Bf 109 G range and endurance

[gripen]

Originally posted by phookat
Hmm, OK.  Still don't see how this would be so hard.  You could do it with a fuel flow meter, and if they didn't have those you could just fly until the tanks were almost empty a few times (to take into account wind etc).  Even if it was hard presumably they did it anyway, but perhaps not with captured planes.

Well, just look Australian tests, really lot of flying at various altitudes and power settings is required even with the fuel flow meter and final results are not known before calculations. It's very unlikely that they did such testing with a captured plane in the field conditions.

Originally posted by phookat
Yes, I did not realize you were quoting a captured report.  In that case clearly there was no theoretical calculation involved.

Why a captured report should exclude theoretical calculations? What if they used captured engine documentation to calculate range and endurance? Basicly all performance aspects must be calculated in some degree (corrections etc.) and calculations are possible in the field conditions without special equipment if some basic data is available.
 

Originally posted by phookat
Presumably they didn't--but I would imagine that the Germans *did*, to come up with that documentation.

Yes, the Germans made some documentation, as an example look the data Isegrim just posted; is there real test data? Basicly Isegrim continoysly selects data which makes his beloved Messerschmitt look good.

FAF tested engine settings according to documentation and found out that at low power settings engine run roughly and exhaust gases tended enter cockpit. Most practical cruise setting at non combat conditions was around 0,9-1,0ata and 2100rpm, at combat conditions they used 1,15ata and 2300rpm.

Originally posted by phookat
Tests tend to eliminate variables, while anecdotes create them.  I still maintain it's best to compare test to test.  Of course test conditions may be different and results have to be normalized for comparison, but for modeling purposes each test combined with its conditions is IMO far more reliable than other information.

I'm not using anecdotes but FAF test data and I'm  quoting it pretty much directly, some of that is published in the Jukka Raunio's "Lentäjän Näkökulma II". In the case of the Autralian test on the Spitfire VIII, we can be sure that it's real tested data but can we be sure that Isegrim's data is real tested stuff?

gripen

[Angus]

Nice data Issie.
Fact remains fact, fact IS data. For the record, what Nashwan and especially Gripen bring up on these boards, I regard as quite reliable indeed.

Speaking of a trop 109, I know that 109G's and presumably F's from Bizerta operated as far as the City of Algiers, and easily over Annaba (Bone)
Flipping the coin, imagine me trying to prove from data that they could not have been there.

But they were.


I do not recall drop tanks being mentioned.

Oh, for a change, look at the O'club thread about the Warshaw uprising. It evolved nicely into a fight about what the German army could have done at Stalingrad, had their armed forces and LW not also been tied up in N Africa.
Just crossed my mind to mention it, for finally there could possibly be something we actually agree about



Regards


Angus

[VO101_Isegrim]

Lot`s of talking here, Gripen, ZERO amount of facts.

Lot`s of reference to reports that nobody else than you have seen, as usual, but nobody can see the reports themselves.

Lot`s of claims going in and out, ENDLESS repeating of how 'merlin engined mossies and mustangs ripped the 109s apart', how 'the Spitfire and 109 had practically the same range'. and 'the MkVIII having double the range', and 'it must be calculation', and 'it`s outright impossible to repeat the same numbers in RL'. Rather morbid (or naive) in the same thread with URLs to reports that state the exact opposite.

Every time there`s a 109 thread, you do the same and desperately try to disprove, disregard and dismiss anything good on the 109, at the same time, doing nothing else than repeating the same crap of yours.

You are hopelessly outclassed in the ability of back up the statements made with credible sources and data. As long as you can`t do anything else but question every single source that disproves you, yet unable to provide anything at all to support your little crusade, your words worth as much as farting in a tornado.

[Angus]

Now come on, stop it Issie, and answer my post instead

[VO101_Isegrim]

Originally posted by Angus
Nice data Issie.
Fact remains fact, fact IS data. For the record, what Nashwan and especially Gripen bring up on these boards, I regard as quite reliable indeed.

Hate to be negative, but if I look it up factually, Nashwan brought up a part of the MkVIII report (posted away from the source to ensure the rest cannot be viewed by others, only the part fitting in Nashwan`s mindset) which`s other parts I posted later and it states 740miles range for the Mk8 on internal 120 gallon, same as the 109G on 85 gallon, so this questions Naswhan`s claims about similiar mileage on the two aircraft, not to speak the direct evidence available for the engines themselves, which in every time show considerably higher consumption on the Merlin`s side, making equal mileage quite simply impossible. He then projects his own internal working, being unable to put up with Spitties were not best in everything, and states I only put up the thread to show the Spitties defiency with range (which regardless of the 109, true and is accepted by 99% of the people) and that 109s were better (they were;) - fact is if somone looks up the thread start, Spits/Merlins are not mentioned at all until Karnak`s post:


"The 755 miles sounds entirely reasonable to me for a short range fighter witha drop tank. It is pretty close to the Spitfire Mk IX's 850 miles.

The 1,250 miles seems, um, highly suspect. Very highly suspect. The DB605 would have had to have been insanely more fuel efficient than the RR Merlin in order for that to be possible."


To which I replied it was true, the DB 605 was more fuel efficient (numbers were shown) and the 109 had less drag on the top of that, I think few here would argue.

That one hit Nashwan in the nerve, and he started selective qouting from the Mk VIII test, to prove the His Holy Elliptical Winged Cow can do just as good, and even better than that of course. Now, the problem is that the same report states 740 miles with 120 gallons fuel, the 109G report shows 755 miles w. 88 gallons of fuel.. ever since he tries to turn this upside down, aiming at my person in desperation `cos he can`t do nothing about my facts...


As for Gripen, he largely broughts up his own mindset, little more. Fact, no single document, or reference from Gripen yet on this thread. He just repeats his own statements which I have no reason to trust, knowing him, and knowing his habit of not being able to support his claims with hard evidence.

He repeats that the report is just silly, theroretical, can`t be trusted. Silly, theroretical, can`t be trusted. Silly, theroretical, can`t be trusted. Silly, theroretical, can`t be trusted. Engine fuel consumptions irrevelant, Merlin engined Mossies Mustangs were over German bases. Engine fuel consumptions irrevelant, Merlin engined Mossies Mustangs were over German bases.Merlin engined Mossies Mustangs were over German bases and shoot down 109Ks en masse (I`d invite Grippy to show us those loss reports:). The British didn`t tested anything, it`s just calculations.  The British didn`t tested anything, it`s just calculations.  The British didn`t tested anything, it`s just calculations, testing is very hard and difficult and quite impossible especially if there`s a report showing 1200+ miles range for the 109. Can`t use that low engine powers anyway, just can`t. Can`t use that low engine powers anyway, we don`t even know them, he says, but we know it just can`t be used (same RPMs are listed in MkVIII report, no problem to use those of course:). Finn Reports Only Gripen Seen But For Some Odd Reason Can`t Show Us say it`s just 1-1.5 hours of endurance. Finn Reports Only Gripen Seen But For Some Odd Reason Can`t Show Us say it`s just 1 hour of endurance (thinking about it, with 400 liter internal, that means 400 lit/h consumption, running at 100% power all the time...)

And so on. Fairly tales, and they really look stupid if you compile them.

Oh, for a change, look at the O'club thread about the Warshaw uprising. It evolved nicely into a fight about what the German army could have done at Stalingrad, had their armed forces and LW not also been tied up in N Africa.
Just crossed my mind to mention it, for finally there could possibly be something we actually agree about

[/B]

Uhm, anyway I try it I can`t think freeing up the DAK to Stalingrad would make lot`s of difference. At the time the 6th Army was encircled, it was a rather small force, a drop in the ocean compared to the Russian front numbers. Before El-Alamein, they had some 20 000 men and 250 tanks (it was just a Korps, you see), and they lost almost all tanks but rather little manpower in the battle. Perhaps it`s more correct to say the reinforments that were sent into Tunisia were wasted, but on the other hand, when those were sent the 6th Army already surrendered/was beyond hope.

[Angus]

Not what I meant.
My point there is that if there had been NO N-African Campaign, then what?

[gripen]

Dear Isegrim,
May I ask you when I have used source which no-one else has seen?

Regarding Mustangs ripping Bf 109Ks; I have noticed that you love such text...

Guppy35,
I checked Morgan&Shacklady today and found following (p.286):

"MT818 (Furlong 20-7-44) First Mk VIII with 75 gallon fuel tank behind pilot. Unstable but not viciously so. MT818 (Furlong 27-7). It is estimated that aeroplane becomes stable after 37 gallons have been used from the rear tank. MT818 (Furlong 15-8). Long range Spitfire. Now has standard oil tank giving standard non-bulged bottom cowling. Flown with all tanks full. MT818 (Furlong). It is considered that the aeroplane might possibly be accepted by Boscombe Down. Deletion of the PRU tank and subsequent fitting of non-bulged cowling has improved stability."

Apparently some Spitfire VIIIs got rear fuselage tank but I have no idea if any VIII with such tank reached service.

gripen

[phookat]

Originally posted by Angus
I disagree. There is a stage between those two.
This is just about aircraft frequently getting to a certain location and back under different cirkumstances. If your calculations say this is not possible, they must be wrong, for they are calculations against several actual occurances.

No.  The test does not disprove the RL experience or vice versa, because of the fact that they may have been taken under different conditions.  You do not know if the circumstances of your anecdotal flights were ever the same as the test, because they were not recorded.  You are simply guessing.  For modeling purposes we need the conditions documented.  Tests do this as much as possible.  Anecdotes don't.

Furthermore, I would like to see your response to HoHun's post above.

Another way of looking at this.  If the test data was so ridiculously at odds with reality, don't you think the testers would have noticed?  "You know, old boy, I believe you've substituted furlongs for cubits here, otherwise all our Spitfires would be falling into the Channel."

Originally posted by Angus
Range is in this sence a much more absolute thing than ever more flexible things as turning for instance.

True, it is not as subject to opinion.  However, it is certainly subject to circumstances.

[HoHun]

Hi Isegrim,

>First, the excerpt of a British Middle East report on a captured 109G-2/trop in poor condition (malfunctioning radiator control, .50 damage from P-40, tropical filter installed).



I've just run the numbers, and I'd say the figures for the Messerschmitt are realistic.

Though I can't reproduce the exact combinations of speed, altitude and endurance and the RAF obviously didn't use the documented DB605A power settings, my mileage doesn't vary much if I plug in the official data.

Note that the range of the Me 109G on Maximum Continuous and that of the Spitfire XVI on Most Economical is very close (as is speed - the Spitfire's 210 mph must be IAS, so it's 296 mph TAS vs. Me 109's 315 mph).

From the British chart, it's obvious that they reduced power to a very, very low figure to get the maximum range - just look at the long endurance they're getting out of the internal fuel tank!

For that kind of power, the range provided by the table is entirely credible. (Remember that the British - even before the Japanese - were the pioneers of long-range flying, so they certainly knew the techniques.)

However, I have some doubts about the Spitfire numbers. It simply looks as if what's labeled "Most Economical" on the chart should really be labeled "Maximum Economical" (which is the maximum power that can be considered remotely economic, not the most economical power :-)

For the Spitfire XIV, I can confirm that directly from the Pilot's Notes, which list 276 mph as the highest, least economical cruising speed at 20000 ft with about 3.75 mpg, compared to an optimum of 5.3 mpg at just 190 mph IAS.

For the Spitfire XVI, I suspect it's the same because the cruise speed given is almost as high as the Me 109's at Maximum Economical. Similar to the Me 109, the Spitfire XVI's range should benefit from reduced speed, too.

Unfortunately, the Spitfire IX, XI, XVI's Pilot's Notes don't provide a range graph like the Spitfire XIV's, but I'd say the Spitfire's optimum range was longer than the RAF comparison chart makes it appear.

Anyway, good research, and an interesting topic! :-)

Regards,

Henning (HoHun)

[Nashwan]

Hate to be negative, but if I look it up factually, Nashwan brought up a part of the MkVIII report (posted away from the source to ensure the rest cannot be viewed by others, only the part fitting in Nashwan`s mindset)

Isegrim, I posted a page from the report, and told everyone where it came from.

From the Australian archives via Ring's site

I think most people here, including you, know where Ring's site is.

Now, you have posted part of a page from "a British intelligence report", without even telling us what the report is, let alone letting us see the rest of the report.

which`s other parts I posted later and it states 740miles range for the Mk8 on internal 120 gallon,

If you notice, it says "with 23 gallon 'allowance' ".

This page is not part of the fuel consumption report, it's an appendix to a single page summary of the features of the Spit VIII.

The actual report is quite clear:

That one hit Nashwan in the nerve, and he started selective qouting from the Mk VIII test, to prove the His Holy Elliptical Winged Cow can do just as good, and even better than that of course.

I posted the test results. They're the only results I've seen for the Merlin 66 engined Spit.

Now, the problem is that the same report states 740 miles with 120 gallons fuel,

No, it's not the same report. It's an appendix to a single sheet summary of the features of the Spit VIII, entitled Spitfire VIII, general description and performance. In fact, the page is:



As you can see, it makes reference to appendix I, which is the "summary" you've posted.

Notice that nowhere in the test does it refer to appendix I being included, it notes the consumption figures are to be found in the tables and graphs I've posted.

Also, the figures I've posted all state they are valid in standard atmosphere conditions. There is no note on what conditions the summary you would rather use is valid for, or whether it's based on tests, guess work, includes a large margin of error for safety, etc.

We have explicit tests under known conditions, we have a "brief summary" under unkown conditions, Isegrim chooses to rely on the latter.

[Nashwan]

I've just noticed that the figures Isegrim are relying on, in the "brief summary", are dated 24/10/43, the range tests that give higher figures are dated 28/03/44.

The figures Isegrim wants to use are not based on the tests, as they preceed the tests by many months. So not only don't we know the conditions they are relevant to (hot Australian conditions, perhaps, instead of standard atmosphere?), we have no idea if they are based on tests.

The doc in fact say wingspan is 40ft, which is the extended span, yet it claims it's fitted with a low altitude Merlin 66.

Guppy might know if the extended span VIII was ever fitted with a low alt Merlin 66, but I find it unlikely.

[phookat]

Originally posted by gripen
Well, just look Australian tests, really lot of flying at various altitudes and power settings is required even with the fuel flow meter and final results are not known before calculations. It's very unlikely that they did such testing with a captured plane in the field conditions.

Why a captured report should exclude theoretical calculations? What if they used captured engine documentation to calculate range and endurance? Basicly all performance aspects must be calculated in some degree (corrections etc.) and calculations are possible in the field conditions without special equipment if some basic data is available.

OK, we got two choices here.  These numbers come from either the Brits or the Huns.

If the Brits did it, then clearly the numbers came from real tests, since as you pointed out they didn't have the ability to do a theoretical calculation.  If the Huns did it, then it could be either theoretical or practical.

But why shouldn't it be a practical test?  Everyone else did it, including the Aussies as you mention above--despite whatever difficulty it entailed (which I still don't agree with but I can accept hypothetically).  Why not the Huns?

But given the possibility that it was theoretical, we should consider practical matters such as the exhaust fumes you mention (however I have some questions about that, see below).

Originally posted by gripen
FAF tested engine settings according to documentation and found out that at low power settings engine run roughly and exhaust gases tended enter cockpit.

This is interesting information.  Can you point me to the documents which describe this (in English if possible)?  Are there any documented tests of 109 pilots flying at such speeds?

[HoHun]

Hi Angus,

>230 km each way with perfect navigation. Then one has to think off unfavourable winds and combat situation.

Well, 230 km is for cruise at maximum continous, 10 min reserve at economical power and 10 min of combat at maximum power, and without the range covered during climb and letdown. It's really a realistic range.

The long-range Spitfire II with fixed 40 gallon underwing tank was used by No. 66, 118 and 152 Squadrons according to Alfred Price.

Regards,

Henning (HoHun)

[VO101_Isegrim]

Originally posted by Nashwan
I've just noticed that the figures Isegrim are relying on, in the "brief summary", are dated 24/10/43, the range tests that give higher figures are dated 28/03/44.

Yes, Nashwan, surround it with hordes of " " , maybe it will make it disappear.

Funny that the report he likes to use while ignoring all the others is titled :

BRIEF PERFORMANCE TRIALS OF SPITFIRE MK VIII AIRCRAFT
FUEL CONSUMPTION TRIALS

Apperantly, Nashwan`s 10 mph claim is only from a quick and rough testing with possibly not even the right equipment available for correct measurments, being hastily done with large margin of error.

The figures Isegrim wants to use are not based on the tests, as they preceed the tests by many months.
[/B]

Still, the official British words is that the Mk VIII`s range is 740 miles on 120 gallons internal fuel.

Mk LF IXs can do 434 miles, Mk F IX can do 450 miles according to the British documentation.

No way to come around that.


Every single book states the Spitfire had 430-450 miles on internal on 85 gallon.  including Spitfire the History, including these papers :

http://www.x-plane.org/users/isegrim/FvsF/Spitchart.jpg

With the same engine, and 50% more fuel, one would guess the range should be up 50% as well, from 450 to ca.700 miles.

It happens that the another report just states 740 miles on 120 gallon fuel, in perfect agreement.

Naswhan perhaps thinks the MkVIII had twice the mileage per gallon than the same engined Mk IX..

 So not only don't we know the conditions they are relevant to (hot Australian conditions, perhaps, instead of standard atmosphere?), we have no idea if they are based on tests.[/B]

'We'? Speak for yourself, perhaps then it would be more correct that you have no idea on many things.

Perhaps these papers are just wild guessings. Yes, this must the case, as they are in full agreement with every other British statement regarding Spitfire ranges.

The doc in fact say wingspan is 40ft, which is the extended span, yet it claims it's fitted with a low altitude Merlin 66.
[/B]

AH, those LIARS ! Don`t believe them, don`t believe a word!

Interesting theories, Nashwan.

Still, the problem with it there are hordes of sources, all showing no more than ~450 miles range for all Spitfire Marks, except the Mk VIII, which is shown at 740 miles range on internal fuel.



But, let`s give a chance to prove yourself, since you are so fond of telling everyone the Spitfire was the longest ranged, most heavily armed fighter of WW2, that outdived every other fighter, in not in tests, then in flyboy memoirs, that you come here in a 109G range thread, start trolling about those invincbile Spitties as usual, what was the range of the Mk IX and Mk VIII?


What do British papers tell about it ?
What does Spitfire the History tell about it ?
What do every single source tell about it ?
What do these archieve papers tell about it ?


http://www.x-plane.org/users/isegrim/FvsF/Spitchart.jpg
http://www.lanpartyworld.com/ww2/files/spit/8/109.jpg


I reckon they say 450 miles for the Mk IX, and 740 miles for the Mk VIII.

You disagree with them, and say they are all in error ?

Of course with 10mpg economy you claim to be possible, the MkVIII should have really no problem getting to Berlin. In fact, you seem to tell us the Mk VIII was as long ranged than the Mustang.

We all know Goering said when he first saw the first MkVIII over Berlin that they lost the air war. And I tell you, there were hordes of Mk VIIIs and MkIX screaming all over the German-Polish border.

[Nashwan]

Theories, Isegrim?

Not at all.

I've posted a range test on the Merlin 66 engined Spit.

It clearly shows up to 10 mpg at 20,000ft with a 90 gallon drop tank fitted.

You don't want to accept that figure, so you have posted various documents, none of them tests, none of them giving exact conditions, many of them not even stating what engine.

There's one set of test data, and it says 10 mpg. Get over it.

Every single book states the Spitfire had 430-450 miles on internal on 85 gallon.

I could ask with which engine, but instead I'll use one of your own quotes, from the very first post in this thread:

since there`s so many misunderstandings about that in the literature (most books state high-speed cruise ranges only).

What about posting the complete report you've extracted the 109 range figures from?  Can we see it all, please?