4 ms·
At the altitude they used to fly at there wasn't much air resistance. I think it's more the acceleration and climb out phases when they are using the reheat (ak
by willyt 4y ago
At the altitude they used to fly at there wasn't much air resistance. I think it's more the acceleration and climb out phases when they are using the reheat (aka afterburner). Cruising at ~50-60000 feet, Concorde was pretty efficient, comparable fuel burn to a 747 from that era, but the engines were super inefficient in all the other phases of flight. I've heard it said that it used more fuel to taxi to the end of the runway at Heathrow than a modern A320 would use to fly London to Paris. (Someone else can google that to see if it's true! I can't be bothered.)
- Ekaros 4y agoWheel mounted electric engines? Only turn engines on when close to runway the batteries can't weight more than the fuel.
- sofixa 4y agoSafran showed a POC of this a couple of years ago at the Bourget airshow, but i have no idea why it hasn't taken on - their pitch was pretty good.
- LgWoodenBadger 4y agoOr just use a tug, which everyone has everywhere, 99% of the way
- smachiz 4y agoThe taxiing was bad, but that wasn't the worst of it. To go from subsonic to mach 1.7 the Concorde used reheat ("afterburner") that just dumps fuel into the already hot exhaust. This is not particularly efficient. Then from 1.7 to mach 2 it didn't need reheat, and at mach 2 it was quite efficient of an engine design.
- smachiz 4y agoA 747 carries 500 passengers, Concorde carried 100. Your costs per seat mile are going to be at least 5x higher. The Concorde engine was efficient at cruise - and pretty awful everywhere else. At cruise it was about 10% more efficient than a GE90. But the Concorde had 4 of them, and a 777 has 2 GE90s. This is also why you don't see 4 engined planes anymore, except for the A380 and most people were hell bent on retiring during the pandemic until they couldn't get more 787s/A350s and the 777X is delayed.