I'm trying to come up with some ballpark ranges for RC electric powered aircraft. The literature I find so far on range, like the Breguet range equation, seems focused on mass change from fuel consumption which is not the case in battery powered electric aircraft. So I thought I would start from scratch for my edification and invite sanity checks. McKay's reference, here, provided guidance. Below I've substituted terms convenient for my design. Fundamentally, the maximum range is some optimal aircraft velocity x time aloft, and time aloft is the total energy carried divided by the rate at which it is used, i.e. power, corrected for the efficiency of the propulsion system: R = Vopt x (Ebatt/P) x ε where: R = maximum range Ebatt = energy capacity of the battery ε = propulsion efficiency P = power and since force is power / velocity: R = (Ebatt/Fthrust) ε for level flight: Fthrust = Drag Lift = mg or Fthrust = mg (D/L) where: m = aircraft mass g = gravity L/D = well known lift to drag ratio, or the glide ratio. then R = Ebatt x ε x (L/D) / mg Ebatt = Cbatt x me where: Cbatt = battery specific energy me = mass of battery let fbatt = fraction of aircraft mass dedicated to the battery and me = fbatt m then R = Cbatt x fbatt x m x ε x (L/D) / (mg) finally: R = ( Cbatt/g ) x fbatt x ε x (L/D) The term fbatt x ε x (L/D) is dimensionless. The fundamental range dependent on just carried energy is C/g. Next up, some numbers.