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View Full Version : Fw-190 "lets talk. need math expert" :)


Ltbear
01-03-2011, 10:19 AM
The 190 have had a turbulent life in IL2. Main thing was the "Bar" then there was damedge model etc.

I have for a long time (4+ years) Been reading data and documents relatet to this plane.

In many cases the evaluation documents from the allied side have a "this was not a fighter version or this was a dameged plane etc" in it.

In general im pretty happy with it, i can live with the "bar" and the damedge model, but the acceleration have always been an isue for me. Its wierd that it is normaly mentioned on par with allied planes from the same time period when it accelerates like it does in the game.

What i do know is that one who have a deep understanding with math and who have numbers that are close relatet to a planes performance, can calculate a data set for another plane, as long its the same model, with only minor modifications.

I cant do it, my math is not good enough for that and i dont have the understanding that is required to do this, but maby one around here have the brain for it, and will consider it a fun little challenge.

The document i post here are not about anything but the acceleration for me. There is stuf about turning etc, some might know it, if im lucky someone might have a better one with better numbers. This one are a test flight of the 190A-4 vs a F4U-1 and a F6F-3

The documents have some numbers about climp, speed and acceleration between the airplanes. The planes are ingame, so we have a set of data for 3planes ingame, this document from a RL test of the FW-190A-4 and the 2 others, that give us 2 reference points to calculate anything about the 190.

The 190 are flying against brand new production planes, but the running time for the 190 is unknown, but you can find the real data of a 190A-4 production (as statet by manifacturer)

Main problem is that this test is a jabo version. Well in general its a 190A-4, but there are made modifications, these modifications are some of the challenge for the math head. In general the jabo and fighter version are the same, main diffrence is the weight, so the math head need to calculate the performance difference between the testet plane "pr document" to the manifactoring data for the fighter version.

Again. This is not about turning, manouvers etc, this is only about the acceleration of the 190A-4.

If we here can get enough data i know math can solve the mystery about the "truck feeling" of the 190`s

If numbers are rock solid there is no reson to doubt the numbers.

So for the fun of it it could be a fun project, hopefully a small topic clean of to much bias etc. This is about raw numbers, alot of math and hopefully a place where alot, like me can get a bigger understanding of the math behind planes.

I will give the test document and some other data. Maby someone can test the 190A-4 ingame against the two other planes so we can have the game data.

Then we need someone who have a math brain to tell us what we need more to be able to make a estimatet data sheet for the acceleration of the 190A-4 and then finaly compare that with the 190A-4 ingame :)

Hope some others would think this could be a cool idea

1. Test flight document
http://www.wwiiaircraftperformance.org/fw190/ptr-1107.pdf

Please post data if you have it

Aircraft specifications of the 190A-4

Think the most important numbers are the engine power, and the weight, but there is proberbly something else lol (edit, like drag)

LTbear

IvanK
01-03-2011, 10:50 AM
This is a well known document. Sadly it only provides relative comparisons in terms of 1G acceleration, no direct numbers appear in the document.

Ltbear
01-03-2011, 10:55 AM
well my idea was to get all the numbers needed so one with a prestine math mind would have the numbers to calculate a data set for the 190A-4 about acceleration.

There should be enough data outthere to be able to make a estimatet calculatet acceleration data set for the 190A-4

It is this data i would love to se set up against the ingame one. Nothing "its wrong etc" just some math vs ingame plane thats it :)

LTbear

(i bet charlie from numbers could do this in 15 mins lmao)

From the document we

climping speed
Horizontal speed
Aceleration

We have it for different altitudes

We then "hopefully" can get the manifactures data for the performance for the 190A-4

We then have the ingame data from all 3 planes.

This give us some numbers. Some math can provide the others. (yes some will be estimatet) but again its not a perfect world

With enough data someone will be able to make a calculatet data set. This we hold up against the ingame plane and se how correct/wrong it is.

Its nothing but a fun project that ends in a estimatet number/numbers

Im reading hard up on math that involves this type of calculation lol....

6S.Manu
01-03-2011, 11:17 AM
Climb rate, acceleration and speed of 190s are quite corrected... the problems lie in other aspects.

Ltbear, you have a PM.

IvanK
01-03-2011, 11:23 AM
Rate of climb data provides a measure of Specific excess Power (Ps). You can then use that value to determine point source 1G acceleration data. In some of the testing I have done in IL2 there was a good correlation between Rate of Climb data and the derived 1G linear acceleration when actually put to in game flight test. I am sure there are some generalisations in this method and I am certainly no mathematician, but its a start. Again I stress its only point source data.

This was the method I used.

Ps = Rate of Climb in units per sec.
g= Acceleration due to gravity (32.2fps or 9.8msec)
V= TAS in fps or mps

1g Accel = (Ps x g )/V

So take an aeroplane with an instantaneous Climb rate of say 20msec at 300Kmh (83.1mps)

1gAccel = (20 x 9.8 ) / 83.1
1gAccel =2.358msec or 8.5Kmh/sec (again its point source data)

Ltbear
01-03-2011, 11:44 AM
Climb rate, acceleration and speed of 190s are quite corrected... the problems lie in other aspects.

Ltbear, you have a PM.

got it and read it :)

tx

Ltbear
01-03-2011, 11:46 AM
Rate of climb data provides a measure of Specific excess Power (Ps). You can then use that value to determine point source 1G acceleration data. In some of the testing I have done in IL2 there was a good correlation between Rate of Climb data and the derived 1G linear acceleration when actually put to in game flight test. I am sure there are some generalisations in this method and I am certainly no mathematician, but its a start. Again I stress its only point source data.

This was the method I used.

Ps = Rate of Climb in units per sec.
g= Acceleration due to gravity (32.2fps or 9.8msec)
V= TAS in fps or mps

1g Accel = (Ps x g )/V

So take an aeroplane with an instantaneous Climb rate of say 20msec at 300Kmh (83.1mps)

1gAccel = (20 x 9.8 ) / 83.1
1gAccel =2.358msec or 8.5Kmh/sec (again its point source data)


sorry to bother you :)

Did you test the 190A-4 and hold the results up against manifatures data?? ( i know the data normaly are in the "happy" end, but it gives an idea if its worth digging more into this subject :)

LTbear

Jaws2002
01-03-2011, 07:56 PM
The problem with the Antons in game is the function of the komandogerate/prop pitch at low speeds. At low speed the FW190's cant maintain the rpm.
This leads me to belive the prop pitch is too corse, just like trying to climb a hill in high gear, or having no first and second gears in the gear box and the lower gear being third. You can actually try that. Go out and try to drive the car using only from third gear up. You can feel the engine strugling.

That's exactly how our Antons behave.

JG27CaptStubing
01-03-2011, 08:08 PM
The auto prop feature of the game has always been off for the Anton Series... Any season FW driver in IL2 uses manual for this very reason. In fact once used it starts to behave a bit more like the Fighter version. You can get more climb more speed and acceleration. Not by huge amounts but it's noticeable

Jaws2002
01-03-2011, 08:21 PM
Yeah. The first thing you do when starting a mission in Anton is to sitch the prop to manual. :mrgreen: I used to do that before starting the engine. :mrgreen:

JG4_Helofly
01-03-2011, 08:47 PM
Wasn't there an acceleration test in the ubi forum once? As far as I remember, the problem lied in the acceleration at low speeds.
Very understandable when you take off. I always thought that Oleg programmed an automatic parking break for the 190 :)

As it has been said: The problem might very well be the Kommandogerät which can't handle the prop pitch at low speeds.

engarde
01-04-2011, 08:49 AM
I think this means well, but is highly flawed.

The engine? Just not a perfect system.

Wear and tear, electrical system health? Are all cylinders firing? Every cylinder getting the same intake charge? No valve springs affecting exhaust or intake?

Will every single FW190 of each type provide the identical performance of every other same type?

And what about weather, ie air density or temperature.

You are demanding a digital reproduction of a very analogue system.

Which is tiresomely representative of all those that complain ceaselessly about their favourite aircraft.

What about engine manufacturing quality 70 years ago?

What about fuel quality 70 years ago, amidst resource denial?

What about every little thing that affects the performance of an aircraft that CANNOT be precisely captured with mathematics?

Just have a look at modern racing. With all the tech and knowhow and experience available now, why do teams bother trying to improve their vehicles?

Isnt it simply a case of using exactly the same settings for every race track every time you go there?

;)

Useless.

FG28_Kodiak
01-04-2011, 01:36 PM
Complete FW-190A8 Aircraft Handbook (in English) with Performance Data from Focke Wulf:
http://www.mediafire.com/file/3mzmmykwgoo/fw190a8.pdf

enjoy!

vparez
01-04-2011, 01:50 PM
Complete FW-190A8 Aircraft Handbook (in English) with Performance Data from Focke Wulf:
http://www.mediafire.com/file/3mzmmykwgoo/fw190a8.pdf

enjoy!

Do you have any information who compiled and printed this, and where was it published? I guess it is a translation of an official document? Just being curious.

Anyway, what LtBear is asking for is just not obtainable. I tried to do this for a plane I am working on, whose flight characteristics are unknown due to lack of flight test data, and the result is just not verifiable...

I used the Theory of wing sections (Anderson) for computation of lift, and I ended up with some values which were overestimating the critical AoA of this aircraft (based on similar aircraft and their AoAcrit in IL-2) by 3-4 degrees.

Anyway, in order to do this, you have to have a complete understanding of how the FM is represented in this simulation, and when I say "complete" I mean complete as in the case of its creator, if you get my drift.

FG28_Kodiak
01-04-2011, 01:59 PM
I've downloaded this from tailwheel.nl (now the side seems to be down) years ago. Don't know if they made this translation or others.
The translation is accurate, i ve the orginal german documents.

vparez
01-04-2011, 02:15 PM
I've downloaded this from tailwheel.nl (now the side seems to be down) years ago. Don't know if they made this translation or others.
The translation is accurate, i ve the orginal german documents.

Cool, thx! ;)

K_Freddie
01-04-2011, 09:27 PM
LTBear..
I think this has been chewed to death on the UBI forum and if I'm not mistaken about this being the same document discussed, some points to consider.

- The FW tested was not at peak performance for fuel, maintenance reasons.
- It looked to be a Jabo version which generally had more armour plating = heavier.

You'll also notice a glaring contradiction in the document you linked.
The bit about how easy the engine management was, and how the allied test pilots found this to be a problem ????

From this document you cannot conclude a definitive acceleration/turning/performance figure for the FW.

:)