AH Fw190A8 making 350mph on the deck. Reason found :)

[R4M]

Heya     just want to answer a question that was asked by myself.    

I've been lately very interested in the AH Fw190A8's speed on the deck. The reason whas that, while in AH the A8 makes 350mph at 0feet, I have seen lots of sources saying that the A8 did 360mph on the deck.

I was very very surprised and interested when I saw in a FW document, dated in late 1944, that the Fw190A8 had a speed of 578km/hour@0m (360mph).

Chart is here: http://www.vermin.net/ta152/ta152-4.jpg


On the other side, in the original Fw190A8's pilot handbook's speed/climb charts (posted by vermillion last week) the speed on the deck was 350mph, exactly. The chart was dated March'45.


Vermillion, nor me, didnt knew the reason behind the discrepance in speeds...but now I found it. The first chart (completely in german, some of wich I have traduced by myself, a translator, and a big headache    ) lists the speeds of the planes WITHOUT an ETC501 bomb rack.

When I traduced this, I instantly opened the handbook's chart, and looked if the Fw190A8 in that study had ETC501 attached...

To my surprise...indeed it was...and up there in the middle of the chart there was this:

"Speed loss with ETC501 rack: 10mph at 6km, 7.6mph at 0km"

there are still 2.4mph missing somewhere at 0 feet   ...but other than that the "mistery" is now resolved.AH's Fw190A8 speed is pretty accurate.  



[This message has been edited by R4M (edited 03-06-2001).]

[Nath-BDP]

Heres a better one thats rotated AND translated, thanks to kirin.
 http://pobox2.zyan.com/~nath/bs/chrta.jpg

[This message has been edited by Nath-BDP (edited 03-06-2001).]

[R4M]

DOH! all my translation work for nothing, it was already done!!!!

lol  

[F4UDOA]

What is that blurb about take-off power, WEP and increased manifold pressure?

What's the manifold pressure at that speed?

[funked]

Nice job.

The 2.4 mph is from unit conversion error (578 km/h is 359 mph) and from chart reading error (Verm's translated manual shows 351 mph).

[fats2]

There was a question mark next to 'with movable gear flaps' in the translated chart, my guess is that means the inner gear doors. They were often removed from frontline aircraft.

I think they pretty much broke every time and ended up hanging open all the time. The correct operation was that they just opened when rising/lowering the gear.

Just a guess mind you.


// fats

[juzz]

???

The pilots manual graph says:

Without ETC 501
Undercarriage: Wheel doors fitted
External surfaces: Filled and polished

Speed at s/l = 544km/h, 565km/h with increased MAP

The translated table says:

Speed values without consideration of the drag increase due to compressibility, without ETC, with moveable gear flaps, filled surface and smooth painting.

Speed at s/l - 548km/h, 578km/h with increased MAP

Sounds like the table is actually calculated performance, and they overestimated the speed at low altitude?

Climbrate and speed at high altitude match almost perfectly in both sources.

[Hans]

Don't you guys think your nitpicking this game just a weee bit too much?

10mph...thats not much to argue about since a whole bunch of books could (and usually do) list diffenet figures.

Average them all out and go with it.  You can't use one source as a bible.

Hans.

[juzz]

Yeah, but it's a pity that the figures used for the Soviet fighters are the lowest of the low available...  

[fats2]

10mph is everything, you shoulda seen what a riot 7mph missing from P-51's top speed caused over at usenet.

That 10mph is less than 3% from a published figure of 360mph. I'd say it is accurate enough.


// fats

[Lepton]

Hehe. When you're trying to catch up or run away, that 10mph becomes really important  

[C_R_Caldwell]

 

Originally posted by Hans:
Don't you guys think your nitpicking this game just a weee bit too much?

10mph...thats not much to argue about since a whole bunch of books could (and usually do) list diffenet figures.

Average them all out and go with it.  You can't use one source as a bible.

Hans.

Hans, nobody is talking about figures pulled out of "books".Unfortunately, most of the literature on WW2 a/c is simply the result of authors copying data from certain popular, but sometimes incorrect sources.

For instances, William Green's excellent tome on military a/c types used by the Nazi Germany, "Warplanes Of The Third Reich", published in 1970 is regarded by many as the most comprehensive book on the subject.However, whilst most of the info within is very accurate, there are a number of glaring errors ie. he states the 109K-4 used 2 x 15mm MG 151/15 machine cannons in the upper cowl instead of 2 x 13mm MG 131 'heavy' MGs.

He corrected that mistake in his following book which was based solely on the 109 named "The Augsburg Eagle", but by then it was too late."Warplanes Of..." was (& is) such a popular, comprehensive & respect work, that *many* authors have simply copied the information within, added their own spin to it, then sold it to the public as new.This is lazy, & in many ways immoral, but it's dangerous too because these same people blindly regurgitated his data - INCLUDING the erroneous stuff.As you well know, you put garbage in, you get garbage out.

What we have been referring to here are not simply reference books, but (hopefully) original historical documents so that we can debate their voracity, & how they compare to each & the performance of a/c in AH.Some may think the distinction is subtle, but it in fact profound.

As far as 10mph is concerned, during a more than fleeting chase, 10mph down low can mean a *lot* of difference.If the performance off all the a/c in AH differed by 10mph, many of us would still complain, but at least the disparity would be homogenous.But if one a/c is slower by 10mph from its historical counterpart & another isn't (or is faster), the difference can be substantial.

[Glasses]

Same as the 18 degree sec missing from the 190FM I want the whole aircraft to be fixed not the crap we have right now those extra 18 degrees sec would make a whole lot of difference

------------------
Glasses---I may have 4 eyes ,but you only have one wing.
-----15 Spanische Staffel----
Tis not important how one goes,but who goes with you.

[fats]

I used to be like that too ( ask pyro! ); 10mph would've been everything 4 years a go. Now I just don't care anymore. I just get numb and start ignoring minor issues like this and still manage to have fun.

OTOH I can agree with you on relative performance though. So before yelling wulf ( excuse the pun ), check the other planes as well. And if a Typhoon is 10 mph too fast ( 20mph advantage thus ) on deck it doesn't matter cause it's supposed to be way faster than Fw 190A-8 anyway.

OTOH byt the time I must rely on a 'missing 10mph' I have already screwed up. My flying sucks and that 10mph wouldn't help me kill anyone.


// fats