Helicopter HP/kg

• 10 lb per hp - this specifies 130 HP for 1300 lb weight [1]. 260 lb engine [2] 1300 lb total weight.
• 7 lb/HP - [3]
• 5 lb/HP for heavy cargo of 10 tons [4]. 2000 lb engine weight to 50000 lb gross [5] - engine weight to lift power is more favorable
  • Hp is astronomical (10000 HP) but weight is tiny (2000 lb)
• Motor weight to lift is 1:5 for light copter, and 1:25 for heavy cargo copters. HP to lift is 1:10 in the small copter, but 1:5 in the large - this is likely a function of aerodynamics of blades. Air is only so light, and can provide only so much lift.
  • It seems that multiple small blades are more effective at lift generation.
  • Seems a gasoline electric hybrid would provide the most lift per engine/'battery'=fuel weight