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Metatron_123
02-26-2008, 05:30 AM
I'm curious as to what the range of, say, a Bf-109 K-4 is with a drop tank attached.

It's normal range is about 560 km.

I want to see how much the 109 could increase it's range.

Also if anyone can tell me the range performance of the experimental 109 with two tanks attached, I'd appreciate it.

Metatron_123
02-26-2008, 05:30 AM
I'm curious as to what the range of, say, a Bf-109 K-4 is with a drop tank attached.

It's normal range is about 560 km.

I want to see how much the 109 could increase it's range.

Also if anyone can tell me the range performance of the experimental 109 with two tanks attached, I'd appreciate it.

OMK_Hand
02-26-2008, 11:26 AM
Hi Metatron_123.

Good question.
According to Jane's fighting aircraft of WWII, the Me109 K4 has a range of 584 km.
Presumably this takes; take off, climb, cruise, combat, and landing etc. into account?.

The internal fuel load is stated as being 88 Imperial gallons for the 109 G
(The 'K' series is stated as being a development of the 'G', with a different engine and 'minor structual differences. Same fuel tank as 'G' despite increased range?)

The general external drop tank is credited as holding 66 Imperial gallons.

So, (correct me if I'm wrong http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif)

584 (range km)/88 (internal fuel) = 6.636 km per gallon.
66 (external fuel) x 6.636 (km per gallon) = 437.976 (range)
437.976 + 584 = 1021.976 km total range.

Therefore: 1021 km range.

There was a thread recently about range/fuel in the game, and how accurate it all is. It's worth experimenting to see. 1000 km is a loooong flight to try though...

Also, I don't know how accurate Jane's is, it was produced just after the war so might be a bit off since everything was 'sensitive' still...

Hope this helps http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Kurfurst__
02-26-2008, 11:36 AM
The figure you have given appears to maximum cruise conditions without a droptank, ie. datasheet shows this as 585 km achieved at a cruise speed of 645 km/h (400 mph).

German range tables give the following speeds for the different 109 variants at maximum range conditions, with a single droptank.

Maximum range of Bf 109E-7 with droptank was 1350 km, endurance 3h 50 min.

Maximum range of Bf 109F-4 with droptank was 1660 km, endurance 5h 15 min.

Maximum range of Bf 109G-2/G-6 with droptank was 1700 to 2000 km, endurance 5h 20 min to 6 hours.
Without droptank, it is given as 990 to 1160 km, endurance 3h 5min to 3h 25 min.
(Different documents give different values, probably under different conditions specificed)

From this, for the two droptank version (LR recce variants used this configuration), roughly 2600-2900 km range seems a reasonable figure.

I know of no maximum range table for the 109K, only under maximum cruise conditions (585 km); . Some conlclusions can be drawn from these datas, as the K-4 is listed as with ca 6% greater range than the 109G under maximum cruise conditions, probably down to increased aerodynamic cleanness and/or more efficient powerplant (higher CR motor).

In addition, the 109K had the ability to carry 118 liter (+29,5%) more fuel internally in its rear aux. tank - in this case MW50 was not carried (it used the same tank).

I`d say the 109K-4s maximum range was 1850 - 2100 km, and could be extended to something like 2100-2400 km if the rear tank was used an aux. LR fuel tank (and no MW 50 carried. However with C-3 grade fuel the performance would be similiar as with the lower grade fuel, MW-50).

OMK_Hand
02-26-2008, 11:43 AM
Well, it got the ball rolling http://forums.ubi.com/images/smilies/16x16_smiley-wink.gif

Presumably, the ranges in Janes are approximate 'effective combat' ranges?

Metatron_123
02-26-2008, 11:53 AM
Well Kurfurst, if your figures are right then it's much more than I presumed it would be!

From a small Jane's WW2 Fighter hand book I have, the range given for BF-109 G-6 with droptank is around 998 km.

Not that this is the most valid source.

Edit: I also own Jane's Fighting Aircraft, interesting book as it retains it's propaganda qualities. The beginning of the book is full of 'Luftwaffe bashing, RAF praising' style talk.

Very biased, but the performance figures for the aircraft listed in it doesn't seem too wrong...

OMK_Hand
02-26-2008, 12:08 PM
From a Finnish manual in English for Me109 G6.

Volume of fuselage fuel tank ca. 420 L (92.38)
Jettisonable auxiliary tank 285 L (62.69 gal)

Cross country flight:
manifold pressure 1.0
revolutions 2000 - 2100 rev./min

I think this is an economy cruise.
A 'regular' cruise is (I think):
manifold pressure 1.15
revolutions 2300 rev./min

Range at cruising speed ca. 550 km (without tank.)

<span class="ev_code_YELLOW">Radius of operation </span> with auxiliary fuel tank at cruising speed ca. 450 km.

http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

Kurfurst__
02-26-2008, 12:26 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Metatron_123:
From a small Jane's WW2 Fighter hand book I have, the range given for BF-109 G-6 with droptank is around 998 km. </div></BLOCKQUOTE>

Its also correct, but its for a high speed cruise at ~ 600 km/h, ie. not very economic.

Thing is, the more available German datasheets, which Jane`s and other use as the source of their data only list the 109G range figures at this high speed cruise; no other data is given in them, the cell was left empty; this range also coicides with the 109E range (660km w/o droptank) at economic cruise.
For other aircraft, where economic cruise ranges are more available from common datasheets, this economic (and uncomparalbe) range figure is given.

All aircraft reach their maximum ranges at much lower speeds, typically around 350-400 km/h.

In addition, the given figures are greatly impacted how is the range calculated - how much is reserved for warm up, take off, is climb/descent included, is there a 'safety' increased consumption figure used (i.e. the F-4 Reichweitentabelle assumed 15% higher consumption than the nominal).

Usually most range tables do not include high power outputs in the flight profile, ie. combat, when fuel is consumed in huge quantities, and very fast.

BTW, if it`s the old 1946 Jane`s book, it actually just repeats word-by-word some old RAF paper about LW types, boosts, etc. Jane`s basically copy-pasted this. Its not bad though, more reliable than most similiar papers, actually.

thefruitbat
02-26-2008, 12:30 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">BTW, if it`s the old 1946 Jane`s book, it actually just repeats word-by-word some old RAF paper about LW types, boosts, etc. Jane`s basically copy-pasted this. Its not bad though, more reliable than most similiar papers, actually. </div></BLOCKQUOTE>

wow, i can't believe you just posted that, lol.

fruitbat, slightly pulling your leg... Interesting info though, thanks

PhantomKira
02-26-2008, 12:46 PM
The below assumes you're looking for in-game values that the AI gives you, not real-world. I'd assume that different altitude and airspeed combinations would vary things.

I don't know how well the AI handle fuel consumption, or if you want to leave it to them, but one of the things I do to test an aircraft's performance prior to making a mission is I get an open map [Pacific, little to render] and put one aircraft on it, with waypoints a long ways away from each other, then simply use the time compression (Shift + S) to make the time go by much faster.

Please note, the figures below are AI controlled aircraft, so the speeds are slightly off. Also, I don't account for reduced speed and increased fuel consumption in a climb.

So...


Bf-109K-4 Clean, ground start

Alt 7000m
Speed 300km/h

1h 45 min endurance

105min at 300km/h = 1.75h x 300km/h = 525km [approx 500km with other factors]


Bf-109K-4 Drop Tank, ground start

Alt 7000m
Speed 300km/h

2h 55min endurance

175min at 300km/h = 2.91h x 300km/h = 873km
[approx 840km with other factors]

The testing for these two flights took all of maybe 7-10 minutes total, with the math.