Fc2.0 F15 + su27 engine question

[borchi_2b]

hi folks.

 

i was wondering about the TWR about the su27 and about some engine data.

 

i just found this SFM_Engine.lua in the

Eagle Dynamics\LockOn Flaming Cliffs 2\Scripts\Aircrafts\_Common

folder

 

these are the numbers gioven in there, ist there anybody of the defs team who can explain the values, and where you got them from?

 

 

-------------------------------------------------------------

-- SFM Engine data.

-- Copyright © 2004, Eagle Dynamics.

 

-- the file is not intended for an end-user editing

 

Su_27 = 3

Yak_40 = 57

f_15 = 6

A_10 = 17

 

--------------------------------------------------------

SFM_engine_table = {}

 

SFM_engine_table[su_27] = {

typeng = 1,

dcx_eng = 0.0124,

hMaxEng = 19.5,

dpdh_f = 14500.,

dpdh_m = 7000.,

engtab1 = {

-- M Pmax Pfor

0.0, 135000., 205000.,

0.2, 124000., 175000.,

0.4, 114000., 171000.,

0.6, 110800., 180000.,

0.7, 109900., 192000.,

0.8, 109900., 210000.,

0.9, 109900., 228000.,

1.0, 110800., 240000.,

1.1, 113400., 256000.,

1.2, 119400., 265000.,

1.3, 134100., 279000.,

1.5, 155000., 300000.,

1.8, 165000., 331000.,

2.0, 165000., 356000.,

2.2, 165000., 375000.,

2.5, 165000., 386000.,

3.9, 165000., 270476.

}

}

--------------------------------------------------------

SFM_engine_table[f_15] = {

typeng = 1,

dcx_eng = 0.0124,

hMaxEng = 19.5,

dpdh_f = 14000.,

dpdh_m = 6000.,

engtab1 = {

-- M Pmax Pfor

0.0, 115000., 212000.,

0.2, 94000., 200000.,

0.4, 92000., 205000.,

0.6, 103000., 207000.,

0.7, 105000., 210000.,

0.8, 105000., 220000.,

0.9, 105000., 235000.,

1.0, 107000., 250000.,

1.1, 103000., 258000.,

1.2, 94000., 268000.,

1.3, 84000., 285000.,

1.4, 71000., 300000.,

1.6, 34000., 318000.,

1.8, 19000., 337000.,

2.2, 17000., 370000.,

2.5, 19000., 390000.,

3.9, 82000., 310000.

}

 

so can you say specific what tabel area is what and which data format the falue s are, somethink like kN for example.

 

plus are that the original datas of the su27?

if i am suming right, what the table say, the table is not correct, unless there are mature diffrences to what the turbine factory for the su27 states.

 

i am looking forward to get some informations how to understand this script lua

[EtherealN]

One very important thing:

 

Do not stare yourself blind at those values.

 

Basically, a cursory glance at those values will give the impression that things are wrong. But they're not - they are tweaked to make sure that the input value + SFM = as close to real parameters as possible. So due to some of the peculiarities of the simulation engine, some values have to end up "strange".

 

That said, the Eagle currently is too strong at less than mach 0.4, this will be corrected in the patch.

[mikoyan]

if you drop the flaps on the eagle you can kill an su-27 even if it is on your 6, you can also do endless loops without stalling, you can do a 90 degree up pull stop at 0 speed and the apply full power and still go up accelerating, you can out-turn the su-27 without using full power most of the time...so in other words the eagle is in god-mode this needs to be addressed seriously.

[71st_Mastiff]

where you been? It's already being fixed...

 

if you drop the flaps on the eagle you can kill an su-27 even if it is on your 6, you can also do endless loops without stalling, you can do a 90 degree up pull stop at 0 speed and the apply full power and still go up accelerating, you can out-turn the su-27 without using full power most of the time...so in other words the eagle is in god-mode this needs to be addressed seriously.

[combatace]

where you been? It's already being fixed...

 

Can you tell me when was the fix released after FC2.0 release and where is it????

[mikoyan]

where you been? It's already being fixed...

 

uh? where?:huh:

[104th_Crunch]

In regard to the F-15 slow speed turning, It hasn't been fixed yes but has been confirmed that it will be fixed in the upcoming patch.

[GGTharos]

The data format is Mach, kN, kN (MIL, AB)

 

The data comes from matching the FM to energy performance graphs, and while it may not be super-accurate, it likely reflects the general truth of how much thrust these engines produce at a given mach.

 

The table for the Su-27 is correct*. Tell me what you think is wrong, and I'll tell you what you don't know.

 

The table for the F-15, as mentioned before, is not correct under 0.4M. The thrust reflects an engine closer to a -229 at those speeds than a -220 and this will be addressed in the patch.

 

FYI, the -132 is a viable F-15C alternate engine ... who knows, maybe some day ... :music_whistling:

 

*subject to limitations of flight model. Particular thrust values may under of overshoot their RL counterpart slightly for a given mach value. Same for F-15.

 

 

so can you say specific what tabel area is what and which data format the falue s are, somethink like kN for example.

 

plus are that the original datas of the su27?

if i am suming right, what the table say, the table is not correct, unless there are mature diffrences to what the turbine factory for the su27 states.

 

i am looking forward to get some informations how to understand this script lua

Edited April 29, 2010 by GGTharos

[Nate--IRL--]

uh? where?:huh:

 

BEING fixed. As in, will be included in the patch.

 

Nate

[combatace]

The data format is Mach, kN, kN (MIL, AB)

 

The data comes from matching the FM to energy performance graphs, and while it may not be super-accurate, it likely reflects the general truth of how much thrust these engines produce at a given mach.

 

The table for the Su-27 is correct*. Tell me what you think is wrong, and I'll tell you what you don't know.

 

The table for the F-15, as mentioned before, is not correct under 0.4M. The thrust reflects an engine closer to a -229 at those speeds than a -220 and this will be addressed in the patch.

 

FYI, the -132 is a viable F-15C alternate engine ... who knows, maybe some day ... :music_whistling:

 

*subject to limitations of flight model. Particular thrust values may under of overshoot their RL counterpart slightly for a given mach value. Same for F-15.

 

You shouldn't be biased as you are in the developer's team.

[EtherealN]

if you drop the flaps on the eagle you can kill an su-27 even if it is on your 6

 

I've done that on 27's without deploying flaps. How? They didn't know how to handle the 27. 6 o'clock is not an automatic win position for the 27, it has to work for it's kills just like everyone else. It has certain advantages and a pilot that knows how to use them will be very successful. A pilot that does not know how to use them will die.

 

you can do a 90 degree up pull stop at 0 speed and the apply full power and still go up accelerating

 

Bull. I tried. I died. To an Su-27. ;)

 

you can out-turn the su-27 without using full power most of the time...

 

The Eagle has energy advantage. Stop thinking that the su-27 having angles superiority means an automatic win in BFM. It doesn't. You still have to know how to handle your aircraft. I've run into experienced Flanker pilots that beat me like I was flying a 747. I've also run into Flanker pilots that might as well have been flying a Cessna.

 

so in other words the eagle is in god-mode this needs to be addressed seriously.

 

If it's "god-mode" I wonder why the heck I die so much... :D

Ask GG, he bitches at me for it.

Edited April 29, 2010 by EtherealN

[GGTharos]

What in this factual answer was biased?

FYI, I'm not a developer.

 

You shouldn't be biased as you are in the developer's team.

[Boneski]

Too awesome! You are very lucky to get to fly both jets during your active duty career (Are you still active? Or are you on the ground full time now?)

You must be part of your countries Air Force Exchange program if you are active duty??

 

How many hours do you have logged in both the F-15 and Su-27 airframes?

There is nothing like turning real JP into noise!!!!

 

It does gives you great insight and a solid base of comparison between PC based flight sim application and Real world hours...

 

 

The data format is Mach, kN, kN (MIL, AB)

 

The data comes from matching the FM to energy performance graphs, and while it may not be super-accurate, it likely reflects the general truth of how much thrust these engines produce at a given mach.

 

The table for the Su-27 is correct*. Tell me what you think is wrong, and I'll tell you what you don't know.

 

The table for the F-15, as mentioned before, is not correct under 0.4M. The thrust reflects an engine closer to a -229 at those speeds than a -220 and this will be addressed in the patch.

 

FYI, the -132 is a viable F-15C alternate engine ... who knows, maybe some day ... :music_whistling:

 

*subject to limitations of flight model. Particular thrust values may under of overshoot their RL counterpart slightly for a given mach value. Same for F-15.

[GGTharos]

Got anything you can actually contribute?

[EtherealN]

It does gives you great insight and a solid base of comparison between PC based flight sim application and Real world hours...

 

I understand that you have never seen an aircraft operator's manual. Thankyou? :D

[mikoyan]

I've done that on 27's without deploying flaps. How? They didn't know how to handle the 27. 6 o'clock is not an automatic win position for the 27, it has to work for it's kills just like everyone else. It has certain advantages and a pilot that knows how to use them will be very successful. A pilot that does not know how to use them will die.

 

 

 

Bull. I tried. I died. To an Su-27. ;)

 

 

 

 

The Eagle has energy advantage. Stop thinking that the su-27 having angles superiority means an automatic win in BFM. It doesn't. You still have to know how to handle your aircraft. I've run into experienced Flanker pilots that beat me like I was flying a 747. I've also run into Flanker pilots that might as well have been flying a Cessna.

Energy advantage? yes the eagle is more powerful but I find hard to believe that I can pull the stick to the maximum and still outurn an su-27(at low altitude); that is not energy maneuvering at all, it is just too good to be true.

 

 

 

If it's "god-mode" I wonder why the heck I die so much... :D

Ask GG, he bitches at me for it.

 

Well I find hard to believe that if you pull your stick to the maximum the eagle won't stall at all. so I gues you can also pull the stick and do enless loops on the real airplane?

[RedTiger]

To summarize, for my own benefit and others, arbitrary numbers where applied to the sim to get the plane to perform the way it should? In effect, ED worked around the quirks of the SFM and tweaked numbers to inaccurate values so that the actual performance is close to the real thing?

 

In other words, except for the known F-15C problems, we should ignore the values in LUA and use the aircraft in the sim to plot a chart, then compare that chart to the real one, correct?

[GGTharos]

That is more or less correct. The thrust values will not be exactly what the real aicraft produces, but in most cases they will be in the right ballpark.

Just matching thrust-mach alone isn't going to necessarily give you the most correct performance due to, as you aptly said, the quirks in the SFM.

Basically you can have correct thrust values (Which may be hard to get for one) or correct ROT/Climb values ... which is probably what you actually want to have in the end.

 

To summarize, for my own benefit and others, arbitrary numbers where applied to the sim to get the plane to perform the way it should? In effect, ED worked around the quirks of the SFM and tweaked numbers to inaccurate values so that the actual performance is close to the real thing?

 

In other words, except for the known F-15C problems, we should ignore the values in LUA and use the aircraft in the sim to plot a chart, then compare that chart to the real one, correct?

[borchi_2b]

hmm, well but the f1 engine hat at a speed of xxx kn, which sums up to about 244kn ata speed of mach0.0.

 

so when your table says it is under full ab, for both engines 207kn, then where are all the other KN fone too?

 

birdstrike or reduced thrust for survivablity during non combat?

[EtherealN]

I'm not sure I understand what you are asking, Borchi.

[GGTharos]

No, it is installed thrust. The rated thrust (the one usually advertised, ie. for example when they tell you flanker engine has 12.5t thrust) for an engine is the bench thrust, with a special inlet that lets it attain full thrust at M0.0.

 

Once you install it on a plane though you suffer losses due to the aircraft inlet, and typical installed thrust is approximately 80% of rated thrust at M0.0.

 

hmm, well but the f1 engine hat at a speed of xxx kn, which sums up to about 244kn ata speed of mach0.0.

 

so when your table says it is under full ab, for both engines 207kn, then where are all the other KN fone too?

 

birdstrike or reduced thrust for survivablity during non combat?

[borchi_2b]

ahh i see, thats werethere was made the mistake with the f15c, cause in the lua it has the max thrust of 212kn, which would be unrealistic to your words

[GGTharos]

Yep, exactly :) F-15 thrust a low mach is too high - ie. no installed engine loss.

 

ahh i see, thats werethere was made the mistake with the f15c, cause in the lua it has the max thrust of 212kn, which would be unrealistic to your words

[borchi_2b]

this decribes the super agility compared to the mig29 and su27, at lower speeds, which you reach in bfm very fast.

 

i am looking forward to have that fixed, so then it might be possible to win against f15c in bfm again, right now, there is no real way, when you try to turn and turn and turn.

 

but the flapsissue of the eagle will be fixed too?

the issue of gaining speed by setting flaps ?

 

edit:

we figured that the aim120c has a greater gimble or search area then 55°, can you guys check on the again?

 

i have to see if i can find some tackviews of certain instances again

[GGTharos]

this decribes the super agility compared to the mig29 and su27, at lower speeds, which you reach in bfm very fast.

 

i am looking forward to have that fixed, so then it might be possible to win against f15c in bfm again, right now, there is no real way, when you try to turn and turn and turn.

 

but the flapsissue of the eagle will be fixed too?

the issue of gaining speed by setting flaps ?

 

Flaps were being worked on, as you may have noticed in the big thread about all this stuff.

 

edit:

we figured that the aim120c has a greater gimble or search area then 55°, can you guys check on the again?

 

i have to see if i can find some tackviews of certain instances again

 

It is 60 deg in game, as it is for a lot of other missiles. I don't think it's going to get touched at this point, and in any case, 5 deg won't kill you ;) Far better than the 90 deg gimbal it had before.

 

Regarding the search specifically, not much that can be done about it ... in a way it replaces some missing properties of the ARH missiles; at any rate, ARH should no longer scan when maddogged (As opposed to when losing lock).