What is a drone to you? If you are only thinking about multicopters when you hear that word then yes, those are not efficient and probably never will be.
But the term commonly refers to all unmanned aerial vehicles.
For example a Global Hawk unmanned aircraft can fly 14,000 nautical miles and remain aloft for 42 hours. They are by definition very efficient. That is a drone.
On the other end of the spectrum The Spirit of Butts' Farm crossed the atlantic with 118 US fluid ounces (3.5 L) of fuel. It was flying for ~39 hour and 1,881.6 mi (3,028.1 km). That is about 2045 mile per gallon if I count it right. That is very efficient, and of course since the aircraft was unmanned it is a drone.
> For example a Global Hawk unmanned aircraft can fly 14,000 nautical miles and remain aloft for 42 hours. They are by definition very efficient. That is a drone.
Wow - this is what they are planning to use to deliver packages?
But the term commonly refers to all unmanned aerial vehicles.
For example a Global Hawk unmanned aircraft can fly 14,000 nautical miles and remain aloft for 42 hours. They are by definition very efficient. That is a drone.
On the other end of the spectrum The Spirit of Butts' Farm crossed the atlantic with 118 US fluid ounces (3.5 L) of fuel. It was flying for ~39 hour and 1,881.6 mi (3,028.1 km). That is about 2045 mile per gallon if I count it right. That is very efficient, and of course since the aircraft was unmanned it is a drone.