cross-section of 2 m by 4 m.

During the first world war, activity in aerodynamics expanded dramatically and NPL made major contributions to advances in theoretical and practical aspects of the stability of aeroplanes, airships, kite balloons and parachutes. Techniques had been developed for testing scale models of wings, ailerons, propellers and of complete models of aeroplanes in wind tunnels.