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Old 25th Nov 2005, 13:35
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rhajaramjet
 
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Lightning climb-to-height records

Interesting stories that need a little closer examination. With well over 2000 hrs on the jet, all Marks and in every theatre they ever operated, I do have a bit of "bin there, done that" to contribute.
By the way, somebody may like to check the RAF retired list; I think that Brian Caroll was a sqn ldr when he retired, and civilian instructors in Saudi were always referred to as 'mister', something the RSAF was very strict about.

Now, the RB57F story - the Canberra had a very strict Mcrit of .86M, so it seems reasonable that the RB57's, with that big wing, was somewhat less. But even assuming that it had a very slow stall speed, it's Vmin would have equalled Mcrit at somewhere around 70,000 ft. So to claim that he "climbed from 65,000 to 80,000 ft whilst flying a 180 turn" is extremely dubious; he would have been out of control well before he got up there. And as for his altitude on the last run being "into six figures", well, I suggest you simply read some of the many reports about U2 handling at altitude if you need any more convincing.

Anyway, about the high-speed/zoom-climb reports. The trial reports from AFDS, Pete Ginger and Dennis Witham were all consistent about the critical importance of gentle stick pull (back pressure) climb angle and engine handling - needed much trial and error and practice. In Dennis Witham's words, "with practice, and the right conditions, it was possible to consistently achieve between 72,000 and 75,000 ft." And that was in clean shiny trials aircraft, without any operational kit. Sqn jets, especially later, were dirtier, heavier and, with all the cooling and overboard drain mods, had more drag. After accelerating to M2 the F3 didn't have a lot of fuel to play with, so ORAC's tale of the Wtm jet may have had a Mirage doing less than the claimed M2.1+. The F6 had more fuel but was draggier and so burned more getting to and staying at M2. Even so, I doubt very much that Mike Hale's Concorde was doing M2.2 - just think what the Mach and IAS would have been to overtake it at that height! As I recall, that trial had the Concorde at M1.4, as much for acceleration, turn and slow-down (boom) reasons as the Blinder he was simulating. With you, BOAC!
As for the tales related by jimgriff, I'm curious that neither pilots made any mention of intake vibration, which occurs above M1.88, both seemed to have full reheat, despite being well beyond the reheat burning zones, and both of them would have been well into the moderate buffet boundary at that altitude, despite being at M2. But not mentioned. When I get a moment, I'll take my OR946 height module apart to see what max altitude it could display. Don't be misled by the high trop - it just means it was colder (a little more thrust), the flt controls, buffet, engine handling limits, etc, would be unchanged.
So I remain open-minded about the veracity of those particular climb reports. Perhaps somebody would like to look up the mach number/IAS relationship at 87,000 ft?

Vulcan News - sorry mate, forgot to comment that when we had an F3 to fly without ventral for a few days, biggest problem was getting the nose gear up on take-off before the limiting speed ! Presumably Mike B-H will plan accordingly.
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