An autopilot is just a computer, and theoretically could be programmed for auto takeoff, but there aren't any which do so now.
If you were to set the auto pilot and auto throttle at the end of the runway the aircraft would attempt to rotate to takeoff pitch immediately. That would delay liftoff significantly and almost certainly result in a tail strike due to the deck angle. Once airborne there would have to be some intervention to change from TO/GA mode to NAV+ALT for level flight. Then there is the problem of reconfiguring, as gear and flaps are not auto controlled, and can't be left down - unless you want to fly around at 200kts all day.
This doesn't even address the problem of getting to and lining up on the runway without guidance.
It could be done, but nobody has bothered as there's no real need. There are two expensive problems...
1. An autopilot needs guidance...it can use the same ILS that a human uses for approach and LDG but no such thing exists for TO. Current localizer systems could probably be modified to do that but at great expense...the antenna would need to be moved from the far end of the runway downrange at least several miles to allow for an alternate nav mode before station passage. GPS might also be a possibility there.
2. Engine failure. You might be able to re-program existing autopilots to deal with that except for one thing: The rudder. Most (or all?) airliners do not have an autopilot for the rudder. They have a yaw damper but that's not designed to apply the large rudder deflections needed for a V1 cut. This would require significant redesign...more $$$
Nobody is going to spend money to create a solution in search of a problem.
I think the F14 had a mode for auto cat shots, the F18 may also.
If a plane can roll out at the end of a CAT III, it could do a takeoff roll. It would take some programing to rotate at Vr but could be do able. But as ahs been said, it's an answer looking for a problem.
I think the F14 had a mode for auto cat shots, the F18 may also.
If a plane can roll out at the end of a CAT III, it could do a takeoff roll. It would take some programing to rotate at Vr but could be do able. But as ahs been said, it's an answer looking for a problem.
There is nothing automatic about the cat shot
Just pure physics!
You might be thinking that because you see the pilot put his hand up on the right grip just before launch. The flight controls are already set for the proper AOA on takeoff.
2. Engine failure. You might be able to re-program existing autopilots to deal with that except for one thing: The rudder. Most (or all?) airliners do not have an autopilot for the rudder. They have a yaw damper but that's not designed to apply the large rudder deflections needed for a V1 cut. This would require significant redesign...more $$$
The 75, 76 and 777 have rudder inputs during CAT III approaches. Also, the 777 has a thrust asymmetry computer that puts in some of the needed rudder during an engine failure. The 737-300/500 is the only CAT III airplane I've flown that did not have rudder inputs from the auto pilot.
People like to claim that the Lockheed L1011 was capable of automatic take-offs; if you google "L1011 auto take-off" you'll get quite a few hits but I couldn't find a really good reference.
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