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Aircraft fuel efficiency has improved by more than 50% since the 1960s. Most people would call that more than "a few percent".
by Turing_Machine 9y ago
Aircraft fuel efficiency has improved by more than 50% since the 1960s. Most people would call that more than "a few percent".
- chris_va 9y agoTo be fair, the cost of jet fuel has increased by more than 50% too, and won't be the dominant cost if they are only shipping 70 jets.
- Turing_Machine 9y agoBut the comparison is with the costs of the Concorde when it was shut down in 2003, not the costs of the Concorde in the 1960s.
- valuearb 9y agoAccording to US census bureau, per capital income in US has increased by 10x since late 60s. Jet fuel prices have increased around 6x, from around 30 cents to around $2. So wouldn’t that make jet fuel more affordable?
- joezydeco 9y agoDid you account for inflation? $1 in 1970 is worth $6.52 now.
- Godel_unicode 9y agoInflation, the general rate at which the price of goods and services is rising and falling, is literally the calculation made in the post to which you have replied.
- WalterBright 9y agoThat's subsonic fuel efficiency. Supersonic is another thing entirely. The supersonic wing is also terrible at subsonic speeds, meaning it takes a terrifying amount of fuel to push it up to altitude and supersonic. Military supersonics deal with this by getting a drink from a tanker after takeoff.
- neurotech1 9y agoBoom are flying with turbofan engines, not the turbojet engines that were common in the 60s. As for aerodynamics, the F-22 is relatively efficient at high subsonic speed and also doesn't require external tanks like earlier jets do.
- WalterBright 9y agoWikipedia says that the F-22 is able to supercruise without afterburner, using turbofan engines. This may be the key.
- techdragon 9y agoSupersonic capable turbofans that are able to get the "force multiplier" of using bypass airflow for thrust at supersonic speeds are honestly the key enabling technology here.
- ddalex 9y agoSo basically a supersonic turbofan is a SCRAMJET behind the first fan?
- techdragon 9y agoNot being an expert on supersonic turbofans, I went to the obvious first information source and it was surprisingly illustrative. https://en.m.wikipedia.org/wiki/Turbofan https://en.m.wikipedia.org/wiki/Turbofan From a little further reading it seems it seems that supersonic turbofans are actually just the apex of the continued sophisticated work being done on jet engines which has allowed them to push the intake fans of low bypass turbofans up to supersonic airflow speeds.
- gaius 9y agoAs is the Typhoon
- swendoog 9y ago