Friday Update, February 10, 2012

[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.

[Kurfürst]

French trials at ca. 980 Hgmm. Works out as ca. 1.3ata (we have 1.35ata engined model, which has a bit more power)



Its seems the French measured about 487 km/h at ca. 250 m with 1.3ata on a E-3.

[Varrattu]

I'm sorry, I do not find any original German manual / document where a Bf 109E was rated at 500 km/h (1,35 ata) at Sea Level.

Are those 500km/h at Sea Level mean TRUE AIRSPEED or Indicated AIRSPEED?

Regards Varrattu

[Kurfürst]

Originally Posted by Varrattu

I'm sorry, I do not find any original German manual / document where a Bf 109E was rated at 500 km/h (1,35 ata) at Sea Level.

See post no. 287.

BAUBESCHREIBUNG für das FLUGZEUGMUSTER MESSERSCHMITT ME 109 mit DAIMLER-BENZ-MOTOR DB 601
/ Type sheet for the aircraft model Me 109 with DB 601 /


V. L E I S T U N G S B L Ä T T E R.

D a t e n b l a t t Me 109.


A b m e s s u n g e n: / dimensions /

Spannweite 9,90 m
Gesamtlänge 8,76 m
Grösste Höhe 2,45 m
Flügelfläche 16,40 m

G e w i c h t e:

Zelle 650 kg
Triebwerk 1075 "
Ständige Ausrüstung 85 "
Zusätliche Ausrüstung 200 "
Rüstgewicht 2010 kg
Zuladung 530 kg
Fluggewicht 2540 kg

Bem.: Bei den Gewichten ist eine Toleranz von +/- 3% vorzusehen.



B e t r i e b s s t o f f:


Kraftstoff 400 l = 303 kg
Öl 30 l = 27 kg



M o t o r l e i s t u n g: / engine performance /


1) Nennleistung 1100 PS in 3700 m Höhe
bei 2400 U/Min.
(5 min. Kurzleistung in 3700 m Höhe)

Erhöhte Dauerleistung 1050 PS in 4100 m Höhe
bei 2400 U/min
(30 Min.)

Dauerleistung 1000 PS in 4500 m Höhe

Sparsame Dauerleistung 970 PS in 3700 m Höhe
Bei 2250 U/Min.

2) Startleistung 1175 PS in 0 m Höhe
(zulässige Dauer 1 Min.)
bei 2500 U/Min.

3) Bodenleistung 1015 PS in 0 m Höhe
Kurzleistung (5 Min. Dauer)
bei 2400 U/Min.

Erhöhte Dauerleistung 950 PS in 0 m Höhe
(zulässige Dauer 30 Min.)
bei 2300 U/Min.

Dauerleistung 860 PS in 0 m Höhe
bei 2200 U/Min.

4) Schmierstoffverbrauch 5 - 8 g/PSh
je nach Drehzahl und Flughöhe

5) Kraftstoffverbrauch

Erhöhte Kurzleistung in 0 m Höhe = 250 g/PSh + 20 g/PSh
(zul. Dauer 1 Min.)

Kurzleistung in 0 m Höhe = 220 g/PSh + 12 g/PSh
(zul. Dauer 5 Min.)

Erhöhte Dauerleistung in 0 m Höhe = 220 g/PSh + 12 g/PSh
(zul. Dauer 30 Min.)

Dauerleistung in 0 m Höhe = 220 g/PSh + 12 g/PSh
(dauerend.)

Kurzleistung in 3700 m Höhe = 220 g/PSh + 12 g/PSh
(zul. Dauer 5 Min.)

Erhöhte Dauerleistung in 4100 m Höhe = 220 g/PSh + 12 g/PSh
(zul. Dauer 30 Min.)

Dauerleistung in 4500 m Höhe = 220 g/PSh + 12 g/PSh
(dauerend.)

Spars. Dauerflug in 3700 m Höhe = 210 g/PSh + 12 g/PSh
(dauerend.)



Flugdauer. / flight endurance /


Die Flugdauer bei Vollgasflug beträgt 1,1 h in 6000 m.
Bei entsprechender Drosselung erhöht sich die Flugzeit bis
auf zwei Stunden.


G e s c w i n d i g k e i t s - L e i s t u n g e n: / speed performance /


Höchtsgeschwindigeit in 0 m 500 km/h
in 1000 m 510 "
in 2000 m 530 "
in 3000 m 540 "
in 4000 m 555 "
in 5000 m 570 "
in 6000 m 565 km/h
in 7000 m 560 km/h




Bei den Geschwindigkeiten ist eine Toleranz von +/- 5 % vor-
zusehen. Die Leistungen sind auf Cina-Temperatur gerechnet.



S t e i g z e i t e n. / climb times /


Steigzeit auf 1000 m 1,0 Minuten
auf 2000 m 1,9 "
auf 3000 m 3,0 "
auf 4000 m 3,8 "
auf 5000 m 4,9 "
auf 6000 m 6,3 "



Bei den Steigzeiten ist eine Toleranz von +/- 8 % vorzusehen.
Leistungen sind auf Cine-Temperatur gerechnet.


Dienstgipfelhöhe. / service ceiling /

Die Dienstgipfelhöhe beträgt bei voller Ausrüstung 11 000 m.


Engste Kurvenradien. / tightest turn radius /


Im Luftkampf betragen die engsten Kurvenradien ohne
Ausschlag der Landeklappen / without flaps /

in 0 m Höhe 170 m.
in 6000 m Höhe 320 m.

Mit Klappenausschlag sind die engsten Kurvenradien / with flaps /

in 0 m Höhe 125 m.
in 6000 m Höhe 230 m.


Start- und Landestrecken. / take off-landing distance /


Bei dem vollen Fluggewicht von 2540 kg beträgt die Startstrecke
bis zu einer Höh von 20 m 420 m.

Die Landestrecke vom Aufsetzen bis zum Stillstand beträgt 300 m.

Die Landestrecke aus einer Höhe von 20 m bis zum Stillstand beträgt 485 m.

Die Landegeschwindigkeit beträgt 125 km/h.

Are those 500km/h at Sea Level mean TRUE AIRSPEED or Indicated AIRSPEED?

Regards Varrattu

True Air Speed.

[Insuber]

Originally Posted by Varrattu

Are those 500km/h at Sea Level mean TRUE AIRSPEED or Indicated AIRSPEED?

Regards Varrattu

Maybe I misunderstand your question, but TAS=IAS at s.l.

Cheers,
Ins

even the spitfireperformance.com says BF109E should do around 560 max at level

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

IAS and TAS almost the same at sea level.

@Kurfurst - I will test the Emils top level speed tonight and will post results here.....I doubt its only 470 kmh

[Kurfürst]

Originally Posted by Tvrdi

even the spitfireperformance.com says BF109E should do around 560 max at level

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

IAS and TAS almost the same at sea level.

@Kurfurst - I will test the Emils top level speed tonight and will post results here.....I doubt its only 470 kmh

I measured 460-470 near SL - as noted, it should be 500..

I did not test top speed (ie. at 5000m, where it should reach 570 kph TAS) because its impossible to test high altitude speed with reasonable accuracy. COD only shows IAS speed even in cocpit off mode, and the TAS/IAS conversion creates a too large margin of error to get accurate enough results, to draw any valid conclusions IMHO.

[Varrattu]

@Kurfürst

Thank you for the detailed message.

With a little patience it is possible to reach such horizontal speeds at sea level with the BF109E-iL2CoD ... ...

By the way: the BF109E-iL2CoD is fitted with a 1200 PS machine.

Regards Varrattu