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Jetdoc
5th Jun 2006, 20:09
I'd like to know why the autopilot is not used or can not be used for the takeoff phase of the flight.

Mad (Flt) Scientist
5th Jun 2006, 20:48
I'd suggest reaction time issues might be a factor - typically when a failure occurs with AP on the time assumed for the crew to recognise the failure and react to it is assumed to be longer than for hands-on flying. If you had to assume, say, a 4 second dwell at V1 instead of 2 seconds, for the rejection case, the distance penalties might be considerable.

hetfield
5th Jun 2006, 20:57
After pushback I engage the autopilot.

On blocks, I switch it off. Sometimes the copilot does it.

411A
5th Jun 2006, 23:18
Ah, well actually, Jetdoc, the autopilot CAN be used during takeoff on a few types, the Lockheed TriStar*, is but one example.

*Except for those that were on the British register, oddly enough.
Never understood just why.
It must be a British thing...:rolleyes:

multi_engined
6th Jun 2006, 00:48
Why would an autopilot even need to be used for takeoff? Pilots seem to do such little hands on flying these days with all the technology avaliable.

They do a great job anyway, much better than what an autopilot could do, why fix something that isn't broken? :eek:

Jetdoc
6th Jun 2006, 04:02
Actually, I heard an explanation about 25 years ago but I can't remember it. FD has a takeoff mode and maybe there may be a CWS takeoff mode but there still seems to be no command takeoff mode.
All I've found so far is some FAA info related to not engaging an autopilot at low altitudes axcept for autoland modes.

Dani
6th Jun 2006, 07:38
I would say it's a certification problem. Technically I see no problem why it shouldn't be possible. Lots of airplane take off automatically (because they don't have a pilot in the cockpit).

The reason why it's not certified is most probably because pilots have to manually abort if something goes wrong. An automatic could also decide but that's (fortunately) not yet the case. So if you would have to switch of the autopilot first and then abort the TO this would cause more delay and maybe more overruns/other incidents/accidents.

Just my thoughts, no regulations to back it up.

Dani

rhovsquared
8th Jun 2006, 21:24
Admittedly, I was very skeptical at first about "auto takeoff" ability on the
L-1011, but after both 411A and in a prior thread FE Hoppy said it possible, I am amazed and convinced, but what about those weird cases? such as when an abort must be done after Vr for extreme situations...yes it happens. what will it do then? I think ALL takeoffs should be done with the pilot's hands and feet:= ...just in case:ouch: