Turn rate re-tested

The turn rate of the Mirage at SL remains an abysmal low 7 G's sustained @ Mach 0.9 at 55% fuel completely clean.

Infact in many cases I was unable to sustain over 6.6 G's at Mach 0.9 at SL.

This is far short of the 9+ G's the real aircraft will easily sustain at sea level in a 2x Magic loaded configuration.

I have same expirence...

The charts given in the manual give a maximum of about 8.5G @ M0.9 at sea level. Much more than 6.6G, but far from the "(easily) 9+" you mention. And that is for a clean aircraft.

Just asking what is your source ? It may be there are several sources out there that don't necessarily agree with one another.

The charts given in the manual give a maximum of about 8.5G @ M0.9 at sea level. Much more than 6.6G, but far from the "(easily) 9+" you mention. And that is for a clean aircraft.

 

Just asking what is your source ? It may be there are several sources out there that don't necessarily agree with one another.

If the manual states 8.5G then why can the DCS:2000C only fly ~7G?

I'm asking out of curiocity how do you perform these tests?

The charts given in the manual give a maximum of about 8.5G @ M0.9 at sea level. Much more than 6.6G, but far from the "(easily) 9+" you mention. And that is for a clean aircraft.

 

Just asking what is your source ? It may be there are several sources out there that don't necessarily agree with one another.

My source is estimates by aeronautics experts Glenn Ball & Pawlovksi:

This is for 15,000 ft, 6.7 G sustained, which easily translates into 9+ Gs at SL:

I'd consider the above more or less official and probably even conservative based on their F-16A estimates.

I'm asking out of curiocity how do you perform these tests?

Simple, I fly down to SL attaining a speed of Mach 0.9 and then commence a constant rate turn whilst maintaining altitude, I then determine the speed at which I can maintain a certain load factor.

Example:

In all cases so far I have been unable to maintain a speed of Mach 0.9 whilst maintaining a load factor of more than ~6.7 G's. Pulling any G above this at Mach 0.9 whilst maintaining altitude (~50-100m) results in a loss of speed, exactly the same as before the patch. Pulling 9 G's at Mach 0.9 results in a rapid loss of speed, this should no happen, infact at Mach 0.9 @ SL the aircraft should continue wanting to accelerate whilst pulling 9 G's, same as the F-15 currently does.

If the manual states 8.5G then why can the DCS:2000C only fly ~7G?

Perhaps because the flight model is still WIP, or RAZBAM are not basing it exclusively on these charts.

I'm asking out of curiocity how do you perform these tests?

Go to your test altitude, around your desired Mach number, then begin a turn (trying to keep the same altitude) at max afterburner. You have to adjust you angle of bank and pull to stay level with a constant speed. If you're losing speed, release the stick forward a bit, if you're gaining speed, pull a little more, all the while checking your altitude or rate of climb to stay level.

When you have managed to keep a constant speed at a constant altitude, you will be in a sustained turn. Check your G-indicator, now, it should be stable and will indicates your sustained G.

Note that you can deduce turn rate from G and True Airspeed (or Tacview can show it to you).

My source is estimates by Glenn Ball & Pawlovksi:

 

This is for 15,000 ft, 6.7 G sustained, which easily translates into 9+ Gs at SL:

 

Ok, so yet again you are extrapolating sea level performance from a 15 000 ft chart? Why in the world would you not simply make your tests at 15 000 ft? Even if it may be slightly harder to do (would it really?), it would be a sound basis for comparison.

BTW, the manual charts for 15 000 ft give only about 5.8 G, for 10.6 tons vs 9.5 admittedly, but without Magics I think (Drag Index = 0). Do they agree, and if not which is more correct, I cannot tell.

Ok, so yet again you are extrapolating sea level performance from a 15 000 ft chart? Why in the world would you not simply make your tests at 15 000 ft? Even if it may be slightly harder to do (would it really?), it would be a sound basis for comparison.

Do you understand how altitude effects lift?

Knowing the engine performance from 0-15,000 ft extrapolating SL performance is as easy as 1-2-3.

Just tested the max sustainable load factor at 15,000 ft @ Mach 0.9 clean 55% fuel = ~4.5 G's. (just as expected)

2+ G's short of the 6.7 G's on the Fighter Symposium chart.

Just tested the max sustainable load factor at 15,000 ft @ Mach 0.9 clean 55% fuel = ~4.5 G's. (just as expected)

 

2+ G's short of the 6.7 G's on the Fighter Symposium chart.

That's interesting.... I'll try to verify your results if I can hummingbird. Two independent tests better than one right?

That's interesting.... I'll try to verify your results if I can hummingbird. Two independent tests better than one right?

Of course :)

Does the chart say what engine was used? Which version of the 2000?

 

BTW, the manual charts for 15 000 ft give only about 5.8 G, for 10.6 tons vs 9.5 admittedly, but without Magics I think (Drag Index = 0). Do they agree, and if not which is more correct, I cannot tell.

I personally have a lot more faith in the estimates of actual aeronautic experts than the charts from a video game (The charts in the manual are from BMS). Ball & Pawlovski's charts were by comparison made on demand for military purposes.

Looking at the Mirage 2000's specs it would also make very little sense if was only 5.8 G's a 15,000 ft, almost a full 1 G short of professional estimates (which are likely conservative btw).

Keep in mind that the Mirage features a wing loading over 100 kg/sq.m. lower than that of the F-15, whilst at the same same featuring large LE devices. There's no way it would perform worse in the turn than the F-15.

6.7 to 7 G's sustained at 15,000 ft is a lot more reasonable, esp. in clean configuration where it should be able to sustain 7 G's at 15 kft. It's rather hilarious that it needs to drop down to SL to even achieve that atm.

I really hope RAZBAM are working on it.

Does the chart say what engine was used? Which version of the 2000?

Yes, it lists the SNECMA M-53P-2 engine and a max thrust of 22,046 lbs at SL.

Yes, it lists the SNECMA M-53P-2 engine and a max thrust of 22,046 lbs at SL.

Does that match the engine modeled in DCS? RAZBAM wrote 21400lbf (95.1 kn) in the manual.

Other parameters are different as well. Could it be RAZBAM modeled something different than the chart?

Does that match the engine modeled in DCS? RAZBAM wrote 21400lbf (95.1 kn) in the manual.

Other parameters are different as well. Could it be RAZBAM modeled something different than the chart?

RAZBAM didn't write it though, some other third party dev for BMS Falcon did.

A difference of 3 kN shouldn't make any noticable difference, esp. if the weight is higher by a similar amount as well.

RAZBAM wrote the DCS manual is what I was referring to and I was comparing the numbers in the manual with the numbers in the chart. If the chart is using an updated mirage 2000C, which I can't tell or if RAZABAM modeled and different version, it could be part of the problems beside the fact that the DCS Mirage 2000C is not finish.

I personally have a lot more faith in the estimates of actual aeronautic experts than the charts from a video game (The charts in the manual are from BMS). Ball & Pawlovski's charts were by comparison made on demand for military purposes.

Gentlemen lets not start this fight again, why do you think the charts disappeared from manual ? :music_whistling:

1- BMS isn't more a video game than DCS.

2- the guy who did these charts has more than serious aeronautical background.

3- some former Mirage crew are flying BMS.

4- each simulator has its own limitations.

So these charts are likely an inspiration, you can't copy/ paste FM from BMS or FSX into DCS.

What matters the most in my sense is to get the general behavior.

Gentlemen lets not start this fight again, why do you think the charts disappeared from manual ? :music_whistling:

 

1- BMS isn't more a video game than DCS.

2- the guy who did these charts has more than serious aeronautical background.

3- some former Mirage crew are flying BMS.

4- each simulator has its own limitations.

 

So these charts are likely an inspiration, you can't copy/ paste FM from BMS or FSX into DCS.

 

What matters the most in my sense is to get the general behavior.

Being 2+ G's short at most alts is not really capturing the general behavior though :P

But I'm sure RAZBAM are working on it.

Of course it's WIP...

This is far short of the 9+ G's the real aircraft will easily sustain at sea level in a 2x Magic loaded configuration.

A side question is whether any pilot can "easily sustain" 9+ G's. Won't be for long anyway. An F-16 pilot can pull a 9G turn, but that doesn't mean he will be circling around at 9G.

The turn rate of the Mirage at SL remains an abysmal low 7 G's sustained @ Mach 0.9 at 55% fuel completely clean.

 

Infact in many cases I was unable to sustain over 6.6 G's at Mach 0.9 at SL.

 

This is far short of the 9+ G's the real aircraft will easily sustain at sea level in a 2x Magic loaded configuration.

Did you try in 2.0?

I'm pretty sure Hummingbird did his testing in 2.0, as he says he has "re-tested" the turn rate and it is "still" wrong.

Just tested the max sustainable load factor at 15,000 ft @ Mach 0.9 clean 55% fuel = ~4.5 G's. (just as expected)

 

2+ G's short of the 6.7 G's on the Fighter Symposium chart.

Hmm, this seems way off, not only of the Fighter symposium chart, but of the BMS one as well, which says about 5.8 G with a heavier aircraft.

Obviously the FM is still very much WIP. I cannot test myself because I do not have 2.0, so I could only test the older 1.5 behaviour.

I also noticed that the Mirage vs F-16 comparison you gave (hadn't seen them anywhere, thank you!) give a rather lower turn rate than the Fighter symposium chart in what seems to be roughly the same conditions (11°/s sustained vs 12.5°/s) ; internal fuel is not given though.

Once again, I am not assuming anything on the trustworthiness of various sources, I am trying to look at every available source before making an opinion, since we do not have official Dassault or Armée de l'Air sanctionned charts (or from any country that operates the Mirage 2000C).

I still think it is easier for everybody if we strive to tests the charts in the same conditions they show (loadout, fuel, altitude, atmospheric conditions, etc...).