Neglected/incomplete flight model?

[Jarlerus]

Ergo, if the lift is not enough to maintain flight (and therefore to produce a force that is at least equal and opposite of 1g in the vertical axis), how can it be enough to produce 2g?

 

Are you arguing that an airplane in a stall can't have any G-forces acting on it? :huh:

(G-forces are a result of accelerations - positive or negative)

[swatstar98]

Are you arguing that an airplane in a stall can't have any G-forces acting on it? :huh:

(G-forces are a result of accelerations - positive or negative)

In a stall only negative.

[Jarlerus]

In a stall only negative.

 

In a stall, where the direction of travel of the aircraft is downward (pilots perspective) the aircraft is essentially a big air brake. So the aircraft decelerates, and that generates G-forces. A negative acceleration, but an acceleration nonetheless, and the G-meter will show this.

[swatstar98]

In a stall, where the direction of travel of the aircraft is downward (pilots perspective) the aircraft is essentially a big air brake. So the aircraft decelerates, and that generates G-forces. A negative acceleration, but an acceleration nonetheless, and the G-meter will show this.

 

 

 

You are repeating what I said, negatives Gs

 

 

Enviado desde mi iPhone utilizando Tapatalk

[Whisper]

"It is abandonware", "it is pre-release", "it is looney tune physics", "it is hilarious".....

 

When asked where all the wrongdoings are:

"- It pushes 2G when stalling...

- And .. ?

- that is all, it pushes 2G when stalling".

 

 

Yet again, another useless out of enveloppe issue being blown out of proportion.

Actual impact on gameplay? I fail to see.Who is going to ab-use it, who is going to be unable to fly the Mig21 in a proper way because of this? I fail to see.

Would it be nice to see it corrected? SURE, and thank you for bringing the issue up.

Is that game/FM breaking? Hardly.

 

Keep things in perspective, please. Or will you explain to me that having 2G in stalls completely prevents the DCS Mig21 to be flown close to real in normal envelop and breaks the plane limitation that must be followed?

[Jarlerus]

You are repeating what I said, negatives Gs

 

 

Enviado desde mi iPhone utilizando Tapatalk

 

There's a difference between "negative G's" indicated in an aircraft (as in -2G when you pitch down hard), and negative acceleration though (a decrease in speed). The G-force in a stall are oriented in the same direction as G-forces in a turn.

[swatstar98]

There's a difference between "negative G's" indicated in an aircraft (as in -2G when you pitch down hard), and negative acceleration though (a decrease in speed). The G-force in a stall are oriented in the same direction as G-forces in a turn.

 

 

 

Okay, think about this. When u are un stall, and keep that situation you Will falla like a rock, that s not an negarive acceleration.

 

 

Sent from my Gazelle in autohover using Tapatalk

[Jarlerus]

Okay, think about this. When u are un stall, and keep that situation you Will falla like a rock, that s not an negarive acceleration.

 

 

Sent from my Gazelle in autohover using Tapatalk

 

Yes it is, if your speed is decreasing. (But once you are traveling along at a constant speed, you are not accelerating, nor decelerating anymore - and the G-meter should read ~1)

Edited October 25, 2018 by Jarlerus

[bkthunder]

"It is abandonware", "it is pre-release", "it is looney tune physics", "it is hilarious".....

 

When asked where all the wrongdoings are:

"- It pushes 2G when stalling...

- And .. ?

- that is all, it pushes 2G when stalling".

 

 

Yet again, another useless out of enveloppe issue being blown out of proportion.

Actual impact on gameplay? I fail to see.Who is going to ab-use it, who is going to be unable to fly the Mig21 in a proper way because of this? I fail to see.

Would it be nice to see it corrected? SURE, and thank you for bringing the issue up.

Is that game/FM breaking? Hardly.

 

Keep things in perspective, please. Or will you explain to me that having 2G in stalls completely prevents the DCS Mig21 to be flown close to real in normal envelop and breaks the plane limitation that must be followed?

 

LOL! if you consider a simple stall to be out of envelope.... well.

Have a good one fellas, I've contributed enough to this useless thread :thumbup:

[bkthunder]

Yes it is, if your speed is decreasing. (But once you are traveling along at a constant speed, you are not accelerating, nor decelerating anymore - and the G-meter should read ~0)

 

P.S. the g-meter in an airplane is measuring g-load on the vertical axis. If you're falling down vertically at a constant speed, the gmeter reads 1, because that's the force of gravity on the planet we live on. If it read 0, the plane would be floating, not falling. Stalling at 0g is imposisble by definition, because at 0g the airplane is weightless, and the wings don't carry any load (on top of that, you'd be on a parabolic trajectory with your AoA close to 0, so you couldn't stall anyway).

 

Depending on where the pilot / gmeter is sitting relative to the CG of the aircraft, you could experience some positive/negative or centrifugal g (for example in a flat spin or if the nose is oscillating up and down).

[Whisper]

LOL! if you consider a simple stall to be out of envelope.... well.

Have a good one fellas, I've contributed enough to this useless thread :thumbup:

 

Since when is stalling in any take-off, navigation, combat or landing procedure? Never

So in practice stall is something you actively avoid and you should spend zero percent of your flight time in it.

It's definitely an exception. So for exception cases, Mig21 exhibit a wrong 2G load. How is that going to impact 1) my day to day flying (I can easily answer this one : basically never), 2) impact how I get out of this exceptional condition (there, it may impact, but again, the only thing pointed out is this 2G factor, not how it negatively impact the normal procedure. Does it prohibit normal stall exit, for example? ) ?

Calling a FM broken on this single issue is what I call "way overblown".

[thrustvector]

i think for a while now there seems to be too much mig-21 bashing, it seems like a lot have just jumped on a bandwagon and forgot just how to have fun flying the plane.

as a lot have said, it wont interfere with your normal flying.

the plane is fine, I don't use it for MP, its a fun little module to fly, if you want one to be that exact go get a loan for 10 mill and by a proper simulator :)

[Jarlerus]

...the gmeter reads 1,..

Yeah, momentary brain-lapse. Corrected.

[Foka1]

Well, it's kinda hard to find data on an aircraft maintaining 2g during a stall... that's because maintaining 2g with a stalled wing is, as far as my common knowledge of aerodynamics goes, impossible.

I really don't think anyone should be explaining this to a developer who is suppsoed to prdouce a flight model, anyway:

 

The wing produces lift > the lift makes tha aircraft fly > the wing loading during normal flight is such that the weight of the aircraft is "supported" by the wing > during a stall the wing has (nearly) no lift, therefore the wing loading is lower than the weight of the plane > the airplane falls.

Ergo, if the lift is not enough to maintain flight (and therefore to produce a force that is at least equal and opposite of 1g in the vertical axis), how can it be enough to produce 2g?

 

 

So, can you explain how is this possible?

 

Initial post has ZERO data. even your comment has number "2G" and to which its related.

OP is just posted something which can't be point of reference for any investigation.. You get what I mean now?

[BadHabit]

Did some small tests last night, and the mig does not lock on 2g after stall.

 

It may jump momentary to 2 or more. but the rest of the stall is on -+1G. Tried flat spins, normal stalls and did some hard stalls that root from common low speed low alt maneuvering.

 

On the other-side the F-5 was locked on 2.7G on a stall but this could be me, holding the stick so I can remain in the stall.

 

 

Big thing that bothers me tho, is the aileron is 100% effective even at speeds the wings can not lift the plane no more and possible to do 360 degrees!

 

Where the F-5 will have very limited aileron effectiveness and mostly rudder must be used to roll the a/c.

[Wizard_03]

Developers have stated the FM is Complete and verified by both them and ED..cased closed.

 

 

https://forums.eagle.ru/showthread.php?t=222266

[Vitormouraa]

Developers have stated the FM is Complete and verified by both them and ED..cased closed.

 

 

https://forums.eagle.ru/showthread.php?t=222266

 

It doesn't mean it's 100% correct. There may be something incorrect, a bug in FM etc. But in order to prove something isn't right, you need to prove it. :) obviously...

[Wizard_03]

It doesn't mean it's 100% correct. There may be something incorrect, a bug in FM etc. But in order to prove something isn't right, you need to prove it. :) obviously...

 

+1 That’s my point, if you can share new data or back up claims of infidelity with solid numbers against real life documentation to the devs and sme’s then your wasting everyone’s time.

[Vitormouraa]

Yep.

 

Sorry when I said "in order to prove something isn't right, you need to prove it" I meant, in order to back up your claims you need to prove it with real documents, evidences and not just guesses and thinks.

 

Little mistake there. :D

[Auditor]

I see ZERO constructive comments in this thread.

 

Aluminium Donkey and Auditor, if you have something to show and tell then show and tell, shwow data and present something rather than just claims.

 

Auditor I already saw your report on R-13M missile which I checked and turns out missile behaving very much close to its IRL parameters, that is why I'm skeptic now.

 

If you really want stuff to be fixed stop useless arguing and argue base on data and documents.

 

"From the "digital stall" effect, to the lack of roll inertia" ok, good start you noticed something, then show it on scheme and why you think its wrong according to which source etc. otherwise it is useless thread which has no value for anyone..

 

Present your claims in academic fashion and you will get somewhere, otherwise nothing will happen..

Hello,

 

You can go into the thread where I reported the R-13's behavior and see the discrepancy from the Tacview files that mortisrose posted from its long-range behavior. Furthermore, your response that "R-13 information could be secret" is laughable. It's almost comical in nature that you would make such a claim and then proclaim that it's working as intended based on these secret documents of which you do not wish to share at this time of said 60-year-old missile.

 

Furthermore, your claims that the flight model is A-OK are directly contradicted by Leatherneck's old claim on their bugtracker and testing from players that show that there is indeed a problem with the flight model.

We're now to the stage where people aren't even denying it exists, but instead making excuses for why it's okay.

 

The fact that you would claim to be 'skeptical' because of top secret documents of which you refuse to show anyone else is ridiculous. I hope you understand that I'm not trying to be rude here; but I would say your post is the least meaningful in this entire thread and in my weapons performance thread.

 

Is that game/FM breaking? Hardly.

 

Keep things in perspective, please. Or will you explain to me that having 2G in stalls completely prevents the DCS Mig21 to be flown close to real in normal envelop and breaks the plane limitation that must be followed?

Sure: The reason people bring up the hard coded 2G behavior is because that's an edge case where you can see it affecting the flight model the most. It's proof that magic numbers went into the flight model to some extent, and this behavior does very much so affect all low-speed behavior, not just during a stall. Unfortunately, because we cannot actually see the game code or see the magic numbers or variables or flight modeling, we can't fly along at low-speed, simulating a dogfight, and just point to an instance where we hit max angular authority and say "SEE? SEE? THIS IS BECAUSE OF THAT 2G LIMIT" because during normal flight conditions; so many other variables play into the flight modeling as to make what contribution it has iffy. That's why the edge case is brought up: Because that's the point where it becomes extremely clear that this is not an organic flight model.

 

But, it does exist and it is affecting your low-speed performance. Whether you want to acknowledge it or not. If that's fine with you; sure, but that's on you isn't it?

 

 

Developers have stated the FM is Complete and verified by both them and ED..cased closed.

 

 

https://forums.eagle.ru/showthread.php?t=222266

 

I think the earlier posts in this thread sort of sums up my thoughts on it perfectly.

 

It's not PFM, never was intended to be PFM, in fact it's not even called PFM on the store page.

I'm still not giving up, because they have committed to contributing to the Mig-21. So who knows? Maybe we'll get that SAU stabilize feature we've been sorely needing.

Edited October 27, 2018 by Auditor

[Whisper]

Sure: The reason people bring up the hard coded 2G behavior is because that's an edge case where you can see it affecting the flight model the most. It's proof that magic numbers went into the flight model to some extent, and this behavior does very much so affect all low-speed behavior, not just during a stall. Unfortunately, because we cannot actually see the game code or see the magic numbers or variables or flight modeling, we can't fly along at low-speed, simulating a dogfight, and just point to an instance where we hit max angular authority and say "SEE? SEE? THIS IS BECAUSE OF THAT 2G LIMIT" because during normal flight conditions; so many other variables play into the flight modeling as to make what contribution it has iffy. That's why the edge case is brought up: Because that's the point where it becomes extremely clear that this is not an organic flight model.

 

But, it does exist and it is affecting your low-speed performance. Whether you want to acknowledge it or not. If that's fine with you; sure, but that's on you isn't it?

 

Errrr... What is your definition of "organic flight model" and "magic numbers" ?

Because it seems the only thing you seek is to prove that there are "magic numbers" in current Mig21 FM, and it's not an "organic FM", and that would be a bad thing.

AFAIK there is no magic "organic" FM possible on our current PC hardware that would simulate plane physics up to every flight envelop, there are "Magic Numbers" everywhere, in every FM, including ED PFM even though they push it as close to real as possible

The Mig21 FM is a EFM, ie, an AFM (with simulation/API not as advanced as ED's PFM) with added external calculations & simulations from third parties. Of course you will get "Magic Numbers" in there. The question is how much impact it has. And the only FM impact I see listed up to now is a weird behavior during stall. If these "magic numbers" were as bad as depicted, we would see other strange behaviors in other portions of the flight, that would make us fly wrong , during take off, combat maneuvers, etc...

The very fact we see a rather scripted behavior is not what indicates a broken model, it's rather normal, in fact. How far away this scripted behavior is from what I'm supposed to do as a virtual pilot, that is what is important to me. Hence why, as long as the only real impact on my flying is seeing a 2G load during stalls, I won't see the Mig21 FM as broken. If this 2G makes the stall handling by us pilot completely unreal, then yes things are more worriesome, but even that is not what I'm told is the issue....

[Frederf]

Chart says M1.0 to M2.0 at 13km,7500kg should take 380 seconds. In DCS I can do it in 206. Even with R-3S two missile configuration it is done in 225 seconds. Four missile config takes only 242 seconds.

 

Acceleration performance in this situation is 160-185% too great.

 

Минимальная приборная скорость полета обусдовлена началом сваливанмя ы составляет 290-230 км/ч в полетной конфигурацми, 260-190 км/ч в посадочной конфигурацым (массм и закрылки выпущены), в зависымосты от варжшнта лодвескж.

 

This is actually quite good. I was flying at 190 indicated in the landing configuration level. What I'm not so convinced about is what happens during the stall. Being on the backside of the CL curve by 0.1° seems to drop the lift off a cliff instead of being a symmetric function around the peak. Evaluation is hard because steady state stall plus a small angle AOA is difficult to maintain because control is lost.

 

Is the real airplane hard to hold at stall plus a small angle in terms of control? I don't know. Very little is said about post-stall behavior.

[Foka1]

Hello,

 

You can go into the thread where I reported the R-13's behavior and see the discrepancy from the Tacview files that mortisrose posted from its long-range behavior. Furthermore, your response that "R-13 information could be secret" is laughable. It's almost comical in nature that you would make such a claim and then proclaim that it's working as intended based on these secret documents of which you do not wish to share at this time of said 60-year-old missile.

 

Furthermore, your claims that the flight model is A-OK are directly contradicted by Leatherneck's old claim on their bugtracker and testing from players that show that there is indeed a problem with the flight model.

We're now to the stage where people aren't even denying it exists, but instead making excuses for why it's okay.

 

The fact that you would claim to be 'skeptical' because of top secret documents of which you refuse to show anyone else is ridiculous. I hope you understand that I'm not trying to be rude here; but I would say your post is the least meaningful in this entire thread and in my weapons performance thread.

 

First of all, rules of this forum forbid posting of tech documents, update yourself on that matter.

 

Second, I obtained missile chart from a former russian pilot, I still didn't get answer from him if its secret or not. Meanwhile though in Russia, some WW2 stuff is still considered secret, it is more bureaucracy thing that logic actually..

 

Third, I never said that MiG-21 model is "A-OK" I just said that no one can extract any start point for FM investigation from OP post here. Even without docs OP could have at least describe what is not working as intended and why he thinks that..

 

As for the missile, I just need to find a link somewhere in web to confirm that I can post at least that link, but no joy for now. Thing is R-13M thread started with no documental support, so even if I claim something and you say its laughable, same "laughable" degree can be used to initial claim there. So we are equal. Thing is though max speed of R-13M is 550 meters per second, you can see on my charts which are same tacview charts as Mortisrose posted you can see that R-13M reached 2457 km per hour. So your initial claim "The R-3R and the R-13 can barely cross mach 1.6 before burning out" already not checking out. That was my main point, and "sikrit dokumints" is secondary.

 

PS I don't believe that you are not trying to be rude ;) sorry if I offended you somehow.

[SpeedStick]

All I know is that it's a bit rediculess that SAU problem hasen't been fixed yet.

This was my favourite module, but since the split...meh.

[hovring]

All I know is that it's a bit rediculess that SAU problem hasen't been fixed yet.

This was my favourite module, but since the split...meh.

 

 

yeah, sad but true. A lot of promise, and the rest... well time will be the judge I guess. Over 4 years in "early accses"..... and now the lighting in the cockpit is broken, missiles i s wonky, SAU wierd... yeah, still hoping though...

Or Heatblur makes a J-35......