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kenslast Tuesday at 8:10 PM2 repliesview on HN

The claim in the article, "Concorde burned 52% of its fuel just taxiing down the runway", is completely wrong and kind of ruins my confidence in the article. A Concorde used less than 1% of its fuel taxiing down the runway, not 52%.

Source: Air France Flight 4590 Accident Report states that the plane had 95 t of fuel on board when the aircraft started out and used 800 kilos of fuel during taxiing (page 17) and 200 kilos after taxiing before takeoff (page 159). https://www.faa.gov/sites/faa.gov/files/2022-11/Concorde_Acc...

(Since there's a bunch of discussion about how to reduce taxiing consumption, I'll point out that one tonne of aviation fuel is about $700, so there's not much money to be saved by creating battery-powered tugs or whatnot.)

As far as takeoff, "at the start of cruise 20% of the total fuel burnoff will have been consumed while only 9% of the total distance will have been covered." From "Operation Experience on Concorde", a paper by the Design Director. While 20% is a lot, it is much less than 52%. https://www.icas.org/icas_archive/ICAS1976/Page%20563.pdf


Replies

consplast Wednesday at 12:05 AM

9% of the distance but 100% of the altitude. That statement completely ignores the hardest part of the flight (with respect to building potential energy) of getting at altitude.

labcomputerlast Wednesday at 5:26 PM

> (Since there's a bunch of discussion about how to reduce taxiing consumption, I'll point out that one tonne of aviation fuel is about $700, so there's not much money to be saved by creating battery-powered tugs or whatnot.)

Probably the biggest win in aviation emissions would be converting all the ground support vehicles to electric. They’re currently classified as off-road vehicles, so don’t have to adhere to the same emission standards and normal cars and trucks. Additionally, they already spend a lot of time parked at the gate, which makes charging convenient and means that workers are never “waiting” for the vehicle to charge.