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Airlines do want to save fuel but the reality is that there are some easy wins that have not been tackled. Before take-off the taxi journey to the runway is und

Airlines do want to save fuel but the reality is that there are some easy wins that have not been tackled. Before take-off the taxi journey to the runway is under jet power when you could have a more efficient tow truck to take the plane there. Concorde was the worst, B52s excepted, 2 tonnes of fuel just to get from the departure lounge to the runway. Then there is the final approach. The Space Shuttle was somewhat brick shaped but they could glide that down from space to land on a runway. Obviously the safety of fare paying planet trashers coming back from their cheap flight is paramount and the peace of those living under the flight path matters not, however, planes could land space shuttle style, gliding in with no fuel being burnt. After 3000 miles of journey this ten miles of coasting might be rounding error, but what if you could catch the jet stream and, rather than take an hour off the journey time, coast as much as possible? If the external costs of cheap flights had to be paid for then I am sure these options would become as standard as 'stop start' is with today's automobiles. Regarding batteries destined to explode, there are ceramic batteries that do not spontaneously combust, imagine if parts of your car/plane/bicycle used such materials, e.g. if the boot liner or bumpers were made of such a lower density battery but doubled up with functionality? It can't be ruled out as possible.

zaarn 8y ago
I checked the ceramic batteries but all I found was replacing electrolyte with ceramic materials. This won't solve all the problems, only some that occur due to physical damage. Since the wikipedia energy density is to my knowledge based on raw chemical performance, there would be no change as ceramics would only allow you to pack existing battery packs more densely. And we're still talking about 2700 tons of battery to carry with the plane. Even if you improved the performance of a battery by an order of magnitude overnight, you'd still perform significantly worse than petrol fuel. Regarding the taxi fuel; that includes other fuel consumption like the APU burning until engine start and 2 tonnes would be the standard usage for larger airports, smaller ones have 1 ton. Also consider that I calculated pure flight performance, if you'd use electric engines to taxi then you'd need an even bigger battery that you can't shed. Taxing by a tow truck is possible but likely too slow (you have to pull an entire airplane). Regarding landing; Spaceshuttles are hardly comparable to normal airplanes. The Spaceshuttle when landing goes a lot faster than most airplanes can safely do at that altitude and requires all brakes and a parachute to slow down on an extra long runway. Airplanes already minimize fuel consumption when there is no engine really needed but for landing a normal airplane you need the engines 999 out of 1000 times.

zaarn 8y ago

I checked the ceramic batteries but all I found was replacing electrolyte with ceramic materials. This won't solve all the problems, only some that occur due to physical damage. Since the wikipedia energy density is to my knowledge based on raw chemical performance, there would be no change as ceramics would only allow you to pack existing battery packs more densely. And we're still talking about 2700 tons of battery to carry with the plane. Even if you improved the performance of a battery by an order of magnitude overnight, you'd still perform significantly worse than petrol fuel. Regarding the taxi fuel; that includes other fuel consumption like the APU burning until engine start and 2 tonnes would be the standard usage for larger airports, smaller ones have 1 ton. Also consider that I calculated pure flight performance, if you'd use electric engines to taxi then you'd need an even bigger battery that you can't shed. Taxing by a tow truck is possible but likely too slow (you have to pull an entire airplane). Regarding landing; Spaceshuttles are hardly comparable to normal airplanes. The Spaceshuttle when landing goes a lot faster than most airplanes can safely do at that altitude and requires all brakes and a parachute to slow down on an extra long runway. Airplanes already minimize fuel consumption when there is no engine really needed but for landing a normal airplane you need the engines 999 out of 1000 times.