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Patch_whiner
10-16-2004, 05:56 AM
The Bf-109 has high fuel consumption in FB/AEP. Curiously in the original IL2, the Bf-109 had much lower consumption. You could fly the Bf-109 for quite a long time, even the Emil. With the introduction of FB all that changed. For an experiment I flew various aircraft over approx. 300 km. A Hurricane IIb used 110L a LaGG 3 260L, an A6M2 250L, an FW-190 A4 200L and a Spitfire IXe 160L €" I tried an Emil with full fuel (400L). The engine was virtually out of fuel as I touched down and used 375L. So an Emil has 2-3x the consumption of certain fighters. I can€t explain this. The DB-601 engine was presumably a very efficient unit, obviously if it is put in a poorly designed aircraft which is heavy an un-aerodynamic then consumption will be high. The Bf-109 could hardly be put in this category. The engine (according to data in the game) gives about 1050 hp, which is similar to the output of the finest V12 engines at that time. So it doesn€t have any big hp advantage which might explain the fuel consumption. The practice of BnZ is one which does incur high fuel usage, perhaps it is the large requirement for energy to climb quickly that is the cause of consumption. The low drag aerodynamics of a BnZ fighter, coupled with the efficient penetration an in-line engine gives should enable you to go far, not have a limited range. High revving engines sometimes have higher consumption, but the Emil revs to 2200 rpm at 100% throttle as opposed to a Spitfire Vb at 3000 rpm. If the DB-601 had a small capacity this might explain high consumption, but then small capacity engines often rev higher. All the following are incorrect:
1.The prop. was badly designed
2.Valve timing and lift were excessive causing less power and higher consumption
3.Although 400L is marked on the gauge the fuel tank was only 200L
4.1C Maddox programmers typed in the wrong figures for the Bf-109

So I am at a loss to explain why the Bf-109 drinks the way it does, it is the only fighter I know that uses 50L in 5 minutes of combat. It could be something simple or is it the result of many small factors. Maybe it is because the engine is always working close to its maximum output, unlike other larger engines working at lower levels compared to their maximum. Was the DB-601 like a racing engine that has high power but low torque?

PW

Vipez-
10-16-2004, 06:32 AM
Yep, fuel consumption in FB has allways been very wierd.. once again, its funny it only seems to concern german planes.. for example 109 E-7 and 109 G-2, they consume their full tank much faster than, lets say 109 F-2 / F-4 .. (they even have the same range).. they have same range, and F-4 stays in the air much longer than G-2 and Emils.

Now when you look at russian planes, for example I-16 (about same range, 485 km) it does not seem to consume any fuel at all compared to german planes (except when you get a fuel leak) .. FW-190 is the wierdest of all, particularly 190 A-5 and A-6.. a-6 is esspecially fast to consume its full tank very fast, same range as for example, Lagg-3 ( lagg 3, 870 km, fw190 a-6 about 900 kilometers) , and compare how much faster A-6 uses its full tank compared to the Lagg3.. http://forums.ubi.com/images/smilies/1072.gif

Though i do think Oleg is aware of fw190 fuel consumption bug, and it should be fixxed some day. http://forums.ubi.com/groupee_common/emoticons/icon_rolleyes.gif

Heavy_Weather
10-16-2004, 06:32 AM
actually this is modeled correctly now, in the earlier years of the 109's they could only stay in the air for 2 hours at the most. Some German veterans would even say they had to wait til they seen the enemy coming in sometimes before they took off just so they would have enough fuel for the mission. they also marveled at the fact that the mustang could escort bombers on 8 hour missions there and back.

georgeo76
10-16-2004, 06:33 AM
The problem w/ the 109 was not its rate of consumption, but it's low fuel capacity. Check your figures. (I'm almost certain that the Hurri and Spit's gauge is graduated in gallons, not liters.)

Here (http://www.bf109.com/engine.html) is more information on the 109 engine

Patch_whiner
10-16-2004, 06:54 AM
Thanks for the replys. I am not saying the Bf-109's consumption is wrong, just that it is so high compared to many other aircraft.As far as I know the Spitfire/Hurricane have 60 gallons when 100% fuel is applied. For my test the Spitfire used 35 gallons and the Hurricane 25. So 25*4.5=112L for the Hurricane and 35*4.5=157L for the Spitfire. It seems to me that with 400L/90gallons the Bf-109 should have been able to go quite far. I didn't know that there was a bug in the FW-190's rate of consumption. I have always marvelled that it and the Ki-84/Zeke could perform so well with good economy, and put it down to the advantages of radial engines.

PW

F16_Neo
10-16-2004, 07:47 AM
Fuel consumption in the 109's depends a lot on throttle settings. For example E7B can go 100 km on 100 l with shut radiator and 55% throttle...

p1ngu666
10-16-2004, 02:41 PM
using tons of fuel in combat isnt odd, infact it was very much teh norm
infact we may have too long a range on high powers

PBNA-Boosher
10-16-2004, 04:09 PM
If you kept an I-16 at full power for your entire flight, forget overheating problems, it should only have 1/2 an hour of fuel.

WUAF_Badsight
10-16-2004, 04:23 PM
lol not in FB

Tully__
10-16-2004, 05:09 PM
I just test flew the 109-E4 for the following results (altitude less than 1800m):

<pre class="ip-ubbcode-code-pre">
Throttle setting | Duration | Range | Speed
-------------------------------------------------
98% | 52 Mins | ~360km | ~430km/h
32% | 104 Mins | ~460km | ~270km/h
</pre>

Willey
10-16-2004, 05:13 PM
Really funny, the 109Fs have 280l with 50% or something like that. Some 150l more than it should have, and it burs it up quicker than a 109G. That also a way to virtually increase the plane's weight to lower it's flight performance... With 100% you'll fly 40mins maybe. 190A-5-9 30mins.

Korolov
10-16-2004, 05:47 PM
A lot of planes have a specific cruise speed to get the most out of their range. Running at a speed (and power setting) higher or lower than this, and you won't get as effecient fuel consumption.

I don't know what the Bf-109E's cruise speed would be, but I'm sure someone here does.

Tully__
10-16-2004, 05:51 PM
IIRC best cruise is usually fairly close to best climb speed (but a much lower power setting http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif)

Kurfurst__
10-17-2004, 03:49 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Tully__:
I just test flew the 109-E4 for the following results (altitude less than 1800m):

<pre class="ip-ubbcode-code-pre">
Throttle setting | Duration | Range | Speed
-------------------------------------------------
98% | 52 Mins | ~360km | ~430km/h
32% | 104 Mins | ~460km | ~270km/h
</pre> <HR></BLOCKQUOTE>


That would be about correct, IF the obtained range was in miles, not kilometers.

Now where`s that paper...?

Ahah, there it is!

http://www.onpoi.net/ah/pics/users/715_1098006507_bf109e-perf-chart2.jpg

Patch_whiner
10-17-2004, 11:06 AM
Kurfurst, averaging out your figures I get 465km range at max power and 650km range at max economy. In this simulation I can't beleive you could get 465km at full throttle, the only test I did at full throttle was with a 300L drop tank in E-7/B and all 500L was used (50% fuel) and that was for about 300km. Consumption might be a bit higher with a drop tank, but it still seems too far to go (465km) on 400L. So either the simulation is wrong or your table is wrong, I'm not sure which.

PW

p1ngu666
10-17-2004, 11:31 AM
interestin http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

on optium speed, its true, mossies escorted by p51's, both pilots complained. mossie cruise is faster (for max air miles/consumption), so they kept whinning on radio to each other to speed up or slow down http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif

i think there are others that are dodgy, also yak's can overheat at 10000m, but 20%mix, and rad open, and a manifold pressure u can only get down low, at LOW airspeed http://forums.ubi.com/images/smilies/16x16_smiley-very-happy.gif http://forums.ubi.com/images/smilies/16x16_smiley-indifferent.gif

Patch_whiner
10-17-2004, 12:30 PM
For the tests at the start of this thread I should have said they were over 380km not 300km. I get the same as Tully 360km in an Emil at 100% and run out of fuel. The exta 100km is a mystery. What's a mossie by the way ?

p1ngu666
10-17-2004, 03:35 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Patch_whiner:
For the tests at the start of this thread I should have said they were over 380km not 300km. I get the same as Tully 360km in an Emil at 100% and run out of fuel. The exta 100km is a mystery. What's a mossie by the way ? <HR></BLOCKQUOTE>

OMG u poor uninformed heathen http://forums.ubi.com/images/smilies/16x16_smiley-surprised.gif

mossie was a british aircraft, made of balsa and plywood, a unarmed bomber(and photo recon, weather reporting, vip transport,fighter and night fighter) . and its fair say it pwned the germans in teh face. http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif repeatidly http://forums.ubi.com/images/smilies/59.gif

www.mossie.org (http://www.mossie.org) http://forums.ubi.com/images/smilies/16x16_smiley-happy.gif

WTE_Galway
10-17-2004, 05:12 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><font size="-1">quote:</font><HR>Originally posted by Tully__:
IIRC best cruise is usually fairly close to best climb speed (but a much lower power setting http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif) <HR></BLOCKQUOTE>


Its actually a bit more complicated than that. Best endurance (time in air) may be a different speed to best range. Endurance is best at Sea Level whilst range is best at L/Dmax angle of attack and the lowest altitude for full throttle operation

In addition in a war situation engine parts are in short supply and maintenance is performed on a schedule based on hours flown. Therefore, to minimise maintenance, it may be better, to fly faster than the ideal range speed.