38Deg AoA Wobble at 600+kph IAS. Thoughts ? - Page 3 - ED Forums
 


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Old 03-27-2020, 05:12 AM   #21
Cgjunk2
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I took up the mig to check on the accelerated stall characteristics at higher airspeed. Most of the time at speeds above 900 i could not reach 38 degrees AoA and stall before blacking out or bleeding speed low enough, which is what I would have expected. So in my opinion, the acc stall behavior seems realistic on theoretical grounds. In real life, manufacturers guarantee you a maneuvering speed below which an accelerated stall will always happen under high AoA. But if you maneuver above that speed, the wing will continue to fly with as much wing load as you put on it including until the point of complete structural failure (or human failure). Of course, modern fighter jets eliminate structural failure possibility by digitally limiting the amount of AoA/ G’s that you can pull.

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Old 03-27-2020, 09:50 AM   #22
Golo
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Originally Posted by ataribaby View Post
It is basically beyond to be useable and to be fun. Every take-off landing is big gamble now.

You are overreacting a big way, I was able to takeoff just fine within parameters described in pilot manual and landing was absolutely fine,

direction control was no problem with a little crosswind and my VS during touchdown was less than 1m/s at about 300km/h, so very controlable, didnt even had to use chute.


This was great update to MiG-21 (appart from that 38° AOA problem), it feels lively if somewhat under powered.
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Old 03-27-2020, 11:11 AM   #23
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As I've said, FM is going to see more tuning so we will work on all this issues guys!
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Old 03-27-2020, 07:23 PM   #24
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Originally Posted by TLTeo View Post
That is very interesting and counter intuitive. In my mind, loss of aileron authority just kind of always happens. It could be that in the mig-21 it somehow occurs at speeds lower than a reasonable stall speed, hence the behaviour we're seeing.
NOT AN ENGINEER but from what I understand, there are ways to mitigate it through design and certain aircraft do retain usable roll authority even well into the stall. That said, I don't think the 21 has any of the usual design features that cause this, and it also lacks roll from the stabs (as correctly modelled visually, and as far as I can tell reflected in the FM - I think old problems of retaining roll auth without ailerons was a DM problem where it thought they were still there).

Thankfully, whether it's accurate or still needs tweaking, it shouldn't really make too big an impact on gameplay as putting yourself into that state during a fight is 100% going to result in death, you're a standing target and will take forever to regain your speed.

As for T/O and landing... landing doesn't feel much different to me other than the aircraft is slightly more prone to wandering. The bounce induced by the suspension stiffness is what's messing with me most, including for T/O. I fly by feel and not any manuals, so maybe doing a by-the-book landing is complicated now, but my usual standby of coming in at 380-400 and then dropping to 280-320 over the fence hasn't been causing any issues at all.
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Old 04-02-2020, 05:07 AM   #25
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Anyone think some of this behavior is tip stalls and single wing wings stalls which also causes huge adverse yaw? I remember it always used to stall both wigs at the time if you pulled, but no it tip stalls with enough encouragement. Am I imagining this? Sure it might need to betuned, but I really like it
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Old 04-02-2020, 10:08 PM   #26
Cgjunk2
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As far as I'm concerned the behavior the OP posted about is what you would call a tip stall, or put another way, one wing stalling slightly earlier than another. I seem to recall the previous FM would break cleanly and straight ahead IRC. The new stalling behavior seems believable to me, but I have no idea if the real Mig21 stalls straight ahead or not.
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Old 04-03-2020, 12:20 AM   #27
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I don't know why you expect anything other than an accelerated stall when hitting 38 degrees AOA.
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Old 04-03-2020, 01:05 AM   #28
Cgjunk2
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Quote:
Originally Posted by rinkerbuck View Post
I don't know why you expect anything other than an accelerated stall when hitting 38 degrees AOA.
Who, me? The original poster described this as a “wobble” and “snap to horizontal” that the OP said felt wrong and scripted. Based on the words used, I am not sure if the OP understood this to simply be a stall. When I flew according to the OPs speeds, I got the same behavior and interpreted it to be an accelerated stall, as opposed to a problem with the FM.
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