1. An imaging method for capturing images using a sensor mounted on an unmanned aircraft, the method comprising: acquiring, by one or more processors, a specification of possible positions and orientations relative to the aircraft to which the sensor may be moved; acquiring, by the one or more processors, a specification of the manoeuvrability of the aircraft; acquiring, by the one or more processors, a specification of a linear path along the ground; using the specification of the manoeuvrability of the aircraft and the specification of the path, determining, by the one or more processors, that the path includes a portion having a radius of curvature that is smaller than a minimum turning radius of the aircraft; using the specification of the possible positions and orientations of the sensor relative to the aircraft, the specification of the path, and the specification of the manoeuvrability of the aircraft, determining, by the one or more processors, a route for the aircraft to follow and an imaging schedule for the sensor, wherein determining the route comprises, responsive to determining that the path includes a portion having a radius of curvature that is smaller than a minimum turning radius of the aircraft, including, in the route, a loop; following, by the aircraft, the route; and whilst the aircraft follows the route, performing, by the sensor, the imaging schedule including the sensor moving with respect to the aircraft such that, for each point along the path, that point is coincident with a footprint of the sensor on the ground for at least some time during the procedure, and the sensor capturing images such that each point along the path is present within at least one of the captured images; wherein the portion of the path that has a radius of curvature that is smaller than a minimum turning radius of the aircraft is imaged as the aircraft flies along the loop.