The bf109f-4 need to know more

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thedab

Airman 1st Class
120
12
Apr 21, 2013
norwich
Hi I would like to know the true performance of the 109f-4,as the performancn data which i seen is bit limited
 
Hello thedab,
for a long time I had the same idea in my mind. Now I had the conclusion for me that the 1.42 ata for the 1350 PS never was realeased. In my opinion the stated performance with 1200 PS at 1,3 ata for the F-4 was reasonable.

Detlev
 
Table available here states 670 km/h, on 1,42 ata (Start und Notleistung) . Dated February 1942. This table lists performance on 'Steig und Kampfleistung' (1,30 ata), 635 km/h being the best value, achieved at 6 km. To the best of my knowledge, the Notlesitung was allowed during the winter of 1941/42.
For the 670 km/h there is statement that value was not corrected, either for compressibility, and that real maximum speed should be ~655 km/h.
 
Hello tomo pauk,
this are only calculated datas. With 1.42 ata the F-4 would be a very great performer for this time, especially in climb. But in my opinion this was never realised for frontline service. I imagine when the frontline pilots in the end of 1942 must exchange their 1350 PS F-4 for the heavier and only 1320 PS rated G, a great outcry must be happen. But this dont occur. The pilots stated only that the new G-model was not much of an improvement, and this is in accordance with the performence-datas of both models with 1,3 ata.

Detlev
 
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Hello, Detlev,
The F-4 is, as it seems, a very mysterious bird :) The flight test data seem like non-existent. The manual, from February 1942, does not state the ban on Notlesitung, ditto for the power chart. In this forum the 670 km/h value was stated as being not corrected, but we do not have any 'hard' data about that.
How much heavier was the G-1 or G-2 vs. the F-4? The early Gustavs were far more streamlined than, say, G-6 (HMG bulges, fixed tailwheel, bigger tires), and lighter. The G-2 was tested, on 'Steig und Kampflesitung', as being capable for comfortable 660+ km/h, ie. almost 30 km/h faster than F-4 on the same power setting. We might remember that 'Notleistung' was the 5 min rating, vs. the 30 min 'Steig und Kampflesitung', so the G-2 will still climb and/or fight at max rate/speed further 25 minutes after the F-4 is forced to throttle back from 'Notleistung'.
The DB-605A does make more power above 5200m on 'St. Kmpf. leistung' than DB-601E on Notleistung (and it can do it 6 times as long), and some 5-15% more on same power setting. Seems to me that pilots did not have anything to complain about?
 
The Gustavs were released with 1475 PS, only during their service a problem with the engine system was discovered and leading to the Notleistung ban. Pilots were not happy about the power loss but happy about the increased reliability. Too late for H-J Marseille though.
 
Chart I made for reference I while back. Sorry about the imperial - my file is mostly British aircraft.

f4s.jpg


EDIT: slightly larger
http://www.ww2aircraft.net/forum/at...55d1367169200-bf109f-4-need-know-more-f4s.jpg
 
Hello tomo pauk,
this are only calculated datas. With 1.42 ata the F-4 would be a very great performer for this time, especially in climb. But in my opinion this was never realised for frontline service. I imagine when the frontline pilots in the end of 1942 must exchange their 1350 PS F-4 for the heavier and only 1320 PS rated G, a great outcry must be happen. But this dont occur. The pilots stated only that the new G-model was not much of an improvement, and this is in accordance with the performence-datas of both models with 1,3 ata.

Detlev

i read an interview from a former LW ace...it may have been Rall...who said he preferred the F model over all the others.
 
Probably because it was pleasant to fly.

That doesn't necessarily mean he would prefer Me-109F4 over Me-109K when attacking B-17s during 1945. Brute force can be useful in combat and that's what late war Me-109s had which 1941 Me-109F didn't have.
 
found it! it was Franz Stigler... got this from his interview.

Now, the first plane you flew in the Luftwaffe was the 109?

Yeah…

Which was the first Model was it?

F

How did you like it?

I liked it a more than any other one…this is an F model.

(Franz points back to the massive painting behind me)

Cool…it has the tropical filter as well.

Yeah…and where is a G…(Franz looks around date the multitude of painting and photographs)… that is a G model here…(Franz points to another smaller painting, again featuring a G-6 in his original colours)…that's the last 109 I was flying.
The last one you flew was a G?

Yeah…actually it was a K model, but uh…we used it as a G model, you know…and then I was a…a pilot for the 262 also.


ok so what does it mean they used the K as a G model?? they used it more as a fighter rather than a bomber intercept or visa versa?? i am guessing he loved the F model because of the way it handled. from what i understand it was the most nimble of the 109 line.
 
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Hi Tomo

I agree with most of your writings there. Just a couple of remarks.

The 670km/h figure for the F-4 (notleistung) was in fact corrected and is the final top speed figure. Supported by the "hard" data we all like to see. Pls see GL/A-Rü IA This particular issue also asserted by kurfurst at Kurfürst - Mtt. AG. Datenblatt, Me 109 G - 1. Ausführung

In the GL/A-Rü IA document you will also find some very interesting "hard" data supporting the 700km/h top speed figure for the G-1 that I mentioned before and that no one at this site including you liked to believe. There is also in existence several flight test documents from Rechlin (before the ban of notleistung for the DB605) supporting the high G-1 speed. Ask M Rausch if you want to see them.
 
Hi, 69TA,
People can find the " GL/A-Rü IA" document (or just a part of it?) here.
We can take a look at specifications of the G-1 listed there. It has one MG-131 as engine-MG (intended to replace 2 fuselage MG-17s?), two MG-151 in the wings and makes 700 km/h? Since there was never a G-1 with such a weapon set-up, it can point us that such values were just projected ones.
The document also lists the F-4 with 2 x MG-131 (as the alternative for the LMGs?) in mid-1942 - again, no such thing was in production ever. And no speed loss was attributed for such an F-4.

Since the document is a review of Axis planes in use in June 1942, it is by no means a primary document.

There is also in existence several flight test documents from Rechlin (before the ban of notleistung for the DB605) supporting the high G-1 speed.

What would be the most expedient way to do that?
 
Hi, 69TA,
It has one MG-131 as engine-MG (intended to replace 2 fuselage MG-17s?), two MG-151 in the wings and makes 700 km/h? Since there was never a G-1 with such a weapon set-up, it can point us that such values were just projected ones.
Do you mean that some G-1's never came with MG151's? Because pilot log books note that some G-1 flown by I./JG 1 carried the underwing 20 mm MG 151/20 cannon gondolas. I apologize if this isn't what you meant.
 
No need to apologize.
The G-1 is listed in that document as being armed with fixed (so, no Rustsatz) wing cannons regularly.
 
Tomo.

Those who really want to know can find the GL/A-Rü IA document in the Bama archives in Frieburg. I did. It is an original document issued June 1 , 1942. Don´t understand your comment about it not being a primary document there, sorry.
If you want to be serious, yYou cannot just disregard the speed figures mentioned in that document.
It is indeed a summary document and as such, it mentions different kinds of armament and other features of the aircrafts relevant at that point in time. But that has nothing to do with the speed capabilities mentioned.
 
I'd really love to get the document myself - it's a book actually?
The primary document is the flight test report, the book that lists planes would not be the primary document. Similar thing can be shown for eg. different charts for the P-63 and F6F, emanating from manufacturers - we have flight tests that quickly show that manufacturer's figures are overly optimistic.

It is indeed a summary document and as such, it mentions different kinds of armament and other features of the aircrafts relevant at that point in time. But that has nothing to do with the speed capabilities mentioned.
The 2 x 20mm in wings are not the "different kinds of armament" available, neither the Rustsatz/Gondelnwaffe. Their position is simply listed as 'Flugel', ie 'Wing (mounted)' - fixed, in other words. We know very well that such G-1 never existed, and it would be even less able to do 700 km/h. The primary document would never made such error.

At the Kurfurst's site one can find charts showing the G-1 making around 650 km/h on Steig Kampfleistung (~1250 PS), here for example. We should believe that extra 100 PS (+8%) should propel the G-1 some 50 km/h (+8%)? German engineers were good, yet their products also obeyed the laws of physics.
 
There is a graph on beim zeugmeister site for 700 kph G-1. It also notes the figures are for Notleistung, and are calculated based on F-4 figures. I believe these may be preliminary figures, since they also planned some improvement for G series that did not realize in end - for example, wheel well covers, that is why the plane had those square wheel bays as opposed to the rounded ones on the F... according to drag document on kurfurst site, wheel well doors mounted to +10 kph alone. So take a 670 kph F-4, add 10 kph, and some extra 100-150 PS at altitude and 700 kph does start to sound reasonable (based on a 670 kph F-4). I think it was a big missed opportunity. Otherwise why bother with the G and the 605 at all?

Note document. http://www.beim-zeugmeister.de/zeugmeister/index.php?id=13&L=1

It says all speeds are notleistung. 109F is 670 erflogen (flight tested), 109G is 730, calculated. At that time many improvements were foreseen for 109G...

I think the 2x20 mm simply notes the gondola option, and is simply a typo during copying the F-4 cell contents. Often there is in old documents such mistake... when you have actually type 50+ pages and still take your nazi girlfriend to the movies it happens.. ;) Also in the ammo note it also has 200 rounds, like 151/20 of F. In fact the G weapons are exactly same as F-4 (look at number of rounds). They note there too MG 131, which probably means upgrade is possible (it was, in fact Galland already had his custom 109F fitted with cowl MG 131s).
 
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