4 ms·
A320 family range varies from 5500km to 8700km, so "a fifth of it's range" is around 1500km, which is 80% of the industry emissions. I'm not sure of that quote
by isostatic 7y ago
A320 family range varies from 5500km to 8700km, so "a fifth of it's range" is around 1500km, which is 80% of the industry emissions.
I'm not sure of that quote either -- a lithium ion battery is currently about 1MJ/kg and 1MJ/litre. Jet fuel is 43MJ/kg and 35MJ per litre (values from from wikipedia)
So a battery that's 30 times more energy dense will be in the region of jet fuel, and thus would presumably be able to fly an A320 for its current range with its current payload.
To do current payloads at 1/4 range (what you'd need for those flights under 1500km) at A320 payloads, you'd need batteries to presumably be in the 5-10 times as dense level, and that's the range that lithium-air batteries would sit.
- gambiting 7y agoDon't forget that the fact that the fuel is burnt up as you travel is a big factor in the range of an aircraft. The weight of batteries does not go down during the flight.
- murkt 7y agoHow much does this affect an aircraft range? I assume the mechanism is that lighter aircraft needs less lift, and less lift means less drag, less drag - less power on the engines - less fuel consumption - more range. I somehow always thought that more weight of an aircraft lessened its range almost only because it needs much more power to take off and gain a cruising altitude.
- hervature 7y agoIt adds a logarithmic factor: https://aviation.stackexchange.com/questions/45439/how-much-of-an-improvement-would-a-1-weight-decrease-on-an-airplane-be-to-the-i https://aviation.stackexchange.com/questions/45439/how-much-...
- Someone 7y agoEven ignoring more efficient flight at lower weight, https://en.wikipedia.org/wiki/List_of_airliners_by_maximum_takeoff_weight https://en.wikipedia.org/wiki/List_of_airliners_by_maximum_t... shows that maximum landing weight can be a lot lower than maximum take-off weight. So, to land at take-off weight, you’ll have to significantly strengthen the landing gear. That already is 2.5 to 5% of the Maximum takeoff weight and 20% of the airframe direct maintenance cost (https://en.wikipedia.org/wiki/Landing_gear#Aircraft_landing_gear https://en.wikipedia.org/wiki/Landing_gear#Aircraft_landing_...)
- usrusr 7y agoThe 80% figure are flights longer than 1500 km. 1500 and less are the 20%. So even if all those flights were switched to magic zero emission electricity, the aggregate improvement over the whole industry would barely beat the relative improvement between a 737 NG and a MAX. (yes, this is an apples to orchards comparison)
- isostatic 7y agoSo they do, that'll teach me for not reading twice
- rbanffy 7y agoTo be fair, the MAX has been zero emission for a couple months now.
- isostatic 7y agonot getting many mpg though
- rootusrootus 7y agoThat's not strictly correct. There are MAX's flying every day. At this moment, there are two in the sky. Grounded from carrying passengers, but not grounded entirely from flying, and certainly emitting in any case. The two on the map now are out of Boeing Field.
- Gibbon1 7y ago> Jet fuel is 43MJ/kg and 35MJ per litre (values from from wikipedia) Jet fuel is really about 12-15 MJ/kg when you take thermodynamic losses into account. So you;d need a battery 10 times as dense. Which likely isn't happening any time soon, but still. I think with full electric aircraft it's not a case of 'won't work' but how big of a niche they can carve out. Probably the sector they'd compete in are general aviation and puddle jumpers.