MiG-29 G load

[AeriaGloria]

Hello, it seems to be that MiG-29 can not reach the stated instantaneous G load, and it is low enough that it also can’t reach the full envelope of the sustained turn rate numbers. 
 

Here is a track with 2x APU-470, and 2x R-60, and 50-55% fuel in order to reach 13,000 kg gross weight, which seems to be the most common testing metric other then the same with 2x R-73. 
 

in addition there is a max G load graph we see in both books and manuals that goes from below 300 kmh to 900 kmh, showing over 20 deg/s at 900 kmh “with missiles.” And there is a sentence in the “practical aerodynamics” manual that states:

“For example, the maximum speed of turn in a steady position of the aircraft without weapon mounts at an altitude of 1,000m, Mach Number 0.8, with 50% of remaining fuel (aircraft weight 13,000 kg) is 19.5-20° a second.”

Partway through the track I also jettison the R-60 to show a “without missile load” configuration. 
 

Images are from Yefim Gordon or GAF TO-1 from Amazon. According to instantaneous turn chart, we should approximately have little issue hitting 9 G at lower altitudes from around Mach 0.55-0.85, or around 700-1000 kmh at lower altitudes. And above this speed the transonic zone is reducing elevator authority until around Mach 1.05-1.1 (according to practical aerodynamics.) Instead, we are limited to basically 8 G from below 900 kmh, which should be our maximum rate 9 G speed. 

 

MiG29gload.trk

Edited Sunday at 05:29 AM by AeriaGloria

[Lixma 06]

Sustained turn rates I'm seeing @ 1000m, 20°C

13000kg fuel, no pylons - 20°sec @900kp/h

13000kg fuel, 2 x R-73 - 19°sec @900kp/h

13000kg fuel, 2 x R-27R, 4 x R-73, Ext. Fuel - 16°sec @ 900kp/h

 

[AeriaGloria]

This is also about instantaneous turn. It should have no issue hitting 9 G at low alt from Mach 0.55-85. Mach 0.65-0.85 at 3 km. 
 

In addition the instantaneous chart and the two sustained turn charts show that it can reach 9 G at 900 kmh (20 deg/s) with atleast up to 2x Archer loaded. Doing that sustained, the instantaneous chart shows it should have some pull in reserve (not needing full back stick as it does now)

Edited Sunday at 07:43 PM by AeriaGloria

[sylkhan]

This confirms my tests.
I have done numerous online tests (dogfighters servers), and it turns out that the Mig-29 is the worst dogfighter.
At speeds < 800/850 km, the Mig-29 turns really badly, and performance is poor, with a lot of drag.
The F-18, F-16, F-15, and M2k, JF-17 all outperform the Mig-29, even the F-14 turns better at low/medium speeds, lol.
I win all the time vs Mig-29, i Lost all the time vs other fighters.
Is the real Mig-29 really that bad?

Edited Monday at 06:04 PM by sylkhan

[AeriaGloria]

35 minutes ago, sylkhan said:

This confirms my tests.
I have done numerous online tests (dogfighters servers), and it turns out that the Mig-29 is the worst dogfighter.
At speeds < 800/850 km, the Mig-29 turns really badly, and performance is poor, with a lot of drag.
The F-18, F-16, F-15, and M2k, JF-17 all outperform the Mig-29, even the F-14 turns better at low/medium speeds, lol.
I win all the time vs Mig-29, i Lost all the time vs other fighters.
Is the real Mig-29 really that bad?

As we see from the charts I attached, sustained and instantaneous, it shouldn’t be

[AeriaGloria]

With more testing here is what I can tell. 

At 0m, it matches charts well 

At 3 and 5 km, it also matches charts well 

However, the main issue is something we don’t exactly have charts for, which is the region from above 0-2 km, more specifically around 0.5-2 km. 
 

I think one thing going on here is that ARU begins is at its smallest amount of deflection from 870-1200 kmh between 0-2 km. Above 2 km, it begins to increase deflection again. 
 

At 0 km, it is just enough authority to match the charts well. However once we raise altitude between 0 and 2 km, the authority is not enough the slightly thinner air. 
 

What surprises me most is how big the difference is, at 0 m it has little issue often pulling more then 10 G, and hitting 9 G over a significant range. 
 

At say 1-2 km, it will almost never go over 9 G, hitting 9 G at a very narrow range of speeds (920-940 kmh) if that, and often being limited to 8-8.5 G or less at 1-2 km between 870 kmh and Mach 0.85. 
 

The instantaneous G chart indicates it has no problem hitting 9 G at 0 km from 0.55-0.85 M, at 3 km at 0.65-0.85 M, and 0.75-0.85 M at 5 km, which gives the impression it should atleast have no problem hitting 9 G at say 0.5-2 km from perhaps 0.6-0.85 Mach, which is not the case in game. 
 

I am very surprised if 500-2000m is enough to make that much of a difference. 
 

 

[AeriaGloria]

Okay here I focused on a slightly different aspect, the dip in G shown by the instantaneous chart at 0.85-1.1 Mach.
 

This track should show whether at 0 km, 3 km, or 5 km, it is pulling too much G at Mach 0.85-1.1. I know that tuning a FM is often a “balance,” and that this may have to do with it often barely or not even pulling 9 G instantaneous at say 0.8-0.85 G at lower altitudes such as 1000-2000m which I demonstrated with the first track. 
 

In the “MiG-299G” track I instead tried to focus on the speeds it can hit 9 G from 0-3000m. Knowing per the chart it should hit 9 G at 0m from 0.55-0.85 Mach and 0.65-0.85 Mach at 3 km, I would say that the window it hits 9 G is just too narrow. 
 

Instead of hitting 9 G at Mach 0.85 or right around it, I would routinely have a huge jump to 9 G and over at around 0.8 Mach. It would then stay at 9G or over until perhaps about 0.05 Mach above where the chart said it would maintain it. 
 

So overall I would say it hits 9 G at too narrow of a speed below 0.85 Mach, and can hit too high of a G from 0.85-1.1 Mach. 
 

Granted, the behavior is much more accurate and superior then it was before the FM was adjusted for FF release (which debuted with the FC3 module the patch before the MiG-29 FF release), I just think it needs a little extra touch to reach the DCS standard. 

MiG-29goverload2.trk MiG-299G.trk

[sylkhan]

@AeriaGloria

I have done some tests on sustained turn rate.
Clean, Alt 500m, 13000 kg
mach 0.55, 378 knots, 700 kmh, 6.5G SHOULD BE 7G (your chart "sustained G turn capability, max AB")
mach 0.6, 400 knots, 740 kmh, 7G SHOULD BE 7.5G (your chart "sustained G turn capability, max AB")
mach 0.63, 420 knots, 780 Kmh, 7.2G SHOULD BE 8G (your chart "sustained G turn capability, max AB")
mach 0.68, 453 knots, 840 kmh, 8G SHOULD BE 9G (your chart "sustained G turn capability, max AB")

There is a big difference !
Can you confirm.
Thx

Edited 7 hours ago by sylkhan

[Pavlin_33]

When it comes to instantaneus turns, they are just G limited turns until you reach a certain speed after which the frame can't sustain max G. One thing to notice is that max AoA decreases with the increase in Mach number.

If you can't reach max G above corner speed that means that either AoA limit was exceeded or the elevator does not have enough authority or is somehow limited.

[AeriaGloria]

6 hours ago, sylkhan said:

@AeriaGloria

I have done some tests on sustained turn rate.
Clean, Alt 500m, 13000 kg
mach 0.55, 378 knots, 700 kmh, 6.5G SHOULD BE 7G (your chart "sustained G turn capability, max AB")
mach 0.6, 400 knots, 740 kmh, 7G SHOULD BE 7.5G (your chart "sustained G turn capability, max AB")
mach 0.63, 420 knots, 780 Kmh, 7.2G SHOULD BE 8G (your chart "sustained G turn capability, max AB")
mach 0.68, 453 knots, 840 kmh, 8G SHOULD BE 9G (your chart "sustained G turn capability, max AB")

There is a big difference !
Can you confirm.
Thx

I am not terribly surprised, though I am not so good at testing sustained rate vs instaneous. I will say from my testing your results sound on the money of about 0.5 G difference. I will see if I can definitively test it. My only question for you is where you got 500m as the charts seem to usually go 0m/3 km/5km. 

 

4 hours ago, Pavlin_33 said:

When it comes to instantaneus turns, they are just G limited turns until you reach a certain speed after which the frame can't sustain max G. One thing to notice is that max AoA decreases with the increase in Mach number.

If you can't reach max G above corner speed that means that either AoA limit was exceeded or the elevator does not have enough authority or is somehow limited.

It should atleast come pretty close to the chart no? We are not coming close to AOA limiter here. According to “practical aerodynamics (MiG-29)” the G behavior we see here Where it pulls 9 G below Mach 0.85, then G decreases significantly to Mach 1-1.2 and then increases, is entirely due to the center of pressure moving back from transonic effects and the elevator losing efficiency/leverage as the airframe becomes more stable essentially. 

Edited 1 hour ago by AeriaGloria

[sylkhan]

36 minutes ago, AeriaGloria said:

I will say from my testing your results sound on the money of about 0.5 G difference.

0.5G to 1G, that's big.
 

 

39 minutes ago, AeriaGloria said:

My only question for you is where you got 500m as the charts seem to usually go 0m/3 km/5km. 

Ah, 0 was too low :), then i took 500m to do my tests without crashing on the ground, it was arbitrary.

[AeriaGloria]

I’ll try and do your test at 100m.