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Old September 13th 18, 02:52 AM posted to rec.aviation.soaring
Emir Sherbi
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Posts: 64
Default Js3 jet catastrophic failure.

I'm not prepared to go the electric method just yet as the current high energy density battery cells are dangerous when shorted, damaged in any way, run down, or indeed suffering from hidden manufacturing defects. It has been 10 years since the Tesla Roadster came out and current batteries have higher energy density but the other defects are still there. Any battery technology announced now is likely 5 to 10 years from being able to be bought commercially. I'm willing to be proved wrong on this but electric gliders need both high energy density and high power density and reasonable cycle life(at least 200 cycles depending on cost)along with resistance to catastrophic failure that results in fire.

Mike



Mike,

Today only safety is a "concern". Because we are very used to accept that if something with fuel exploded is a normal thing and if a battery catches fire its a big news story. Of course there is a long road ahead to make everything fail and fool proof.

Most of the times you will not land out at more than 100km from your home base.
For the same weight of an internal combustion sustainer system you get the self launch capabilities and a very long retrieve with electric (maybe more than 100 depending in a lot of variables).
For the life cycles, only if you land out in every flight you will get 200 cycles with very safe and proven cells. If you only self launch you can get 400 cycles or more.
Power density is not a problem for this application, neither the energy density. Of course that would be perfect if the batteries weight only 10kg, but with today's 30kg that is not much an issue.


Emir