Spit/109 sea level speed comparisons in 1.08 beta patch

[Kurfürst]

Originally Posted by TomcatViP

I hve in mind the gun barrel for sure. I think the rad were different. But I need to check this. There is also a good article on the net (in French probably) if you browse around "bf109" and switzerland ("Suisse"). Will try to have a look.

Yes I will check that, I had a good (IIRC German language) book about Swiss 109s, which helped me to ID J-347's WNr. and service record.

As for the gun barrels, I am not sure - one of the tests being waved about is explicitely about measuring the speed diff. between guns present/not present, and it's about 1 km/h.. I'd imagine different gun barrels amount to even less.

Rads look interesting though, this might account for something, but again, looking the Swiss test results, the difference is only about 8 kph at VDH, which from my experience, is an extremely good match for a serial production plane compared to the guaranteed specs!

Originally Posted by Holtzauge

Seeing you seem to be such an expert perhaps you would be so kind to point out what is wrong in my Me109E speed/alt chart and how it really should look like?

Well for one it probably has wrong data.. guessworked drag, guessworked wing effiencies, guessworked propeller effiency, manipulated until it fits one's agenda.

As Tagert said, garbage in... garbage out.

BTW, care to tell why you disappeared from allaboutwarafe forums? I am sure it's hell of a story.

[Holtzauge]

Originally Posted by Kurfürst

Well for one it probably has wrong data.. guessworked drag, guessworked wing effiencies, guessworked propeller effiency, manipulated until it fits one's agenda.

As Tagert said, garbage in... garbage out.

BTW, care to tell why you disappeared from allaboutwarafe forums? I am sure it's hell of a story.

I think people are aware by your modus operandi by now: If you don't like the message then discredit the messenger.

Me "disappering" is for no more sinister reason than for working on a book project. Believe me it's much more satisfying than arguing about your doctored data or sparring with your mathematically challenged pal Crumpp!

So if my Me109E data is so totally wrong then I guess this means that HoHun's charts are off the wall as well because we get the same results, i.e. around 475 Km/h on the deck. Garbage in and garbage out in both cases huh?

BTW: Concerning disappering, in your case we know the answer don't we? Permanently banned from a number of forums and as editor in Wikipedia. That sure is one hell of a story!

[Kurfürst]

Originally Posted by Holtzauge

I think people are aware by your modus operandi by now: If you don't like the message then discredit the messenger.

Nobody needs to discredit you.

Me "disappering" is for no more sinister reason than for working on a book project. Believe me it's much more satisfying than arguing about your doctored data or sparring with your mathematically challenged pal Crumpp!

.. but you seem to need to discredit others.

So if my Me109E data is so totally wrong

It is. It doesn't match tested results, does it?

[Holtzauge]

Originally Posted by Kurfürst

It is. It doesn't match tested results, does it?

I would love too see those test results.

Seems to me like you are confusing the calculated speed of the V15 prototype at 1.35 ata or the caveted Messerschmitt marketing material with actual test results. The only test results I've seen point to 466-475 Km/h.

You still have not answered the question: How do you account for HoHun's estimate of 475 Km/h?

[Al Schlageter]

Originally Posted by Holtzauge

I would love too see those test results.

Seems to me like you are confusing the calculated speed of the V15 prototype at 1.35 ata or the caveted Messerschmitt marketing material with actual test results. The only test results I've seen point to 466-475 Km/h.

You still have not answered the question: How do you account for HoHun's estimate of 475 Km/h?

And that is why we only see the V15 prototype data and not data for production Bf109Es.

[Kurfürst]

Originally Posted by Holtzauge

I would love too see those test results.

Seems to me like you are confusing the calculated speed of the V15 prototype at 1.35 ata

It takes a great deal of dishonesty and/or confusion to claim the V15a speeds are calculated.

"An Bf 109 V 15 a, der Mustermachine für die E-1-Serie, wurden die Geschwindigkeitsleistungen erflogen."

Can you translate the above please?

or the caveted Messerschmitt marketing material with actual test results.

Trouble is, Messerschmitt's type specification sheet ("marketing material") is the official specification for the aircraft, and was to be met by all similar Bf 109E in the Luftwaffe within +/- 5%.

The only test results I've seen point to 466-475 Km/h.

Well again it takes a great deal of dishonesty and/or confusion to claim not having seen flight test results, when the V15a flight tests have been posted in their full just a couple of pages back.

You still have not answered the question: How do you account for HoHun's estimate of 475 Km/h?

You should ask HoHun, but as you say: it's an estimate. For a different engine.

Curiously though, the French were hitting the exact same speeds at low levels (ca. 493 km/h) with their captured Bf 109E-3 as the Germans did with the E-1 (V15a)



It will be amusing when next time, you will claim you have not seen this either.

But, oh boy I forgot, you have your own charts.

Now let's see how speed figures claimed by British propaganda measured up to actual speed measurements... ooops, not very well it would seem! I am really looking forward to see a historically accurate Spitfire Mark V.

[Holtzauge]

I do read German and therefore I know the difference between what was flown and what was projected for the V15 prototype: "Blatt 6" shows about 485 Km/h for the FLOWN 1.3 ata value and the ESTMATED 500 Km/h value for "Geschwindigkeiten bei Garantierter Motorlesitung" 1.35 ata as a dashed line. So who is being dishonest now?

Concerning the French test it looks like very few data points and none at SL as I can tell so your claim that this supports the 500 Km/h seems a stretch.

So HoHuns and my calculations are for "a different engine" and can be discounted as "estimates"?. Quite interesting that this method of calculation works well with the Spitfire and also mirrors 466-475 km/h Rechlin test results for the Me109E SERIES aircraft no?

I see you added some Spitfire data now. I assume it's safe to bet that this is the absolute rock bottom worst data you were able to find on the Spit, right?

[Kurfürst]

Originally Posted by Holtzauge

I do read German and therefore I know the difference between what was flown and what was projected for the V15 prototype: "Blatt 6" shows about 485 Km/h for the FLOWN 1.3 ata value and the ESTMATED 500 Km/h value for "Geschwindigkeiten bei Garantierter Motorlesitung" 1.35 ata as a dashed line. So who is being dishonest now?

That's not really a question, it is still you (and you are doing it rather poorly as usual), so continue translating, maybe you are better at that - its funny you have not translated the first part isn't it.

2. Stoppflug.

Ergebnis: Erflogene Geschwindigkeit 493 km/h, auf Normaltag und Garantieleistung umgerechnete Geschwindigkeit 498 km/h im 0 m. Umrechnung siehe Blatt 5.

For those who do not wish to bother much with Holtzeuge's incoherent lies, here's the deal (as noted by the report clearly):

The aircraft (V15a), identical in all to series production E-1 flew low altitude speed trials on a four way track. The engine was bench tested as well (actually the ONLY test I am aware was this through), as was found to develop 45 PS less, and developed only 1.31ata in fligth instead of 1.35. Calibration flights were also made.

The 'raw' data collected (493 km/h at 0 m) was then converted for standard conditions: German Standard day atmospheric conditions, and normal engine power. The result was 498 km/h at 0m. The methods are clearly visible at the end of the report.

This is of course entirely normal, almost all Spitfire etc. tests for example do the same thing: correct the figures to normal boost ratings, and adjust for (British) Standard Day conditions. Otherwise, they would be useless for comparison...

Holtzeuge claim is basically because the flight tested data was converted (as usual) to standard conditions it needs to be dismissed because it's an 'estimate.'

Concerning the French test it looks like very few data points and none at SL as I can tell so your claim that this supports the 500 Km/h seems a stretch.

So HoHuns and my calculations are for "a different engine" and can be discounted as "estimates"?

Well they ARE estimates and they are for a different engine and different boost...

Quite interesting that this method of calculation works well with the Spitfire and also mirrors 466-475 km/h Rechlin test results for the Me109E SERIES aircraft no?

Nope, your calculations are not interesting at all.

I see you added some Spitfire data now. I assume it's safe to bet that this is the absolute rock bottom worst data you were able to find on the Spit, right?

Oh, not so finnicky about 'marketing brocheres' any longer, are we?

[MiG-3U]

Originally Posted by Holtzauge

Concerning the French test it looks like very few data points and none at SL as I can tell so your claim that this supports the 500 Km/h seems a stretch.

The French test shows about 494kmh at about 550m and and power chart gives about 1010ps at 550m, these values give 482kmh at sealevel with 990ps.

The outliers, like the sealevel speed in the V15a test, are usually caused by measurement errors. And given the fact that speeds match better with other tests at high altitude, it is probable that something is not right in the V15A measurements (error can be anything; failing device, typing error, calibration problem etc.).

[Al Schlageter]

Here is the document mentioned earlier.
http://www.kurfurst.org/Performance_...catter_web.jpg

13 a/c

4 below spec -5% > 31%
6 below mean > 46%
3 above mean > 23%

The average for all the a/c is well below the mean.

Applying this to the Bf109E would give an average speed of ~485kph.