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BlackCatClaws
02-15-2004, 11:27 AM
Hi il2 fans. I recently have red an article on energy management on SIMHQ . The article explains how to read the "doghouse" graphs and employ the information in fighter tactics.
Since then i am trying to fang the graphs on il2FB planes with no success. Please let me know if you have an idea where to find them.

Here is how they lookhttp://www.simhq.com/_air/images/air_011a_5.jpg

Below two planes are compared.
http://www.simhq.com/_air/images/air_011a_6.jpg



Thank you.

BlackCatClaws
02-15-2004, 11:27 AM
Hi il2 fans. I recently have red an article on energy management on SIMHQ . The article explains how to read the "doghouse" graphs and employ the information in fighter tactics.
Since then i am trying to fang the graphs on il2FB planes with no success. Please let me know if you have an idea where to find them.

Here is how they lookhttp://www.simhq.com/_air/images/air_011a_5.jpg

Below two planes are compared.
http://www.simhq.com/_air/images/air_011a_6.jpg



Thank you.

georgeo76
02-15-2004, 11:43 AM
Hey, those SimHQ (http://www.simhq.com/_air/acc_library.html) articles are really good. Suggested reading for all pilots

http://webpages.charter.net/Stick_Fiend/images/buck2.gif
"I don't think it's quite fair to condemn a whole program because of a single slip-up. "
Fiend's Wings (http://webpages.charter.net/Stick_Fiend)

BlackCatClaws
02-15-2004, 12:38 PM
Hey. I think those articles are very good too.
MY QUESTION WAS :IF ANYONE KNOWS IF IT IS POSSIBLE TO FIND THE ENERGY GRAPHS FOR IL2FB PLANES.

horseback
02-15-2004, 01:39 PM
Don't KNOW that this is right, but if you look at the chart comparing the Spit MK IX to the MK V, the vertical axis is labelled "dps" of degrees per second.

The horizontal axis is labelled MPH-miles per hour.

The left half of the doghouse's 'roof' is labelled 2g up to 6g, at the intersection points of the curved lines leading from the right half, which I assume to mean gravities pulled in the turn at the intersecting dps and mph points.

The right half of the 'roof' is labelled 400ft at the peak of the 'roof' down to 900ft at the intersections of the straight lines from the left, and I'm guessing that this refers to the feet per second travelled in the turn at the speeds on the corresponding points in the horizontal line.

Hopefully, someone with some real knowlege will either confirm or correct my guesses and we can ALL learn how to use these charts.

Cheers

horseback

"Here's your new Mustangs, boys. You can learn to fly'em on the way to the target. Cheers!" -LTCOL Don Blakeslee, 4th FG CO, February 27th, 1944

III.JG11_BobCat
02-15-2004, 03:26 PM
E-mail me for an excel spreadsheet with data for all FB aircraft and complete documentation.

rdavey99999@net.net.au

Remove the 99999 after my name.....

Bob

BlindHuck
02-15-2004, 08:25 PM
I'm going to suggest that xxxft is turn radius (diameter? whichever makes more sense after I think about it http://ubbxforums.ubi.com/images/smiley/16x16_smiley-indifferent.gif ).

"I race full real exclusively in IL2:The Forgotten Battles." - Mark Donohue

Magister__Ludi
02-15-2004, 08:51 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by BlindHuck:
I'm going to suggest that xxxft is turn radius (diameter? whichever makes more sense after I think about it http://ubbxforums.ubi.com/images/smiley/16x16_smiley-indifferent.gif ).

"I race full real exclusively in IL2:The Forgotten Battles." - Mark Donohue<HR></BLOCKQUOTE>

Yes, it is turn radius. The crossing point between tightest turn radius and X axis is the stall speed, indicating that planes with lowest stall speed have the tightest turn radius (this is why by lowering the flaps the turn radius becomes tighter, the stall speed is decreasing). Also the planes with lowest stall speed have the best instantaneous turn rate - sustained turn rate is another matter though, it depends also on power loading, Cd0, aspect ratio (among the most important). Sustained turn rate is indicated by the (red, blue) line in the middle, close to 3G black line. This is normal because most ww2 fighters could sustain 3G turns (almost all jets in service after the '60s are capable of sustaining 7G, making turn comparisons very easy, turn characteristics can be computed simply from stall speed). Dotted lines parallel with sustained turn line are the constant speed loss/gain lines (measured in ft/s) IIRC.

JG14_Josf
02-15-2004, 09:56 PM
On the constant speed loss/gain lines or lines of specific excess power; does it figure that a plane with lines closer together, above the Ps=0 line, will suffer greater loss in turns?

For example:
Imagine a planes performance being superimposed on the first chart above and imagine that the new plane has the first -20 dotted line placed closer to the solid 0 line; would the new plane with the lines closer to the Ps=0 suffer greater energy loss at the same speed same turn rate and same g force as the plane already shown in the diagram above?

In other words the plane with the negative Ps lines closer to the Ps=0 line will suffer the same energy loss at a lower turn rate, at less g force, and at a slower speed.



Is it also true that a plane with closer dotted lines under the Ps=0 line would increase energy at a faster rate than a plane with equal value lines further apart?

The example above has a plane that increases specific excess power at 20 ft/s for a 2g turn at 250mph in a 9 degrees per second turn so a plane with a dotted line for 20 ft/s that was higher or closer to the Ps=0 line may have a 20 ft/s increase in specific excess power at 2.5g and 275mph with a 10 dps rate turn.

Closer possitive Ps lines above the Ps=0 line indicate a plane that will lose energy faster in turns or climbs.

Closer negative Ps lines below the Ps=0 line indicate a plane that will gain energy faster in dives and maintain energy better in nose low turns.

This is really something to think about since it seems to me that this condition may illuminate why heavy planes tend to dive better and turn worse than lighter planes.

I guess it depends upon how specific excess power lines actually do show up on the charts. Will a plane show consistantly closer together lines above and below the Ps=0 line or can a light plane have wide spaced positive numbers above the line indicating an ability to turn hard without a high loss of energy while the light plane also has close together negative Ps lines under the Ps=0 line indicating high increases in excess power or acceleration as the turn is eased off and or the plane is vectored down.

Can one plane have wide spacing possitive Ps lines and close spaced negative Ps lines?

It appears to me that these energy maneuverabiliy charts with the Ps contours would be extremely valuable when trying to figure out tactics for specific plane matchups.

When a planes Ps contours are superimposed over anothers it should be obvious which plane can turn hard and maintain energy better as well as showing which plane accelerated better after the turn simply by looking at the spacing of the lines from Ps=0.

JG14_Josf
02-16-2004, 01:19 PM
Knowing a planes relative performance capabilities compared to an opponents is crutial when determining how to conduct combat.

A pilot with an understanding of relative advantage and disadvantage can maneuver for advantage and avoid maneuvering at a disadvantage.

Basic relative performance characteristics become known quickly in combat. The faster plane can catch or out run the slower plane.
The better climbing plane can catch or out run the less capable plane in a climb.

Turn performance is more complicated.

If one plane has a large turn rate advantage over the other plane then the comparison for tactical purposes is easy to judge.

The 262 pilot should know not to turn against an I-16.

When two planes have similar turn performance capabilitis the pilots in combat will learn that one plane may turn better when combat is fast while the other plane may turn better while the combat is slower.

This understanding leads the information effort toward a best turn speed performance number.

This number itself is complicated and can be further divided into two best turn speed performance numbers.

The effort to determine precise relative performance capabilities becomes more imortant to the pilots as performance capabilities become less varied and more similar such as the Spitfire comparison in the second chart on this page.

The pilot armed with the knowledge available with the chart has an advantage over a pilot without this knowledge.

Using this knowledge is, of course, another matter.


The basic turn performance information shown in the Spitfire comparision chart above is useful in combat because it shows how one plane can be flown to advantage against the other in combat.

If both plane meet head-on at the same speed and the same altitude the Spit V pilot would be advised to use angles tactics, or in other words if both planes were to maximize turn performance at the merge the Spit V would soon be in a possition to fire upon the Spit IX.

The Spit IX pilot would have the understanding based upon the information in that chart that his tactics for this combat situation would favor energy tactics. Simply put the Spit IX pilot should know to avoid turning hard against the Spit V. The Spit IX pilot must use some other tactic.

According to the second chart above the Spit V will be able to turn at 23 degrees per second if he holds the turn speed at 150 mph pulling 3gs.
At the same speed the Spit IX pilot will be almost falling out of the turn unable to avoid a stall and his turn rate will be at least one degree less per second at lower g force.

The Spit V can turn a tighter turn pulling more Gs at slower speeds than the Spit IX

But for how long can the Spit V continue this effort in turning?

What if the Spit V pilot did not shoot the Spit IX in the first 360 degrees of turn?

The 2nd chart above assumes the performance values shown are continuous and sustainable.

The Spit IX had a more powerfull engine. Is it possible that the Spit IX could go from a high speed turn to a low speed turn with a greater reserve of energy than the Spit V? Is it possible that the Spit IX would not lose as much energy during a maneuver?

Is it more likely that the Spit V would retain energy better than the Spit IX due to a lower wingloading and ligher weight?

What is missing on the Spitfire comparision chart above is the energy loss/gain information.

It is not likely that both planes would have the exact same dotted lines of specific excess power. One is likely to have the first negative 20 dotted line above the other and this condition indicates that the one with the lower dotted line, the one with the first -20 dotted line closer to the 0 line is going to burn up that -20 fps sooner that the plane with the -20 dotted line higher up the chart.

Is this not true?

With this specific excess power information the pilot is armed with additional usable information.

If the one plane has (for lack of a better term) an energy bleed advantage then the pilot of the plane with the energy bleed advantage can see under what conditions his plane will gain an energy advantage over the opponent.

An ability to gain an energy advantage is very valuable in a situation where the opponent has a turn performance advantage. This information is vital for the employment of energy tactics.

If the information is not available on charts then the pilot employing energy tactics must find out in practice if maneuvering can result in an energy gain.

The pilot armed with this information would know his planes relative capability in gaining an energy advantage even before the fight began.

Going back to the comparison of Ps lines above and below the Ps=0 line the combat pilot could also know his planes vertical manevuering advantages and dissadvantages.

Wouldn't the plane with the closer spaced possitive lines below the Ps=0 line have an energy gain advantage in a nose low turn, or a dive advantage in an unloaded dive, and a zoom advantage in an unloaded zoom climb, or am I reading too much into the chart?

[This message was edited by JG14_Josf on Mon February 16 2004 at 12:33 PM.]

Insuber
02-16-2004, 01:42 PM
BlackCat,

It appears that the professors here aren't giving you an answer to your simple question; here is an useful link:

http://sturmovik.webzdarma.cz/download/utility/il2c_v22.rar

The utility is IL2 Compare v. 2.2.

Regards,
Insuber

JG14_Josf
02-16-2004, 02:24 PM
Insuber,

Are you trying to insult someone?

Who are these professors?

Do you find no use for open discussion?

Would you prefer a simple bump?

Would it be appropriate in the future for me to simply keep my thoughts to myself?

Should I open a new topic instead of adding to this one?

I do want to figure out how to communicate more effectively.

I sure don't want to impose on anyone, but the subject matter i.e. Turn performance charts do hold my interest.

Alex_Voicu
02-16-2004, 02:35 PM
Check out this page:
http://www.alexvoicu.home.ro/enbl_comp.html
The tests were done in FB v1.11, but you may find them interesting anyway.

JG14_Josf
02-16-2004, 03:21 PM
Alex_Voicu,

Very interesting.

I wonder how much more accurate a test could be conducted if two players turned one behind the other during an on-line session and use the data from both player's recorded sessions.

Your test results indicate to me that the IL2/FB version 1.11 fight between the K4 and LA7 would be difficult for the K4 pilot trying to use energy tactics.

If the first chart above on this page were showing the Ps negative dotted lines of the LA7 then would it be correct to simply double the negative numbers to compare the K4 negative Ps lines to the LA7 negative Ps lines?

Does your data show that in that version of the game; during an equal turn between both planes the K4 would bleed energy at twice the rate of the LA7?

For instance if the LA7 followed the K4 in a 360 degree turn and at the end of that one turn the K4 dropped from 500kph to 200kph; the LA7 would only drop to 350kph?

Is the relative energy loss rate linear?

Thanks for the link.

And thanks for the link to IL2compare.

III.JG11_BobCat
02-16-2004, 04:26 PM
The III/JG11 speadsheet also includes PS=0, max TAS and dive speeds...

BobCat

Alex_Voicu
02-17-2004, 08:22 AM
[QUOTE]Originally posted by JG14_Josf:
Alex_Voicu,


For instance if the LA7 followed the K4 in a 360 degree turn and at the end of that one turn the K4 dropped from 500kph to 200kph; the LA7 would only drop to 350kph?

Is the relative energy loss rate linear?
----------------------

The energy is a function of squared speed, and i defined the energy bleed as the decreasing rate of the kinetical energy of the plane with time (the first derivative of the kinetical energy). The speed difference at the end of the turn will be much lower, but still the La7 had a big advantage. I suppose i could calculate what you suggested, but the tests were done in V 1.11, so now it's too late.

JG14_Josf
02-17-2004, 09:54 AM
Alex_Voicu,

Do you know if it is possible to find the conditions at which a plane will turn the greatest rate at the least cost in energy?

For example a plane will turn the least rate with minimum lift or g and a plane will turn the maximum rate with the maximum lift or g force. However a wing may become much less efficient at creating lift as the angle of attack changes.

So do you know if a plane will have an area of best turn efficiency where above this turn rate the energy loss per degree of turn is greater and below this optimum turn rate the degree of turn per unit of energy loss is less?

If this is true then do you know if this condition is modeled in the game?

Alex_Voicu
02-17-2004, 02:48 PM
Maybe it's possible to find out, but i would need to continue the tests using lower stick deflections. Unfortunately i'm quite busy right now - too much to do on the Tempest model.

BlackCatClaws
02-17-2004, 05:33 PM
Insuber
Bobcat
Alex

Thank you for trying to answer my question.

Insuber I dont know how to open your file. Do i need some softwere?

Bobcat I have sent u an email and i cant' wait for those spreadsheets.

Alex Nice work! I will conduct some testing of my own using your methods,if dont mind of coarse.



Everyone , i took the two grophs abouve from the article that axplains how to read them. here http://www.simhq.com/_air/air_011a.html

JG14_Josf
02-17-2004, 08:10 PM
WinRAR (http://download.com.com/3000-2250-10007677.html)

CPS_Shadow
03-12-2004, 11:36 PM
Anyone know when version IL2Compare 2.3 will be availiable to the general public?

03-13-2004, 12:27 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by CPS_Shadow:
Anyone know when version IL2Compare 2.3 will be availiable to the general public?<HR></BLOCKQUOTE>

2 weeks ago. You can get it from Checksix, but their server seems to be hosed right now.

CPS_Shadow
03-13-2004, 01:03 AM
Ok then... any one have a copy that they can put up for download? I'd really like to get my hands on the new data.

CPS_Shadow
03-13-2004, 10:40 AM
Found it thanks http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif

http://www.silver.ru/soft/il2c_v23.zip

03-13-2004, 01:12 PM
Great! I didn't know about that source. Thank you. http://ubbxforums.ubi.com/infopop/emoticons/icon_smile.gif