Aircraft Performance

[usagold2004]

I recently did some testing of some IL2 aircraft and thought I'd post it for others and see if anyone else had data to share...

I did level flight tests at maximum continuous power with boost that would not over heat the engine. I did a pull to the vertical (80-90 degrees) for a zoom climb to stall. Airspeeds are Indicated Airspeeds, not True Airspeeds.

Level @ 20k - Zoom Climb
Bf 109 G10 265 mph - to 25k
FW 190 A8 250 mph - to 24k
P 51 D 270 mph - to 25k
Spit 9e 250 mph - to 24k
La 7 3B20 285 mph - to 25k+

they all seemed to be relatively close to data I could find on the internet (wiki) except the La7 which seemed to be significantly too high.

**I just recently found this site with real test data http://www.wwiiaircraftperformance.org/
*** here is a site if you are interested in how to calculate TAS and other stuff http://www.scenery.org/faq_aviation.htm

[Thunderbolt56]

Testing from 20-25,000ft and no Jug?

[usagold2004]

I know its sad. I just hate flying it bc I'm so bad at it, so I didnt test it.

[ZaltysZ]

Start altitude is the same (good)
Start speed is different (bad),
Stall (the end speed) isn't defined precisely (bad).

Even if you had tested by choosing the same pull up speed for every aircraft (lets say 250mph) and ended test at at 60mph, you still would have pretty insignificant results, because gained altitude would be almost the same (with minor difference). It would be so because of wide interval of speed. Aircrafts like FW190, P47, P51 would have edge in climbing while speed is very high and aircrafts like BF109 and Spitfire would have advantage in climbing at low speed. Your test had included low and high speed climbing, so, for example, what advantage P51 got at high speed, it lost at low speed; for Spitfire it was opposite - it lost at high speed, but caught at low speed. If you had partitioned altitude every 300 feet and had noted the time every aircraft reached every altitude mark, you would see that P51 gained half of altitude more quicker than other aircrafts and then lagged so badly that other managed to caught it.

The bottom line is that you need to fix start and end speeds and then plot 2 charts: "height vs time" and "height vs speed". From them you will be able to conclude at which speeds zoom should be initiated and terminated to again and advantage from zooming. Just by measuring gained altitude at wide speed interval you may get false feeling that aircrafts are balanced.

[usagold2004]

Zalty

You are talking about a different data set than I have given. Mine is not what you are looking for but I wouldnt say its bad...For the data I put, you can see what to expect from a coaltitude enemy flying at max continuous power. It doesnt address low speed turning performance because I'm not sure how to figure that out.

If anyone has any ideas on how to measure other aspects like zalty, post your data or share your ideas

[ZaltysZ]

Originally Posted by usagold2004

It doesnt address low speed turning performance because I'm not sure how to figure that out.

It has nothing to do with turning. You must understand that different aircrafts have different climbing curves. Some can 'hang on propeller' and some can't. Those, that can, have lower deceleration at low speed, however they often does not shine at high speed. Little example. P51 and BF109 begin pull up at the same altitude and high speed; initially BF109 lags behind in gained altitude (it seems like P51 is getting way), however after sometime distance between BF and P51 becomes constant and eventually it begins to decrease. Smart P51 pilot will terminate its zoom at the moment distance begins to decrease and will enter level flight. The end result (height) might be the same, but the climb is almost always very different.

Try to test Spitfire and P51 in a way I have described in my previous post. It will took some time, but I think it will be interesting for you.

Originally Posted by usagold2004

For the data I put, you can see what to expect from a coaltitude enemy flying at max continuous power.

As I said before, you may get in trouble (obviously in virtual dogfight) because of false feeling about aircraft performance based on your results of test. I will explain. If you are in P51 and enemy is in BF, you both may reach the same altitude before stalling, however you may reach it at different time and because BF recovers from stall more easily and earlier than P51, BF will win. I am trying to say that one aircraft can have big advantage over other aircraft despite you test shows that they both reaches the same altitude before stalling.

[IceFire]

Originally Posted by usagold2004

I recently did some testing of some IL2 aircraft and thought I'd post it for others and see if anyone else had data to share...

I did level flight tests at maximum continuous power with boost that would not over heat the engine. I did a pull to the vertical (80-90 degrees) for a zoom climb to stall. Airspeeds are Indicated Airspeeds, not True Airspeeds.

Level @ 20k - Zoom Climb
Bf 109 G10 265 mph - to 25k
FW 190 A8 250 mph - to 24k
P 51 D 270 mph - to 25k
Spit 9e 250 mph - to 24k
La 7 3B20 285 mph - to 25k+

they all seemed to be relatively close to data I could find on the internet (wiki) except the La7 which seemed to be significantly too high.

**I just recently found this site with real test data http://www.wwiiaircraftperformance.org/
*** here is a site if you are interested in how to calculate TAS and other stuff http://www.scenery.org/faq_aviation.htm

Curious which La-7 data you were using for testing? I've only found one source recently that gives any information of interest at all.

Right her: http://www.desertstar.co.uk/warbirds...formLa5La7.pdf

There are a couple of different La-7s tested too...and their performance varies drastically.

[Sonko]

Try this programm if you are searching for comparison data:
http://war.by-airforce.com/downloads...pare-4.07.html

[JG27CaptStubing]

Originally Posted by usagold2004

I recently did some testing of some IL2 aircraft and thought I'd post it for others and see if anyone else had data to share...

I did level flight tests at maximum continuous power with boost that would not over heat the engine. I did a pull to the vertical (80-90 degrees) for a zoom climb to stall. Airspeeds are Indicated Airspeeds, not True Airspeeds.

Level @ 20k - Zoom Climb
Bf 109 G10 265 mph - to 25k
FW 190 A8 250 mph - to 24k
P 51 D 270 mph - to 25k
Spit 9e 250 mph - to 24k
La 7 3B20 285 mph - to 25k+

they all seemed to be relatively close to data I could find on the internet (wiki) except the La7 which seemed to be significantly too high.

**I just recently found this site with real test data http://www.wwiiaircraftperformance.org/
*** here is a site if you are interested in how to calculate TAS and other stuff http://www.scenery.org/faq_aviation.htm

Nothing new. The LA7 has always been known to perform better than it does in real life. Ask your self this question. What country produces the LA7 and what country was this flight sim developed in?

If you go looking hard enough you will find out there are many many flaws with several of the airplanes.

It's been ignored for years.

[SturmKreator]

totally agreed