Armchair Decisions
Quote from Diesel 8:
So Chris, in the VC10, if you are at VR and both donkeys on one side decides it is time to eat hay, are you stopping?
[Unquote]
The short (and honest) answer is that I don’t know. The slippery one is that you haven’t supplied me with enough data! [You should ask one of the RAF guys; I’m over 30 years out of date.] Think I should admit first that anything offered here is, by definition, merely an armchair decision...
Let’s assume that ssg’s 5000ft-excess of Balanced Field is leaving us with about 5500ft of runway remaining at Vr.
At sea-level, if not already rotated, I think I’d go, as she should fly okay − even at MTOW. But with that amount of pavement remaining, she should also be able to stop. If rotated significantly, I’d go.
At Nairobi (5327ft amsl, if memory serves), both options are less attractive. TAS/GS would be higher; thrust lower. We’ve already used 8000ft of the 13500ft runway, so we are pretty heavy. Initial climb would be marginal. The gear will have to stay down initially, because of the extra drag of opening the gear doors. Think I’d stop, and almost certainly overrun the runway. If already rotated, I’d have to go, and fuel dumping would start asap.
On the B707-320 with 2 out on the same side, the decision is simple: stop in all cases; because of lack of thrust when heavy, and the high Vmca[2] when light. Cannot comment on the various types of DC-8s, B747s and A340s; never flew them.
Last edited by Chris Scott; 22nd May 2008 at 09:40.
Reason: In the comfort and safety of my home.