View Full Version : lectric Drive Motors for Taxi Use
atpcliff
2nd Jan 2012, 18:10
EV WORLD: SERENDIPITY - Found Videos and More... (http://evworld.com/serendipity.cfm#1162)
I had heard about this. Didn't realize that control of the aircraft on the ground is much better with this electric drive system than what we currently have. We won't need a tug in the future.
cliff
GRB
Intruder
2nd Jan 2012, 19:37
The developers have been telling us this for 5+ years now, yet there hasn't been a single taker AFAIK...
poldek77
2nd Jan 2012, 21:37
We talked about it a bit:
http://www.pprune.org/tech-log/471453-taxi-electrical-power.html
Wirbelsturm
2nd Jan 2012, 22:16
Makes alot of sense, need bl**dy big motors on a 777 though.
This might make sense if one does a lot of business at smaller facilities without adequate ground handling equipment. I think some military aircraft have such systems for such purposes.
But you'd be paying a weight penalty for the life of the aircraft in increased fuel consumption. If the fuel consumed taxiing was a significant issue, I'd expect to see procedures developed where aircraft are hauled out just short of the runway by a tug. The crew could start engines and take care of some stuff while the tug driver drives them out. But all I've ever seen is tugs used to back the a/c away from the gate or haul them away for maintenance.
grounded27
4th Jan 2012, 16:45
Makes alot of sense, need bl**dy big motors on a 777 though.
Not in all cases, like you understand the bloody big motors are probably bloody heavy. There has to be a point where the fuel burn savings on taxi is ate up over the length of a flight.
Dan Winterland
5th Jan 2012, 02:47
Which will probably be about an hour into the cruise on a 777.
Also, you have to factor in some engines have a minimum warm up time. My current type, it's five minutes. Not only are the engines going to have to be started while motoring/being towed, there's a big risk of missing a slot should either the crew get the timing wrong or an earlier slot become available. This will inevitably lead to some delays. Plus also consider the hassle of a potential start fault away from the ramp.
Monarch used to have a DC10. To save costs, they used to start the number two just before line up. A great idea, except that they were then getting airborne without it having warmed up sufficiently and they had a couple of in flight shutdowns that engine. A number two engine change on that type is a huge problem. It cost them far more in the long run.