Stability and Control characteristics of the Early Mark Spitfires

[robtek]

Originally Posted by macro

If this was moddeled by robtek explaination could we not just get round it by making the joystick half as sensitive, if you know what i mean.
It would give unfair advantage over109 astheres is limited by how far the stick can move instead of pilot overpulling it
I am a fan of the spit,, i dont know an englishman who isnt.

In this case one wouldn't have the full deflection needed for a three pointer or in a really slow turn, i think.

[Glider]

Originally Posted by robtek

The pilots notes warn explicit that ripping of the wings is possible if not carefully flown.

The short stick travel and low force needed to get high g-loads are undisputed, aren't they?

The manual even say that the pilot has to brace himself not to get pilot induced over-g in bumby conditions.

If one pulls the joystick half the way back that would be equal to about 6 inches in RL -> as there is 3/4 inch for a 3 g load, which will even climb when not released immediately, 6 inches would either snap the wing, or result in a hi-speed stall with following spin, and blackout.

Other planes, i.e. 109, where the stick force and travel (lateral) are larger by far, should't react this way, as it is now.

Generally, a longer stick travel gives the pilot much more fine control, here in the pitch axis, and that should be modeled.

And there is no doubt that the pilots notes did what they were supposed to do, warn the pilots of potential issues and advise them how to avoid it. I did post a breaskdown of all the structural failures of Spits during the war

23,000+ spits built 121 failures, 22 due to a problem with fabric control surfaces, a number of others due to pilot error re use of oxygen, some due to engine fires.
How many flights do you think those 23,000 spits did during the war, no idea but easily in the millions. How many of those accidents were in training units again no idea but safe to assume a good proportion of the pilot error ones.

And you want to build something into the game to take the wings off in a tight pull up.

If you do this can we assume that you will agree to similar factors into the 109F and 109G both of which had serious issues with wing failure

[macro]

what i meant robtek was haveing different settings for the stick, say not very sensitive at near-center stick then more sensitive at the full back position, thus nulling out the intened sensitivity in the game whilst giving full range. The 109 wouldnt allow this as its modelled in game how the plane will move as it wasnt possible to pull the stick full back at speed as no pilot would have the strength to do so. basically an easy exploit (crap at explaining i know)


surely putting enough g on any plane and the wings will fold, just need to know how much for each plane but i would have thought this be a bit down the line to do this sort of dm considering its current problems

[Holtzauge]

Originally Posted by robtek

The pilots notes warn explicit that ripping of the wings is possible if not carefully flown.

The short stick travel and low force needed to get high g-loads are undisputed, aren't they?

The manual even say that the pilot has to brace himself not to get pilot induced over-g in bumby conditions.

If one pulls the joystick half the way back that would be equal to about 6 inches in RL -> as there is 3/4 inch for a 3 g load, which will even climb when not released immediately, 6 inches would either snap the wing, or result in a hi-speed stall with following spin, and blackout.

Other planes, i.e. 109, where the stick force and travel (lateral) are larger by far, should't react this way, as it is now.

Generally, a longer stick travel gives the pilot much more fine control, here in the pitch axis, and that should be modeled.

Sure you can pull the wings off but I don't think the data so far indicates it was a problem: Figure 12 b in the NACA Spitfire test gives the g-load gradient at 4.7 lb/g. Granted the curve does not go to really high g but assuming the gradient holds for higher loads as well and assuming a failure g-load of of 10-12 g that equates to a pull force of 47-56 lb needed to pull of the wings. So even if the actual deflection of the elevator was small you still needed quite a bit of hauling on the stick to pop the wings.

And remember that control without excessive deflection but by force input is practiced today: At the extreme was the F-16 which at some stage in development IIRC had a FIXED stick with no deflection at all. However, if memory serves me they had to introduce some some small deflection (1/16"?)in order to avoid PIO but essentially the control is by force input.

So frankly I do not see a problem if I need to pull all of 50-60 lb before the wings comes off: The porpoising that would result from flying in turbulence without wedging your arm would be annoying to be sure but you would hardly pull the wings off if you happen to sneeeze or fly through some rough air

[robtek]

Originally Posted by Glider

And there is no doubt that the pilots notes did what they were supposed to do, warn the pilots of potential issues and advise them how to avoid it. I did post a breaskdown of all the structural failures of Spits during the war

23,000+ spits built 121 failures, 22 due to a problem with fabric control surfaces, a number of others due to pilot error re use of oxygen, some due to engine fires.
How many flights do you think those 23,000 spits did during the war, no idea but easily in the millions. How many of those accidents were in training units again no idea but safe to assume a good proportion of the pilot error ones.

And you want to build something into the game to take the wings off in a tight pull up.

If you do this can we assume that you will agree to similar factors into the 109F and 109G both of which had serious issues with wing failure

As i've posted quite a few times, i want the documented quirks of all planes reproduced as close as possible.

And yes, i want the pilots in CoD also to heed the warnings of the pilots notes and fly accordingly.

In most planes it was nearly impossible for the pilot to reach the structural limit without trim, not so in the Spitfire, there it was comparatively easy to do that.

[Holtzauge]

Originally Posted by IvanK

You are the one who started this thread regarding real world Spitfire stability. In your opening post you tell us all that this is to be a discussion on Spitfire stabilty:

"This thread is going to cover the definable and measure stability and control characteristics of the Spitfire. It is not going to cover opinion outside of stability and control engineers.

What this thread is not going to do:

1. Get into a debate about "easy to fly". It is not definable and has no bearing on the measured facts.

2. It is not going to discuss the sustained level turning ability of the aircraft. That is also measurable and definable. For Example, anyone who is capable of doing the math will see that the Spitfire outturns the Bf-109 is steady state constant altitude turns at low velocity."

You then decide its an item for the bugtracker which deals with Sim behaviour. bugtrqacker is for bugs. The onus is on YOU as the thread starter and intended Bug tracker author to prove there is an issue in game.... so far you have not.

When you do make sure its in a definable,measurable and to an accepted standard.

+1

And let's not forget: "So then Mr Crumpp exactly what is wrong stability wise with the IL2 CLOD Spitfire MI I or II Ver 1.07.18301+Hot Fix ?"

However, knowing Crumpp's modus operandi I'm sure he's preparing something lenghty with lot's of red underlined quotes to pounce on the wing fold issue in order to extricate himself from the embarrasing stability issue....

[Glider]

Originally Posted by robtek

As i've posted quite a few times, i want the documented quirks of all planes reproduced as close as possible.

And yes, i want the pilots in CoD also to heed the warnings of the pilots notes and fly accordingly.

In most planes it was nearly impossible for the pilot to reach the structural limit without trim, not so in the Spitfire, there it was comparatively easy to do that.

Actually it wasn't that easy to reach the limit and lose the wing, if it was, more would have crashed. There was an issue later in the war with the wings bending and some reinforcement was introduced but that was when the Spit was being used as a dive bomber with a 1,000 lb payload. I don't think we can blame the pre war designers for not thinking of that scenario. details are in the 2TAF series of books by C Shore

Its also noticable that when the limit was reached the wings tended to bend and let the pilot get home, not break and bury the pilot in a hole in the ground. The Spit was designed with more flexability than most aircraft of the time. That should also be covered

I hope you agree that the foibles should include what the Germans thought of the Spitfire. Easier to fly, very easy to take off and land as well as being faultless in the turn.

[NZtyphoon]

Originally Posted by robtek

As i've posted quite a few times, i want the documented quirks of all planes reproduced as close as possible.

And yes, i want the pilots in CoD also to heed the warnings of the pilots notes and fly accordingly.

In most planes it was nearly impossible for the pilot to reach the structural limit without trim, not so in the Spitfire, there it was comparatively easy to do that.

So, there's also room for replicating the Spitfire's desirable stall warning and stall characteristics





It was well known that the Fw 190 was apt to flip upside down and crash at lower altitudes while attempting to recover from a dive, so IL2 might as well replicate that characteristic as well.

[CaptainDoggles]

Originally Posted by NZtyphoon

It was well known that the Fw 190 was apt to flip upside down and crash at lower altitudes while attempting to recover from a dive, so IL2 might as well replicate that characteristic as well.

Oh, you guys

I love it how for some people this is a red vs blue argument, so they make jabs at the 190 as if to "stick it" to the "blue guys".

Go back through the thread; comes up all the time.

[NZtyphoon]

Originally Posted by CaptainDoggles

Oh, you guys

I love it how for some people this is a red vs blue argument, so they make jabs at the 190 as if to "stick it" to the "blue guys".

Go back through the thread; comes up all the time.

Nope, I have nothing to do with red or blue - just pointing out that if Robtek wants to be consistent about aircraft control characteristics in IL2 replicating real life then there are lots of WW2 aircraft which had a problem with their handling.