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aviatorchris
  - Joined on 02-23-2009
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I hope I don't bore people to death with this,but in my opinion, definitely the ninth wonder of the world! I asked questions of Rolls Royce given that the Conways were the biggest criticism of the plane.
The dialogue went like this...... Good aternoon. I am a civil aviation enthusiast and my favourite craft of all
time was the Vickers VC10, powered by RR Conways all those years ago, (although still
with the RAF currently).
Two questions.
1) If someone was bright enough to actually update the Super VC10 as a rear engined wide
bodied jet, would it be a successful project using either a) two Trents of
designated size or four V2500 upgrated, and could they be carried sucessfully at
the rear of the fuselage?.
2) Could existing VC10's be upgraded using 4 x V2500 22000 lb thrust, and if so
how much more energy efficient and quiet would they be compared with the old
Conway, which without doubt was itself a superb power unit at that time.
Hope you will reply, best wishes, Chris Byrne Chris Byrne,Your email re the VC10 to the Heritage Trust has been passed to me for a reply. To be blunt and give a simple answer, the answer to both of your questions is NO. To be sure I am not being unkind to the VC10, I have checked with one of my old colleagues who spent a lifetime in the design of civil airliners to confirm that my views are fair and reasonable. You have only got to look at all the succesful civil aircraft today, Boeing 737, 747, 757, 767, 777, 787, Airbus A300, 310 320, 330, 340, 350XWB and the A380, not to mention the Embraer 195 etc, they have all followed the layout of the Boeing 707. In fact it takes a real expert to tell them apart. Although the 727 was rear mounted and succesful, the Trident, the BAC1-11 and the VC 10 were never the success that the 737 or A320 are. The British were obsessed with clean wings and whilst they had their advantages, it never out weighed the disadvantages. Any engineering design is a compromise and experience shows Boeing with the 707 got it right! With the rear mounts you got the problem associated with getting the fuel lines from the wing tanks through the fuselage under the passengers back to the engine. If you check the VC10 all up weight (AUW) versus the 707, I think you will find for a given payload the VC10 is the heavier. For example, the wing structure on the VC10 has to be a lot stronger and heavier than the 707 as the VC10 gets no wing relief from the weight of the engines. The lift is bending the wings up, the fuel and the engines (in the case of the 707) are helping to resist this lift force. When the VC10 has burnt all its fuel off, the wing roots have to be strong enough to resist the lift bending alone, no help from the engine weight. Stronger wings mean heavier wings! Contaiment with rear mounted engine is more of a problem, with the engines being closer to the fuselage. By containment I mean that should you have a Turbine or compressor disc fail and not be contained within the engine you have to be able to demonstrate to the authorities that you do not hazard the aircraft. This is easier on wing mounted engines. The balance of the VC10 is more difficult, the wings have to be further back. Whilst it may allow more rotation for shorter take-offs, the aircraft trim problems are more tricky. Whilst Rolls-Royce we the first with the turbofans with the Conway (bypass ratio 0.5), we were slow to exploit their full potential; it was not helped by Vickers obsession with clean wings and buried engines (eg V1000). Podded engines on the 707 had no such restrictions, The P&W JT3D on 707-320 had bypass ratios of approaching 2.0 and the wide bodies of today are around 6.0 and Boeing 787 and Airbus 350 will be up at about 10.0. These are just a few of the reasons that the 707 was a success and the VC10 was not! I would recommend the paperback book 'The Road to the 707' by William H Cook - availabe from Amazon for £13.94 - it covers in depth but not too technical, the story of the civil aircraft from the Boeing 247 and Douglas DC1 through to the 707 and clearly tells how Boeing got it right! On a personal note, I always preferred the 707 to a VC10 on my 1960s trans-atlantic crossings - a much better ride! and recently confirmed by a sortie in one of the RAF's VC10 on a refuelling flight over the North Sea! Hope you find this of some use. Sorry I cannot be more supportive of your favourite plane! RegardsDave Piggott
Is this a fair assessment? Discuss!!
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