Perhaps the most common form of nesting in aircraft design is the retractable undercarriage (seeing relatively limited use in small unmanned aircraft due to its relatively high cost and complexity) - but are there other forms of nesting worth considering at the layout stage?
• Telescopic components - would a telescopic boom or fuselage facilitate transportation of the aircraft?
• Telescopic wings could allow in-flight variation of the span. This could be useful either in allowing multiple roles the aircraft can switch between in flight (short, stubby wings for high-speed dash to station and extended high-aspect-ratio wings for low-speed, high-efficiency loiter on station) or simply to facilitate transportation and storage.
• Could the whole airframe be laid out such that it would facilitate the stacking of multiple airframes of the same layout? This may have the aim of optimizing the utilization of hangar floor space or, perhaps, in the case of small UAVs launched from a mother ship or a balloon, optimizing the volumetric utilization of the storage space on board the launch aircraft.
• Could a payload (e.g., an atmospheric science instrument) be stored inside the aircraft but attached to the end of a line that can be reeled in and out of the aircraft to ensure that it can take its measurements in the freestream, unaffected by the aircraft itself (like the trailing cone used for static pressure measurement in flight testing)?