Friday Update, February 10, 2012

[StG2_Winni]

Originally Posted by Varrattu

Hi Kwiatek,
please can you provide the source of that information?

Regards Varrattu

I'm not a specialist in those topics but you can read it here for example...

http://www.spitfireperformance.com/spit1vrs109e.html

They state the following:

"German data of the Me-109E shows top level speed ranging from 342 to 348 mph. Russian charts show top speed of the Me 109E-3 was 342 mph. French tests of a captured Me 109 returned maximum speeds ranging from 342 to 354 mph. (Il en résulte une incertitude sur les résultats: from estimated position error). 2a 2b 2c Swiss full power horizontal flight speeds of a Me 109 with DB 601 Aa averaged 348 mph at 16,404 ft. 2d US flight tests of an Me 109 E-3 operating at 1.3 ata obtained 290 mph at sea level and 339 mph at 17,500 feet. 2e Some German documents suggest that mature Me 109Es having DB 601As with improved superchargers may have achieved 354 mph at 16,404 ft. All figures without armoured windscreen, excepting Russian where condition is unknown. "

Does this help?

[Kwiatek]

Originally Posted by Varrattu

Hi Kwiatek,
please can you provide the source of that information?

Regards Varrattu

The most interesting documents are here:

http://kurfurst.org/#Emil

It is need to read it carefully.

I found for sure that German tested serial 109 E with Db601A at 1.3 Ata (990 PS) reached at the deck 467 km/h. ( radiator 1/4 open)

So with emergency 1-minut power at 1.4 Ata (1100 PS) 109 E would be even faster - about 15-20 km/h faster ----> so about 485 km/h at the deck (1/4 radiator open)

According to German manual for 109 E with Db601Aa at 1.45 Ata (1175 PS) it reached at the deck 500 km/h ( probably radiator closed looking at other 109 test like French and British also looking at climb times).


Of course it would be very short time to keep that speed beacause 1.4(601A)/1.45Ata(601Aa) could be keep only for 1-minute. Also 1.3/1.35 Ata was allowed only for 5-minutes.

Other test - French and British cofirmed German manual claims that 109 E could reach 570 km/h at 5.0km but with closed radiators - position of radiators could change speed of these planes at about 20-30 km/h depend of altitude.

For comparision Spitfire MK1 at +6 1/2 lbs (1/2 hour limit) reached at deck 455 km/h (283 mph) but with emergency +12 lbs (5-minutes limit) it reached 505 km/h.

[Insuber]

Originally Posted by Feathered_IV

Chivas, I wasn't thinking about the NG thing at all, more about trying to represent the entire pacific conflict from Pearl to the Home islands without fleshing out any particular area. Jumping later to the questionable content of 1946, then trying to give the Pacific Fighters treatment to Korea, before being reigned in to assume control of Cliffs, then zooming off on a tangent with the Moscow expansion. I just don't reckon that following through is one of his strengths. Maybe you feel that it is though.

I agree. Project management, or lack thereof, was the real issue of this series along the last 7 or 8 years.

[Varrattu]

Originally Posted by Kwiatek

According to German manual for 109 E with Db601Aa at 1.45 Ata (1175 PS) it reached at the deck 500 km/h ( probably radiator closed looking at other 109 test like French and British also looking at climb times).

The value 500 km/h is presumably taken from a Yugoslavian translation of one BF109. I cannot find any German Document with such data.

Regards Varrattu

[Kwiatek]

Originally Posted by Varrattu

The value 500 km/h is presumably taken from a Yugoslavian translation of one BF109. I cannot find any German Document with such data.

Regards Varrattu

Here is link to some data from manual:

http://kurfurst.org/Performance_test...chreibung.html

Here is data for V15a - German prototype of 109 E with Db601

http://kurfurst.org/Performance_test...15a_blatt6.jpg

Here is for German test of 109 E-3 Db601A at 1.3 Ata (1/4 radiator open)

http://kurfurst.org/Performance_test...MP16feb39.html

[SlipBall]

Originally Posted by Feathered_IV

Chivas, I wasn't thinking about the NG thing at all, more about trying to represent the entire pacific conflict from Pearl to the Home islands without fleshing out any particular area. Jumping later to the questionable content of 1946, then trying to give the Pacific Fighters treatment to Korea, before being reigned in to assume control of Cliffs, then zooming off on a tangent with the Moscow expansion. I just don't reckon that following through is one of his strengths. Maybe you feel that it is though.

There may be factors for 1c that we have little information about. I read that Russia has funding and tax breaks available. For game developers who design games that can teach the population about Russian history. We all recall the photo of Dmitry Medvedev on the control stick...so bom, who knows what's at play here.

[Kurfürst]

Originally Posted by Varrattu

The value 500 km/h is presumably taken from a Yugoslavian translation of one BF109. I cannot find any German Document with such data.

Regards Varrattu

Bf 109E was rated at 500 km/h at 1,35 ata, 570 km/h at altitude. Production tolerance was +/- 5%. The data is from the official German specification sheet of 1939 for the Bf 109E type.
(the yugoslavian manual you have seen is a translation of this document)


BAUBESCHREIBUNG für das FLUGZEUGMUSTER MESSERSCHMITT ME 109 mit DAIMLER-BENZ-MOTOR DB 601

Transcription of Part V, Performance datasheets, are found here:

http://www.kurfurst.org/Performance_...chreibung.html

The relevant speed curve from the above document:



The current Bf 109E is way too slow, it does about 460 km/h at 1,35ata, and 470 or so at 1,45 ata. [/u]It should do 500 km/h at 1,35ata (1015 HP).[/u]

It should do more than 500 km/h at 1.45ata (1175 HP), obviously. Power requirements increase on the cube for speed, so that means with +15.7% power, you will get around +5% speed, or about 525 km/h at 1.45 ata.

In the below actual flight trial, 498 km/h was achieved with the Bf 109E-1 prototype, the was identical to the serial production airplane in equipment etc (the engine was not developing full power at the tests, and achieved 493 km/h. They have corrected the figures for full nominal power at 1.35ata)

http://www.kurfurst.org/Performance_...w_109V15a.html

[Kwiatek]

I really doubt Kurfust that any serial 109 E could do above 500 km/h at the deck - in such case it would be equal or faster then 109 F.

Most German data for serial 109 E Db 601 A at 1.3 Ata ( 1/4 radiator open) claim 460-467 km/h ( 5-minut combat power). I think it is very beliveable result (confirmed e.x. by Swiss test and other data). Of course 109 E at 1-minut emergency power 1.4/1.45 Ata will be faster at about 15-20 km/h (with radiator closed little more).

Originally Posted by Kwiatek

I really doubt Kurfust that any serial 109 E could do above 500 km/h at the deck - in such case it would be equal or faster then 109 F.

This.
BTW Anybody tested Spit Ia on the deck? It should go up to 583 kph and I think it doesnt. Usually, I have a hard time catching an Emils at full speed on the deck. Btw, Spit IIa should be a bit slower on the deck than Spit Ia (570kph) but with better climb rate. Is it in the game? I think its much faster than anything....But I agree that Emil should probably do about 550 on the deck.

[Kurfürst]

Originally Posted by Kwiatek

I really doubt Kurfust that any serial 109 E could do above 500 km/h at the deck - in such case it would be equal or faster then 109 F.

Well it did 498 km/h at 1,35 ata, or 1018 HP measured in test.. why do you think, that at WEP (W button, 1,45ata, which produced 1175 PS on the 601Aa), that the extra 150 HP would yield no more than 2 km/h? Math simply suggest that an extra 150 HP will yield around 520-525.

Yes I agree that being as fast as the early F on the deck seems strange at first, but when you think it over, the F has a different (smaller diameter prop), that can easily result in +/-10 km difference alone. The G-14/AS, as per the book, was something like 8 km/h slower on the deck than the G-14 with the same horsepower (on the deck), but with a different prop.

On the other hand, on the E the 1.45ata rating of 1175 PS was really a short one minute burst, presumably intended for bombers taking off at heavy loads (He 111P!), while the 109F it was a full 5-minute rating. And of course the 109F is much faster at altitude, probably partially down to the new prop..

And of course the Spit I was also faster at the deck at than the early Spit V, so, I guess its just normal that "newer" just doesnt translate to "better" in every performance aspect.

Most German data for serial 109 E Db 601 A at 1.3 Ata ( 1/4 radiator open) claim 460-467 km/h ( 5-minut combat power).

Are you referring the Emil tests of the 17xx serial no. airplanes? In those case the point of the trial was to measure the difference if the MG FFs are mounted/not mounted, and if the slats are filled/not filled. The only relevant data to the tests makers was the relative difference in perfomance, because it probably allowed them to asses the invididual drag of these items (which turned out to be marginal).

And, in both trials it is noted that the speeds are not corrected for the nominal engine outputs (which they are in the tests I have posted), so they may understate the actual speeds if the engine was not running at its rated power (which was the case in the test I posted, where the E-1 did 493/498 km/h due to being down in power)

I think it is very beliveable result (confirmed e.x. by Swiss test and other data).

I strongly believe that the Swiss test show operation of the engine at the high altitude supercharger speed (ie. 2nd speed, bad for low level). If you compare to the E-1 trial I posted, you will notice the Swiss got very similiar results as the Germans using the Hoehenlader (2nd supercharger speed). So the Swiss tests IMO underline the validity of the 2 German trials I posted (showing 498-500 km/h).

It makes sense since the Swiss test is not a performance trial, in a sense they wanting to know what are the specs of the plane, but a comparison of top speed with three completely different propellers. Same reasoning as just above.

Of course 109 E at 1-minut emergency power 1.4/1.45 Ata will be faster at about 15-20 km/h (with radiator closed little more).

I think its beyond doubt that the correct low level rating for the 109E at 1.35ata is 500 km/h. This is what we have without the W button at full throttle.

There is the German test showing this, and btw, this is what is the OFFICIAL german spec for the plane, 500 km/h at SL.

Of course individual planes may have been slower - or faster, hence the +/- 5 % tolerance. Of course Hurris and Spits are neither modelled after the worst flight tests results either, so why would be 109s? They should be modelled after the nominal specs, like Spits and Hurris.

The 1.45 Ata speeds can be pondered on, but it seems we agree that the extra speed is worth about 15 - 25 km/h. Its a pretty good guess, becuase the math ruling it is simple. This should be simply added to the figure we know for certain, 500 km/h.