alt Hacker News> ”the 767 burns about a tonne taxiing”
This seems incredibly inefficient. Is there a future for hybrid aircraft, which would feature both traditional turbofans and large batteries for energy storage?
Batteries would eliminate the need for an APU and power the aircraft during taxi, allowing the engines to be started just before actual takeoff, and shut down immediately after landing.
Either the batteries could power wheel motors directly during taxi, or the aircraft could mix turbofans with e-fans (which could also allow energy recovery during descent and help power the aircraft during cruise, reducing fuel consumption further).
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Electric taxiing (on APU) has been in development for over a decade, but it's mostly intended for single aisles (the shorter the flight the more the taxi overhead), and the relatively low fuel prices has led to these projects mostly dying off: L3 shuttered their effort in 2013, Honeywell and Safran's EGTS joint venture was dissolved in 2016, and wheeltug... apparently still lives (with no support from either boeing or airbus), though it was initially supposed to enter service in 2018.
> This seems incredibly inefficient. Is there a future for hybrid aircraft, which would feature both traditional turbofans and large batteries for energy storage?
I would assume the extra weight would make it not really worth the added cost and complexity.
Airport tugs might be a better fit to improve ground operations efficiency?
I think they've looked at that kind of thing but not found if practical so far. One innovation has been airbus jets taxiing with just one engine which cuts fuel use a lot as it mostly goes to just spinning the engines.
eTAXI is just one such solution
https://www.safran-group.com/videos/e-taxi-safran-unveils-it...
> This seems incredibly inefficient.
Very inefficient but good for safety: if an engine is failing, you hopefully might discover that while taxiing rather than when you are in the death zone 25 meters up in the air.