空飛ぶクルマの航続性能

抄録

“Flying Car'' or “Air Taxi'' draws attention as next innovation. A lot of Flying Car concepts are proposed and their target range vary from tens to hundreds of kilometers. So, the question is how long Flying Car mission range will be, where battery has only one hundredth energy density comparing to fuel. In this paper the same formulas that can apply to both Flying Car utilizing battery and helicopter utilizing fuel are presented. These formulas are so simple but substantial that range is calculated by multiplying energy density, vehicle L/D and fuel/battery weight ratio. The key to achieve higher Flying Car L/D is how to cope with profile loss of rotary wing employed for vertical flight in cruise condition such as Uber's “Stowed Propeller''. If Uber's vehicle performance targets of L/D 16 and empty weight ratio 0.45 were achieved, the range will be 200km with today's 100Wh/kg battery and can be longer enough to compete against helicopter with next generation battery.