MiG-15 and F-85 Sabre Issues (post them here)

RATE OF CLIMB (ROC)
Here is the real world data (RWD) ROC data
[Image: RWD_MIG15BIS_ROC.png]
NOTE the ROC @ SL is 50m/s (9843fpm).

Here is the ingame raw ROC data
[Image: ROC_VS_ALT.png]
NOTE the ROC has spikes and varies with elevator adjustments, just as it did in real life, the next step is to plot a best fit line threw these data points, knowing in advance the large spike near SL is due to the aircraft not settled in on the best climb speed, that is to say not valid data, thus the need to do a best fit line threw the data.

Here is the best fit threw the ingame ROC data
[Image: BF_ROC_VS_ALT.png]
NOTE the ROC @ SL is 59m/s (11,614fpm) a full 9m/s (1,772fpm) greater/better than the RWD ROC, 18% error.

TIME TO CLIMB (TTC)
Here is the RWD TTC data
[Image: RWD_MIG15BIS_TTC.png]
NOTE the TTC @ 10km is 5min

Here is the ingame raw TTC data
[Image: TIME_VS_ALT.png]
NOTE the TTC @ 10km is 4.37min a full 0.63min (37.8sec) quicker/better than the RWD TTC, 12.6% error.

SUMMARY
All testing was done on the '[MOD] Flight Test Map - ISA' i.e.

viewtopic.php?t=13988

Purpose being it is a standard atmosphere map (STD) and therefore allows direct comparisons to RWD in STD format.

The testing of the MiG15biss shows the ROC to be 'better' than a real world MiG15biss at all altitudes, which results in better time to climb values at all altitudes.

NOTE the ROC test result @ SL shows 59m/s where as the IL2C data shows ~64m/s. I belive this is due to me performing the test using the RWD best climb speeds (BCS), i.e.

Here is the RWD BCS in IAS
[Image: RWD_MIG15BIS_BCS_IAS.png]

Here is the ingame raw BCS data
[Image: IAS_VS_ALT.png]

I feel confident that if I ignore the real world BCS and find the ingame BCS that I will be able to obtain the ~64m/s shown in IL2C, in that data is not restricted to flying at real world BCS values, it uses the ingame BCS values.

All in all it should be clear to all that the current MiG15biss FM needs to be toned down a bit to better simulate its real world counterpart.

EXTRAS
Track File of ROC test (note you will need the '[MOD] Flight Test Map - ISA' installed to run it
http://www.flightsimtesting.com/fst/il2 ... ADJBCS.zip

Suport data
[Image: RWD_ROC_VS_ALT.png]
[Image: X_VS_Y.png]
[Image: TIME_VS_IAS_AND_TAS.png]
[Image: TIME_VS_TAS_ACC.png]
[Image: TIME_VS_PITCH_AND_AOA.png]
[Image: TIME_VS_JS_THROTTLE.png]
[Image: TIME_VS_RPM.png]
[Image: TIME_VS_OIL_TEMP.png]
[Image: TIME_VS_KE_PE_TE.png]
Reply

Well done! So the main discrepancy we have is "automatic rocket boosters" that works from ground to 2000m.
BTW have you tested constant turn on 1000m?
Reply

Sneeke Wrote:Well done! So the main discrepancy we have is "automatic rocket boosters" that works from ground to 2000m.
LOL! Nah that is just my suckie flying tryin to stabilise on the BCS.

Sneeke Wrote:BTW have you tested constant turn on 1000m?
No, but I figure if I can redo this test such that I can use the ingame BCS and obtain the 64m/s ROC, than I just assume the IL2C turn times are also valid at 1,000m
Reply

Damn... I really missed your charts Tagert, but I swear I never thought they'd be in this post :lol:

That being said, thanks a lot for taking the time to do them Smile
Reply

PeterD Wrote:Damn... I really missed your charts Tagert, but I swear I never thought they'd be in this post :lol:

That being said, thanks a lot for taking the time to do them Smile
No Thank You!

This whole Korean theme you and Flakiten have done has really energized a lot of folks.. Granted Korean Jet war guys like me and the others is a nitch group in the all ready nitch group of IL2, but everyone I have talked to and flow with have not been this excited in a really long time!

PS As soon as I can find some good data on the F86 Ill do a test on it too, Finding late F86F data is easy, but finding early F86A stuff is hard. I ordered the F86A flight manual, should be here this week, so maybe next week some time!

Anyway.. Thanks again for the great mods!
Reply

Hey PeterD!

I was wondering, if you are keeping a running list of bugs..

If so, could you post them here from time to time, or update your first post with the total list?

And, in that list could you list which ones have been addressed/fixxed and those that are still pending?

It would help folks determine if what they are seeing is a bug, and if it has been reported yet, and if it is fixed for the next update, or if it is still and issue they will have to deal with

Just a thought!

S!
Reply

I encountered 2 FM problems.The first is ground handling, both 2 planes cannot turn into the runway within the limitation of the taxiway at 15km/h,though I applied full rudder and applied break. They just refuse to turn and always get out of the taxiway.

The second one happens during takeoff on both aircrafts,especially the MiG-15/17,100% RPM,takeoff flaps,no trim,full tank,and when I pull back the stick to rotate at a speed below 200km/h,the aircraft never responses,and the nosewheel never lifts,when the speed reach 200km/h,at that exact moment ,even without any control input,the plane suddenly lifts its nose and bounce into the airautomaticly.If I pull the stick at that point,the plane stalls(sudden drop of wingtips).

BTW,what are the proper ROTATE/APPROACH/TOUCHDOWN speed of yours? I flew the bearstudio MiG-15/17 and SectionF8 in FS,but they are totally different.

Could you guys help me? Thanks in advance.
Reply

Both aircraft are great but why doesn't the MIG have any lights at all :?:
Reply

fallout3 Wrote:I encountered 2 FM problems.The first is ground handling, both 2 planes cannot turn into the runway within the limitation of the taxiway at 15km/h,though I applied full rudder and applied break. They just refuse to turn and always get out of the taxiway.

The second one happens during takeoff on both aircrafts,especially the MiG-15/17,100% RPM,takeoff flaps,no trim,full tank,and when I pull back the stick to rotate at a speed below 200km/h,the aircraft never responses,and the nosewheel never lifts,when the speed reach 200km/h,at that exact moment ,even without any control input,the plane suddenly lifts its nose and bounce into the airautomaticly.If I pull the stick at that point,the plane stalls(sudden drop of wingtips).

BTW,what are the proper ROTATE/APPROACH/TOUCHDOWN speed of yours? I flew the bearstudio MiG-15/17 and SectionF8 in FS,but they are totally different.

Could you guys help me? Thanks in advance.

We fly these alot over at the 51stfis and we find that when flying the Mig, it's best if you just let it take off on it's own with minimal input. That thing can take off and climb like a demon, so it is best to keep a steady hand on the stick and be ready with the gear handle and flaps if you use them. We don't. The sabre, especially the F-86F-25L, you can give it some nose up trim for take off and at about 140 KIAS, pull the stick back just a little and she'll rotate nicely. If you throw in some combat flaps (take off flaps are not really needed) you can pull up at a little lower speed.
Reply

Thanks Grant!
Reply

Hello All!

This is what is causing the problem?
The F-86 models I have seen such a problem
Please help me!

[Image: image-93D2_4B6920DF.jpg]

Regards,

Zsolt from Hungary
Reply

fallout3 Wrote:The second one happens during takeoff on both aircrafts,especially the MiG-15/17,100% RPM,takeoff flaps,no trim,full tank,and when I pull back the stick to rotate at a speed below 200km/h,the aircraft never responses,and the nosewheel never lifts,when the speed reach 200km/h,at that exact moment ,even without any control input,the plane suddenly lifts its nose and bounce into the airautomaticly.If I pull the stick at that point,the plane stalls(sudden drop of wingtips).

Sabre will even do this when loaded with bombs. Pretty amazing.
Reply

Clearly, many have now flown the F86 for a while so perhaps your input re the control sensitivity issues will answer these questions:-

This applies to standard UP2.0 install with "-Mods" set.

1) The rotation does seem abrupt as indicated in a previous comment. In addition, once airborne a great deal of elevator down trim seems to be required for in trim handling. I won't document all the variables, fuel load etc. but it is very noticeably different to the other FMs for F80/84 at this stage of the flight model.

2) There is a large trim requirement (nose up) if you for instance fly a circuit pattern and level off at 1000ft after T/O in the action of pulling the power back (no change in speed....around 200 IAS)
This would seem strange as there is little "moment" in the drag thrust line to cause this.

3) Control sensitivity for the entire FM is considerably higher than the other jets.

The more experienced IL2 chaps amongst you will have more than likely got used to these features but from one of the chaps in our squad who actually flew the F86, these issues are apparent and did not exist IRL.

Could someone enlighten us?

Nicholaiovitch :?:

Edit:-
Since installing the "Freddie" cockpit at SAS and thus enabling the "Mods" folder, the FM has changed and most of the above does not apply. it seems that the STD folder in the "Mods" of UP2.0 having been enabled has an influence on FM. Could someone clarify that?
Reply

Well...it's coool to know how to kick off migs but it seems that my ace wingmen don t know how to do it....

I have enough to find me alone against two untouchable rookies MIG-15s that have just shut down in a few minutes my three poor aces F-86F wingmen.....no?


Those Korea MODS are great but there is a problem with the MIG supremacy of the sky just not realistic compare with the historic reality....

Each time you play a US campaign with sabre it s just a F-86A/F slaughter...I think there is something to do here to correct this....
So if the differences beetween the MIGs and the F-86F are correct then there is a big problem with the US AI....Meanwhile I stop playing Korea campaign........


thanks
Reply

I have huge lagg in teh Sabre cockpit @_@
Reply


Forum Jump:


Users browsing this thread: 1 Guest(s)