  We introduce a package service model where trucks as well as drones can
deliver packages. Drones can travel on trucks or fly; but while flying, drones
can only carry one package at a time and have to return to a truck to charge
after each delivery. We present a heuristic algorithm to solve the problem of
finding a good schedule for all drones and trucks. The algorithm is based on
two nested local searches, thus the definition of suitable neighbourhoods of
solutions is crucial for the algorithm. Empirical tests show that our algorithm
performs significantly better than a natural Greedy algorithm. Moreover, the
savings compared to solutions without drones turn out to be substantial,
suggesting that delivery systems might considerably benefit from using drones
in addition to trucks.
