Elevator and ailerons getting stuck during landing.

[marcin34-13]

After update on 24th of december 2021 during landing elevator or ailerons are getting stuck. So, I am on final in accordance to original MIG-21bis flight manual, speed 450km/h flaps t/o, reducing speed to 420km/h, flaps landing and woopsie, we've got no ailerons nor elevator. In Real flight manual there is nothing about that this event may occur. Some other people reported also loss of hydraulic pressure. If someone interested here is the link to original MiG-21bis flight manual, but in polish language. https://www.muzeumlotnictwa.pl/index.php/digitalizacja/katalog/1363

Edit: Here's english version of flight manual: https://drive.google.com/file/d/1YFYiihLhiVT1_ugmI8rBuJllueNR8ewG/view?usp=sharing

Edited December 26, 2021 by marcin34-13

[MiG21bisFishbedL]

I've been doing some slow flight, playing around with the flaps to see what happens.

@ ~350kmh indicated, there's no issue, at all. I just did a few laps around Batumi in that configuration. Both with TO and LDG settings. Altitudes were between 1000 and 600m as I saw a lot of altitude fluctuation, but basically pattern altitudes.

I increased airspeed to ~400kmh indicated and still the same results.

However, once you break that 450kmh mark? That's when the witchcraft happens. At around 430 indicated, at full flaps, you do get hydraulic pressure warning, but it soldiers on. Past 450 and flight controls do, indeed, lock up. It's as if the system disconnects your controls; stick's a movin', but there's no visible control input externally and no way to correct this in a way to return any semblance of control outside of throttle input. Even that sees the RPM jumping around like a jackrabbit. Not sure if that's accurate to the Tumansky's performance.

I can post a track later. For now, extend those downwind legs and give yourself plenty of space to slow down on approach. Probably want to drop the gear as soon as you get under that 600kmh indicated max extension threshold.

Edited December 26, 2021 by MiG21bisFishbedL

[marcin34-13]

I just learn to fly from original real life flight manuals, and original flight manuals don't say anything about it. As far I know dcs is for realistic simulations, so the real life flight manuals should be the best. I've got about 150hours of flight, and another 100hours from training. Limitations also didn't mentions anything about it.

Edited December 26, 2021 by marcin34-13

[MiG21bisFishbedL]

3 minutes ago, marcin34-13 said:

I just learn to fly from original real life flight manuals, and original flight manuals don't say anything about it. As far I know dcs is for realistic simulations, so the real life flight manuals should be the best.

It's not a bad starting position. I'm trying to find if this behavior is realistic, period. If it is, I suspect it's engaging incorrectly. I'd imagine it'd be engaging at a higher speed.

Edited December 26, 2021 by MiG21bisFishbedL

[609_Relentov]

OK cool, so I'm not going crazy.  I was seeing the same thing yesterday (on long final, seemingly frozen elevator/horizontal stabilizers, and nosing into the ground), but I think my problem was I deployed my landing flaps and got too slow too early on my approach.  Seems to be working better to only deploy take off flaps first - what worked for me (approximate speeds):

On descent, keep speed above 500kmh
- Long final, drop to 500kmh, lower gear, maintain at least 400kmh
- Medium final, lower take off flaps, maintain at least 350-400kmh
- Short final, lower landing flaps, maintain 300-350kmh, 10 degrees AoA

[xnomad]

I just learned about this 'change' the hard way. I just flew a long campaign mission, coming into land, everything locks up and nosed down into the dirt.
I'm going to fly that whole mission again, but will practice landing first.

[marcin34-13]

Edit: Not a bug it is a "feature", guys with this patch broke down the plane. Real MiG-21bis doesn't work that way. Topic Closed.

 

EDIT2: Fresh news from programmers: "The story with hydraulic system and engine sound is a bug. Will be fixed in latest patch. Dirty canopy also will be cleaned, but later." Topic Definitely Closed.

Edited December 29, 2021 by marcin34-13

[MiG21bisFishbedL]

2 hours ago, marcin34-13 said:

 Real MiG-21bis doesn't work that way. 

 

 

Sourcing? I'm honestly scouring over my resources to find anything on this kind of inflight failure.

[rossmum]

I don't see anything in the flight manual that suggests it's correct behaviour, nor does it make much sense to lose all control authority with how the hydraulic system operates.

[MiG21bisFishbedL]

4 hours ago, rossmum said:

I don't see anything in the flight manual that suggests it's correct behaviour, nor does it make much sense to lose all control authority with how the hydraulic system operates.

I was thinking the same.