Lemme see now ….Re "or fly 200 miles (London to Paris) on a single charge." …...
200 miles @ 300 mph = ETI 40 mins....on a single charge = ENDCE of 40 mins..??
Less 'Reserve' 30 mins = 'Legal' Endce of 10 mins at 300 mph less taxying, acceleration to speed time etc (Such as pointing in the right direction) = Effective 'Legal' Range of maybe something a wee bit short of say, 30 miles......
On a Good Day...….??
Yeah, I know, the longest journey starts with the first step...…..Hoo said that..??.
Good Luck, Cheeerrrsss…...