IIRC, the superiority of Guinness as consumed in the Emerald Isle was always put down to the Liffey water in the days it was also brewed in Blighty. That theory no longer holds water...
Ahem! Judging from all the previous posts, this premature nose-wheel-lifting technique seems to have three possible explanations: tradition, propensity to shimmy, or tyre-speed limitations. The
parallel thread on AH&N has a posting by Dave Reid with a video of a Comet IV, which seems to be extending its nose oleo for quite a long time before rotation. (I doubt the nose-wheels are actually clear of the runway, but stand to be corrected.) Starting from 1971, I don't remember being taught to do this on any jet airliner, although the VC10 and One Eleven had been known to suffer shimmy on occasion. I think neutral elevator was the norm, or even a bit of down elevator in a crosswind. (BTW, the B707-320 would allegedly rotate spontaneously at about V2 without pilot input - it used to be demonstrated in the sim.)
Then there's the matter of tyre-speed limits. On a civil aeroplane it would surely be illegal to plan a take-off with a VR, or even V2, that involved a ground-speed above the nose-tyre speed-limit? And would the same restriction not apply to military ops in peacetime?
I was at Brooklands today, and can confirm that the ex-BUA/BCAL/Omani Type 1103 VC10 has 225 mph chined tyres fitted to its nose-wheels, as I remember from flying it in the early 1970s. FWIW, the Type 1101 fuselage also on display (G-ARVM), on the other hand, has a pair of very aged 200 mph chined tyres. In still-air at Nairobi, that could have been the most limiting factor for the RTOW calculation, although I don't have any performance graphs for the Type 1101.
Originally Posted by
Tengah Type
[...]
The RAF had the VC10CMk1, which was the new aircraft for 10 Sqn. These were a Hybrid with Standard (ie short) body and Super wings. These had the ODMs for the type. When we acquired the Tanker aircraft we had old BOAC/Gulf Air Standards as K2s and Old East African Airways Supers as K3s. All the aircraft had the same standardised engines.
The Tanker ODMs were produced to different standards to the original RAF VC10 C1s, and did not cover the same operating limits (more limiting) as it was not envisaged that we would operate worldwide, thereby saving a couple of quid in their production.
The ODM was produced for the K2(Standard) with fiddle factors to be applied to the K3. The K4(Ex BA Supers) had the same performance as the K3s.
We had Regulated TakeOff Graphs(RTOGs) produced, for the various types,
at selected airfields as well as Balanced Field Graphs you could use if Max TOW was not a problem.
If you had to operate at MTOW from an airfield that was not in the book of RTOGS it was back to struggling with the ODM.
Thanks, TT. Your operation was a lot more complex than ours... (What is "ODM"?) I wonder if
Jhieminga is following this VC10 nostalgia... The CMk1 seems to have been a development of the Type 1103: standard fuselage, "combi" with "super" wing; the improvements being "super" engines and an APU? Did it also have the fin fuel-tank of the Supers? The ex-EAAC Super VC10s, like the K3 now at Dunsfold (the last VC10 off the Brooklands production line), were also combis and therefore easier to insert the fuselage fuel-tanks.