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Proportion of MTOW used as fuel on mil jets?

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Proportion of MTOW used as fuel on mil jets?

Old 14th Jun 2015, 15:52
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Proportion of MTOW used as fuel on mil jets?

Staring out of the window on a very long-haul flight yesterday, I got wondering what proportion of MTOW is fuel on most military jets. Typically civilian transport jets have about 30% of MTOW - so I wondered whether this would also be a ball-park figure for military fast jets?
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Old 14th Jun 2015, 15:56
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Proportion of MTOW used as fuel on mil jets?

Sounds about right. Tornado was anywhere from about 25-35% depending upon fit IIRC.
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Old 14th Jun 2015, 15:57
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Tornado F3 - On max internal fuel, about 25%. With max external also, 36%; with AAR........
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Old 14th Jun 2015, 16:14
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C-17 is up at 42%, although that's increased from 31% originally.... Thirsty bird!
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Old 14th Jun 2015, 17:09
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E-3D around 43% (although some is unusable). I think Sentinel is around 45%.

I forget the exact fuel figures for a C-130K (64K? Over ten years since I flew 'em...) round about 40%. J must be a bit less though. A-400 around 36% (from Wikipedia).

All for max fuel/MTOW.
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Old 14th Jun 2015, 18:07
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Vulcan on main tanks around 41% and with double drum tanks 46%.

Full internal plus 21k bombs would be 37%.
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Old 14th Jun 2015, 18:12
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IIRC the figures for the FG1 in Delta(?) fit would work out at about 40%, if I'm wrong I'm sure Courtney can put me right....
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Old 14th Jun 2015, 18:31
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RAF TriStar tankers: over 50% / over 275,000lb.

OAP
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Old 14th Jun 2015, 18:40
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WW,

The C-130K was 62.9k (some figures you never forget) vs MTOW 155k, or just over 40%.

It must be well over 10 years since you last flew them, as they went "metric" in about 1999. Quite what 62,900lbs is in kg I don't recall, it was obviously not a memorable figure!!
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Old 14th Jun 2015, 19:17
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Biggus,

28531 Kgs is the number you might seek in the modern world. Like you, 62,900 lbs is the number that comes to mind. I well remember another version of full tanks. On asking the required fuel load prior to an ASI/MPA flight, the navigator asked me to "fill it till it leaks". Happy days

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Old 14th Jun 2015, 20:10
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Smudge,

I used to operate the Herc tanker out of ASI for the airbridge, only it was to Stanley in my day, not MPA. Four extra fuel tanks plumbed in and mounted in the cargo bay of the tanker, I believe they were old long range Andover tanks, but am happy to be corrected. Total fuel load I think was 62,900 in normal tanks and 28,000 down the back....

As you say, happy days in concertina city, the exiles club, a bungalow in Georgetown, and, towards the end, travellers rest or whatever it was they called the purpose built accommodation....
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Old 14th Jun 2015, 23:21
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Proportion of MTOW used as fuel on mil jets?

Victor K2 52 per cent at heaviest permissible.
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Old 14th Jun 2015, 23:36
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From a standpoint of complete ignorance, would not the ideal answer be: "As much as you can get off the ground with ?"

Says the Ancient Aviator: "Fuel in the bowser is expensive. Fuel in the air is priceless !"

Standing by for incoming......

D.
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Old 15th Jun 2015, 01:40
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There's no point in flying around with more weight than you need. It slows you down, puts extra strain on engines, airframe etc. You also take the landing weight into consideration as well - you can't land if you're too heavy.

So - there's an optimal fuel load rather than just filling it up.
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Old 15th Jun 2015, 03:07
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Proportion of MTOW used as fuel on mil jets?

F18 (not Super) 20-30%.
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Old 15th Jun 2015, 12:30
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Nuther, think you are correct. I always marvelled that Delta fuel at 21k was the same as a Domine MTW. Given an F4 at 54k . . .
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Old 15th Jun 2015, 17:31
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I would guess the F-35 will probably be less due to humping that great big lift fan about that is only actually used on the final part of it's sortie. I think a lot of pilots would probably prefer more fuel or ordnance than dead weight.
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Old 15th Jun 2015, 21:10
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Interesting but not unexpected that the heavy multi-engines took high proportion of fuel in MTOW. Anybody got ball park figures for Lightning and Harrier?
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Old 15th Jun 2015, 21:41
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Biggus

The C-130K was 62.9k (some figures you never forget) vs MTOW 155k
Thanks, wasn't far off then. I was using 160K MTOW for a Mk3 in the fag packet calcs.

I well remember metrication (I was posted away in '04). Bloody farce. Stick-on metric calibrations until the digital conversion.
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Old 17th Jun 2015, 09:50
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Can't find my "newer type" books, but a Hunter T8M was 10%-13%
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