4.101 RC - List of fixes

[PE_Tihi]

Originally Posted by jtd

no, that was aileron trim, and it has been changed.

loll!

[PE_Tihi]

Originally Posted by MD_Titus

the nose up tendency does seem rather exaggerated, wasn't it something to do with maximum cruise economy rather than combat cruise speed being used as the elevator trim neutral point?

In all probability it has to do with TD moving the CG back to reduce the plane's longitudinal stability, without adjusting the elevator angle to the long. axis (elevator trim neutral point as you put it)

The picture has been explained with more detail some two pages back, this thread.

[Fenrir]

Originally Posted by PE_Tihi

And you seem very sure you know what you are talking about? I studied aerodynamics, you know. Did you, or did the guy who threw me a bone, as you say?

Well then you surely must understand the principles of gyroscopic precession; the reason why when you push or pull the nose up or down in pitch you get a reaction in the yawing plane. The reverse is true too, you know, which is why:

Originally Posted by PE_Tihi

If the rudder or some other control is moved energetically to push the nose down in a stall climb, this causes slow ( ~ 0,7 Hz) and very strong pitch oscillations, (amplitude like 45 deg or more relative to the flightpath direction). They do not get damped to sufferable level before plane reaches something like 200 kmh in the dive. No other plane in the game behaves nearly so wild.

Ah, so now you talking about longitudinal stability, which has nothing to do with elevators; for what it's worth the later Spit marks were always somewhat behind the curve when dealing in vertical tail surface area with each progressive increase in power - so at low speed you don't have enough airflow going over the fin/rudder to provide adequate compensation for your power setting - no surprise, and until we get a pilot in here who can authoritatively comment on the planes behavioural characteristics under such flight conditions, we are gonna have to trust TDs judgement.

Originally Posted by PE_Tihi

As for the reasons why your Spit pitches up the nose wildly, almost certainly the reason is TD moving the CG backwards. CG position is the MAIN pitch stability factor. That s why the above happens. And I wrote that already here, a page or so back. Take a look at the picture there.

There are many reasons not just CofG for trim change, and if you'd studied aerodynamics as thoroughly as you claim, you'd know this. Trim change can be accomplished through airframe/fixed surface/moving surface design and even by the manner of mass balance - to accuse TD of moving the CofG position, well, you assume too much. Especially as the spits do not exhibit any of the other criteria to warrant an accusation of pitch instability.

Originally Posted by PE_Tihi

The effects are most obvious in slow flight, near stall; and still strong enough at combat speeds to spoil the aim. And the plane is instable laterally, too.

Wow, a 1600hp aircraft at slow speed tricky to handle? With little air moving over flight surfaces and a massive torque reaction?

Originally Posted by PE_Tihi

If you cannot see anything of the above in flight, I cannot help you further.

I see a little more longitudinal reaction to aileron input, but not catastrophic, I see a low elevator trim speed with no pitch instability, and bugger all instability laterally unless i'm flying with the rudder badly trimmed. Personally, I think you have controller issues, or you need practice to get the best out of the spit.

Originally Posted by PE_Tihi

What they sold you as a reason for the planes bad pitch trim, I do not know. After seeing their FM work here, I do not care, either.

They showed us all a pic of a modern day restored Spitfire flying in formation with a photo a/c at low airspeed with significant down elevator deflection.

Tihi, I suggest if you want people to listen to your issues then you provide quantifiable data or a series of pilot reports - and much more than one - that backup your arguments or that at least point to a common extrapolated outcome.

Currently you come here with nothing more than opinions delivered with a exasperating sense of melodrama and an irritatingly belittling attitude towards the guys at Team Diadalos - you win no friends and thusly make any chance that your grievances might be even investigated, let alone fixed, marginal at best.

[MD_Titus]

Originally Posted by JtD

No, that was aileron trim, and it has been changed.

ah right, but what about the change to the elevator trim, it does seem to take a lot more trim to maintain a level attitude at about 280-300kmh

the rest of the spit characteristics are fine imo, the aileron fix is appreciated and it seems... well, it seems to give more warning of a stall, and require flying properly. as this is the case, will "spitnoob" become a phrase of the past?!

[PE_Tihi]

Originally Posted by Fenrir

Ah, so now you talking about longitudinal stability, which has nothing to do with elevators;

You confuse the lateral and longitudinal stability; longitudinal certainly has to do with the elevators.

Originally Posted by Fenrir

"...almost certainly the reason is TD moving the CG backwards...
...."

There are many reasons not just CofG for trim change, and if you'd studied aerodynamics as thoroughly as you claim, you'd know this. Trim change can be accomplished through airframe/fixed surface/moving surface design and even by the manner of mass balance - to accuse TD of moving the CofG position, well, you assume too much. Especially as the spits do not exhibit any of the other criteria to warrant an accusation of pitch instability.

'Almost certainly' is an acknowledgement they may be other reasons. That is improbable because the much reduced longitudinal stabillity of the plane compared to 4.09. indicates the CG has been moved backwards relative to its 4.09 position.

You say in a previous post 'there is NO behavior AT ALL which indicates pitch instability. The a/c does NOT tighten up in turns..'
For the 'turn tightening' to appear, CG has to be BEHIND the plane AC, which would make the plane completely uncontrollable- ie. instable in the absolute sense. If that s your criterion for where the bad stability and handling begins, please better avoid flying your designs yourself

And if you see 'no pitch instabillity at all' here, then am not going to waste any more time explaining. I wrote enough in the thread.

"They showed us all a pic of a modern day restored Spitfire flying in formation with a photo a/c at low airspeed with significant down elevator deflection."
How on earth do you find this a proof of anything else, but the Spit having the movable elevators? Next second the elevators could 've been in another position. Or do you beleive formating pilots have orders against moving their controls?

Regarding the belittling attitudes, etc, please refer to your posts here. As for the TD, their job are not anyone's grievances; they took over modifying an FM in an acceptable manner.

[JtD]

Originally Posted by MD_Titus

ah right, but what about the change to the elevator trim, it does seem to take a lot more trim to maintain a level attitude at about 280-300kmh

the rest of the spit characteristics are fine imo, the aileron fix is appreciated and it seems... well, it seems to give more warning of a stall, and require flying properly. as this is the case, will "spitnoob" become a phrase of the past?!

A Spitfire V as tested by NACA went practically into stall with the elevator still depressed at about 4° (~25% of travel). It did a 3g turn at 170 mph with the elevator at about neutral. Think about that when you check in game behaviour.

The neutral trim point of the elevator trim can be set by the pilot in game, so I don't think it matters much. I just trim it down a lot on take off and then have more fun flying the thing than I ever had before.

[PE_Tihi]

Originally Posted by JtD

A Spitfire V as tested by NACA went practically into stall with the elevator still depressed at about 4° (~25% of travel). It did a 3g turn at 170 mph with the elevator at about neutral. Think about that when you check in game behaviour.

The neutral trim point of the elevator trim can be set by the pilot in game, so I don't think it matters much. I just trim it down a lot on take off and then have more fun flying the thing than I ever had before.

I could not visit the only site I could find reporting on this NACA Spit test you quote-the browser forbids the site as unsafe.(ww2aircraft.net)

Could you find any such data on the heavy trimming necessary on the Spitfire, from a British source? Like the spitfireperformance site, for example?

Engineers have been known of mounting the things upside down on unfamiliar foreign equipment, you know.

Any trimming increases drag, reducing speed. Not irrelevent to a transport, you see.

Ahm, what's this:

' "It happened that Wright Field had the only Spitfire in America-a Mark V. Unfortunately almost every pilot in the Air Corps had had a go on her and like a car that had too many drivers, she was the worse for wear...'She was very tired, very sloppy-she'd had the guts caned out of her all right."


NACA got it for testing after that.'

http://forum.axishistory.com/viewtop...91603&start=15


Hmm? How about looking at the sources that say the things you may not like , too ?

[MD_Titus]

Originally Posted by PE_Tihi

I could not visit the only site I could find reporting on this NACA Spit test you quote-the browser forbids the site as unsafe.(ww2aircraft.net)

Could you find any such data on the heavy trimming necessary on the Spitfire, from a British source? Like the spitfireperformance site, for example?

Engineers have been known of mounting the things upside down on unfamiliar foreign equipment, you know.

Any trimming increases drag, reducing speed. Not irrelevent to a transport, you see.

this is incorrect. you use trim as it has a lesser drag penalty than using stick controls. a correctly trimmed plane should fly faster than the same plane being kept level using pilot input, no?

JtD - as for neutral trim point being settable in game, how would i go about doing this, or do you just mean dialing in trim for straight and level and that is the neutral point?

[PE_Tihi]

Originally Posted by MD_Titus

this is incorrect. you use trim as it has a lesser drag penalty than using stick controls. a correctly trimmed plane should fly faster than the same plane being kept level using pilot input, no?

JtD - as for neutral trim point being settable in game, how would i go about doing this, or do you just mean dialing in trim for straight and level and that is the neutral point?

If you 'turn' the whole horizontal stabilizer plane to get the plane in trim for its 'most important' flight regime (certain airspeed), you get less drag at that speed than by deflecting the elevator by a trim tab, increasing the elevator airfoil chamber.

This is one reason for 'flying tails', too.

Accordingly, it would have been quite sloppy from Supermarine to deliver such a plane NACA is talking about. It would mean the drag in order to neutralize the wing-lift moment (trim drag) is higher than neccessary.

[Fafnir_6]

Originally Posted by MD_Titus

will "spitnoob" become a phrase of the past?!

Yes.

Having seen some of the comments from TD since 4.10 came out, my understanding is that the other n00b uberwarbirds in the game will be served with the same/similar treatment in 4.11 or future releases. I think they would have liked to fix these others as well but TD has limited resources, so it may wind up being only one uberwarbird at a time getting fixed (the spitfire just had the bad/good luck to be the first to get fixed). I also know that DT is painstaking in their compliance to the available references and will not make a change unless new reference material becomes available. To those of you who are complaining about the spits in 4.10/4.10.1, your best, only hope is to find a verifiable document from a relevant authority that outlines any change you think should be applied. Submit these respectfully to DT and I'm sure you will see something come of it. I personally think (as do many here) that the 4.09 spit needed to be fixed (hence the "spitnoob" name-calling) and that DT has done a masterful job of it. It still sucks to get owned by LA-7 drivers and such online but I have a feeling they are about to get a short drop back to reality as well .

Cheers DT and thanks for another masterpiece,

Fafnir_6

P.S. Much about the content of upcoming DT patches can be revealed when a DT member posts here. I'd advise anyone with an interest in such things to PAY ATTENTION when someone like Viikate, FC99 or Caspar posts in these forums, the future will reveal itself (it also helps to be respectful and friendly towards our patchmakers). Il-2 4.11 is gonna rule .