[NO BUG] The PITCH...

[Anatoli-Kagari9]

Sorry to bring this again, but a recent post at another thread re-opened the question of there really being something wrong with the pitching up moment / tendencies in the K-4...

 

1) Use a modified "free flight" startup situation where you edit in the Mission editor to empty the fuel and the mw50 tanks...

 

2) Start the SITU

 

---> The pitching up moment still there: you'll be gliding, and unless flaps and/ or gear are deployed, tail-heavy trim settings can't be used without you having to fight the pitching up moment...

 

Even at full flaps and gear down, don't even think you can use more than -1,5 or -2,0 on your trim wheel....

 

Something must be wrong, I think ?

 

The CoG couldn't be further fwd, the prop effects are gone ( yes, I know in DCSs FDM p-factor is still playing it's tricks in this situation... ), there's no power, ...., doesn't make sense to me :-(

Edited January 5, 2016 by jcomm
title 1.1

[NineLine]

Free flight missions are tough to test on because most times most times your controls are zeroed compared to where they might be if you flying under those same conditions.

 

I swear though, if this is just another trim thread I will scream... I can jump into a free flight mission, adjust to where my controls and trim need to be, and fly level no issue. I can try with different conditions, but honestly... its a dead horse... again.

[Anatoli-Kagari9]

Free flight missions are tough to test on because most times most times your controls are zeroed compared to where they might be if you flying under those same conditions.

 

I swear though, if this is just another trim thread I will scream... I can jump into a free flight mission, adjust to where my controls and trim need to be, and fly level no issue. I can try with different conditions, but honestly... its a dead horse... again.

 

I have to disagree because, as much as I myself thought it was indeed a dead horse, truth is I had never ran the tests with empty fuel and MW50 tanks. To be honest, I even completely neglected the importance of a filled MW50 tank, which resides behind the pilot seat, and if full should play it's role in bringing the CoG back...

 

On empty tanks I believe any 109 will naturally be nose heavy, so, when we have a trim wheel with settings from -6 ( full tail heavy ) to +2 ( full nose heavy ), it surprises me that I can seldom go bellow -1 to fly without my aircraft wanting to pitch up, even when it is flying like a glider, and there are no gusts or updrafts being modeled in the sim.

 

The difference, at least for me, resides exactly in that detail - now the aircraft has it's tanks empty, and still feels tail heavy ?

Edited January 5, 2016 by jcomm

[5tuka]

Nice you run those tests Jcomm. My question is at which airspeed amd pitch attitude (roughtly in degrees) you encountered this pitch up moment?

 

@ Sithspawn I don't think it's an issue with trim since the pitch moment is related to the pitch angle of the aircraft. If you fly level or with negative pitch angle full downtrim is enought to stay level or even descent with centered stick. Things get hairy when holding a small positive pitch angle. Thats at least ehat I can tell from my own tests.

[Vitesse2l]

Does a bomb load make any difference in the test?

[Anatoli-Kagari9]

Does a bomb load make any difference in the test?

 

With fuel in tanks, it doesn't, but I will repeat my empty tank tests with and without a bomb, and amno, as well as flying the aircraft at different speeds / AoA as per 5tuka suggestion above.

 

Meanwhile, I have contacted the Messerchmitt Museum :-) - Let's see if I am lucky enough to get an answer... Should I get any answer, I will post the contents of my email

as well as those of their answer.

Edited January 5, 2016 by jcomm

[NineLine]

With fuel in tanks, it doesn't, but I will repeat my empty tank tests with and without a bomb, and amno, as well as flying the aircraft at different speeds / AoA as per 5tuka suggestion above.

 

Meanwhile, I have contacted the Messerchmitt Museum :-) - Let's see if I am lucky enough to get an answer... Should I get any answer, I will post the contents of my email

as well as those of their answer.

 

What question are you asking a museum?

[Anatoli-Kagari9]

What question are you asking a museum?

 

Not the Museum itself :-)

 

I'm trying - we do not have a 109 pilot around here...

 

And, please bare in mind I've been - actively - flying for some years (more than 35) ... for real, even if "just" gliders :-) so, I guess I know what and how to ask, specially when the subject is a PC-based flight simulation and not a real aircraft...

Edited January 5, 2016 by jcomm

[NineLine]

Yo-Yo has talked to a couple... one from WWII and one modern day.

 

Imagine everyday at work your ability to do your job was debated in open forums... fun right?

[Anatoli-Kagari9]

Yo-Yo has talked to a couple... one from WWII and one modern day.

 

Imagine everyday at work your ability to do your job was debated in open forums... fun right?

 

 

Mine is, not at the forums, but at the office...

 

And, why should debate have that negative grain you're putting on it ?

 

I do not doubt that Yo-Yo is doing his work with dedication, and great effort to bring it up to the standards he has provided us with the final p51d, and the Fw190, but AFAIK, the K-4 is still work in progress - it's in Beta - so, I guess all contributions to make it as perfect as possible when released look positive to me.

 

Then, as much as I like the K4 which happens to be the only module I am presently using with DCS, I also think there is something weird about it's tendency to pitch up, and, just as 5tuka pointed out, it is not necessarily any problem with the pitch ( stabilator ) trim... I don't know what it is - it simply doesn't feel plausible sometimes.

 

And I have used it just as you describe sometimes, setting the trim at a practically fixed position for the whole "flight" and being able to use the aircraft without much problem, but, when some conditions are met, the pitching up moment is there again, and I would really like to find out why ?

 

Of course it can be a native characteristic of this particular aircraft, and Yo-Yo in one of his recent posts wrote, exactly, "why don't you listen to Klaus Plasa"...

 

Believe me I would feel even more happy if I could find that these pitching up moments are indeed there because they're absolutely accurate and according to the real thing.

Edited January 5, 2016 by jcomm

[NineLine]

 

Believe me I would feel even more happy if I could find that these pitching up moments are, indeed there because they're absolutely accurate and according to the real thing.

 

But you guys dont want to listen to a man who has sat down with 109 pilots and poured over pages and pages of 109 documents (many not readily available on the internet). I really dont understand the mind set of it all... and if you go through stuff like this in your work life, I feel sorry for you, its not the way it should be.

 

Bottomline, Yo-Yo has already addressed this and many other issues, just because you all of a sudden have a gut feeling something is wrong doesnt really warrant a thread, so I will close this, if/when you get real evidence of an issue you can PM me and we will see about reopening it.

 

I hate having to repeatedly close threads, but when its already been addressed then it really is my only option.