About stall in Version 1.5.6.3930.271

[chn6]

Version:1.5.6.3930.271

 

I feel MiG-21Bis into stall is too balanced, Although I did not personally drive MiG-21Bis, but I have here J-7 is the Chinese version of MiG-21 manual, Although China's J-7 and MiG-21Bis are different, but I believe that the aerodynamic layout and no significant difference they should have a similar performance.

 

J-7 manual written:

 

"1. flat fly stall

If the aircraft to maintain the conditions of the slowdown in the flight, then, as the flight speed gradually reduced, the aircraft's angle of attack to gradually increase.

 

J-7 aircraft flaps, landing gear in the collection position, flight height 10000 ~ 13000 meters, gradually close the throttle, the soft back to maintain the flat rod, when the IAS reduced to 310-290 km/h, the aircraft There is a slight jitter and shaking left and right, indicating that the aircraft reached the level of flying speed. Continue to reduce the speed, the aircraft jitter intensity did not increase significantly.

 

The IAS reduced to 260 km/h, the aircraft began to tilt the trend, then with ailerons and rudder can still eliminate the tilt. When the IAS is reduced to 220 to 210 km/h, the aircraft tilt has been unable to control, in the rudder and aileron in a neutral position, the aircraft appears unstable, the wing to the side of the fall, while the nose sink The This shows that the aircraft has been slowed down to the speed of the flight. If the forward putter at this time, the aircraft will be a smaller angle of attack into the subduction speed, return to normal operation. But if the rudder at this time, the aircraft will be on the side of the rudder into the spiral. "

 

Please note that the red text part is where our current simulation does not come out: While the MiG-21Bis in the stall, almost can not occur unilateral wing sinking situation, and there is no left and right swing occurred.

 

 

Another problem is MiG-21Bis has lost a very good simulation feature: the swing roll at high angle of attack.

 

We all know that when the stall, the flow separation on the surface of both sides of the wing may not be completely consistent, so the aircraft will change due to the large slope, and sweep delta wing aerodynamic characteristics, MiG-21Bis will swing roll. The previous version has been very good, but why now canceled it?

 

J-7 manual written:

 

"2. Stall in other flight conditions

In the sub-sonic hover, such as the drawbars too much, J-7 aircraft will appear jitter, left and right swing and pitching phenomenon. If the rod may enter the spiral.If the aircraft metamorphosis moment, forward putter and kick to eliminate skid, The plane will stop jitter and enter the subduction."

Now, we lost left and right swing when MiG-21Bis Stall with High angle of attack.

 

The stall in the previous version of the swing is a very realistic performance, but should not have a very fast roll.

 

Edited April 8, 2017 by chn6

[Golo]

I see it the same. In fact I have been saying that since version 1.3 or so when it got lost from FM.

It is definitely too stable in roll at slow speed/high AOA, there should be sometimes as much as +- 50deg of wing rocking at 200km/h as described in manual.

[CCCP_gd]

I hope the new team do it as fly manual.that we can fly the most real mig21 on our computer！

[inSky_1911CFZS]

Totally agree.

[Sporg]

I have not tested the new FM so much, but maybe it would be better to compare with the actual MiG-21bis manual that has been publicised earlier?

 

 

 

It's from "MiG-21Bis_Pilots_Flight_Operating_Instruction.pdf".

A little difficult to find a good link to now, but try to Google it.

 

Note that it talks about very big almost symmetric oscillations when nearing a stall.

And it also mentions the tendency to pitch down at landing.

 

Anyway I trust LN will make it fine, having a real MiG-21 pilot amongst them.

Edited August 4, 2017 by Sporg
Had to remove Photobucket's begging for money.. :(

[chn6]

Great，I forgot is PDF，thank you！