We consider the problem of a single Unmanned Aerial Vehicle (UAV) routing
problem where there are multiple depots and the vehicle is allowed to refuel
at any depot. The objective of the problem is to find a path for the UAV such
that each target is visited at least once by the vehicle, the fuel constraint is
never violated along the path for the UAV, and the total fuel required by
the UAV is a minimum. We develop an approximation algorithm for the
problem, and propose fast construction and improvement heuristics to solve
the same. Computational results show that solutions whose costs are on an
average within 1.4% of the optimum can be obtained relatively fast for the
problem involving 5 depots and 25 targets.