Fuel fraction - the worst offender ?
CG (Gonna get the book)
Join Date: Feb 2017
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On the original subject of fuel fraction: It would be interesting to take a look at the numbers, but if I had to guess I would say that most supersonic fighters have a clean fuel fraction not far off 0.3, and that this number hasn't budged much since the F-4.
The exceptions I can think of are the F-35A/C, the Su-35 (blended), the F-16XL, and the Mudhen with its CFTs.
The exceptions I can think of are the F-35A/C, the Su-35 (blended), the F-16XL, and the Mudhen with its CFTs.
I recall a western enthusiast observing Vietnamese MiG-21's fairly recently reporting about 20-25 minute sorties. Granted no idea what the mission was or the fuel state, but the 21 did/does seem to have a low fuel fraction.
Vietnamese MiG-21's fairly recently reporting about 20-25 minute sorties.
They have a monthly fuel allocation so in the last week there is not a lot of flying.
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As for the MiG-21s - that sounds like the jet we know and love, where a significant fraction of the not-very-large fuel load is of limited use because using it takes you out of CG range. And I doubt that many true-supersonic fighters of that generation would stay up for very long on a runway-launch GCI, using burner all the way from brake release to interception.
Yes, I remember during the Cold War watching Eastern Bloc MiG-21s departing on regular training sorties, returning after just 20-30 minutes, no external fuel tanks fitted, just wing mounted rocket pods.
Salute!
I don't know about all the concepts of short range and limited fuel except for Britain and some of the old Soviet places. Yep, Vietnam was like that up north.
Maybe the Cannucks will jump in here, but we "interceptors' flew about 200+ n.m. from northern USAF bases and the Canadians were 200 miles north of us! So our NORAD plan was to hit the Bisons and Bears way up north and attrite them. None of this 10 minutes to engagement mentality.
My Voodoo unit at Grand Forks used one 300 gal external or even "clean" configuration. Burner for takeoff unless it was really cold, then cruise at 35K and bout 5,000 or 6,000 pounds per hour at 500 knots TAS.
The new guys like the F-35 and Raptor and even the F-16 are better.
BTW, my flight commander for F-102 training was a Brit Lightning guy. And even than, he liked the extra gas we had in the Deuce.
Gums sends...
I don't know about all the concepts of short range and limited fuel except for Britain and some of the old Soviet places. Yep, Vietnam was like that up north.
Maybe the Cannucks will jump in here, but we "interceptors' flew about 200+ n.m. from northern USAF bases and the Canadians were 200 miles north of us! So our NORAD plan was to hit the Bisons and Bears way up north and attrite them. None of this 10 minutes to engagement mentality.
My Voodoo unit at Grand Forks used one 300 gal external or even "clean" configuration. Burner for takeoff unless it was really cold, then cruise at 35K and bout 5,000 or 6,000 pounds per hour at 500 knots TAS.
The new guys like the F-35 and Raptor and even the F-16 are better.
BTW, my flight commander for F-102 training was a Brit Lightning guy. And even than, he liked the extra gas we had in the Deuce.
Gums sends...
