and MQ-9 drones. G Glider. A glider is a fixed-wing aircraft designed to use air currents for normal lift, although it may have an engine. An example is the TG-15A training glider. H Helicopter. A helicopter is any rotary-wing aircraft, like the UH-60. Q Unmanned. An unmanned aerial vehicle (UAV) is any aircraft without capacity for a human pilot, but not applied to missiles or rockets. Examples include MQ-1 Predator and RQ-11. S Spaceplane. A spaceplane is a vehicle designed to fly beyond earth's atmosphere and return. This vehicle code was poorly chosen, as it conflicts with the mission code S (Anti-Submarine Warfare). "ES" could equally designate a spaceplane designed specifically for electronic warfare or an anti-submarine plane modified for that purpose. V V/STOL. A Vertical and/or Short Takeoff and Landing aircraft is designed to take-off and land vertically, but not rely on rotary-wing lift for flight. This includes vectored thrust aircraft such as the AV-8 Harrier and tiltrotors such as the V-22 Osprey. It also applies to aircraft of the normal fixed-wing configuration that are capable of taking off and landing in a short runway space, such as the OV-10 Bronco. Z Lighter than air. A lighter than air craft is designed to remain aloft through buoyancy of lighter than air gases. Such craft include blimps and balloons. An example is the SZ-1A. Design number The design number is separated from the earlier components by a dash. Design numbers run consecutively from 1 to 999. Series The series letter follows the design number and progresses consecutively starting with A. In the event the series letter "Z" is used, the design number will progress to the next unused number and series will begin again at "A". To avoid confusion, series "I" and "O" are not used. Additional Components Configuration/Component number Configuration/component numbers signify changes that "affect performance, tactics, or integral components of a weapon system." They appear to the right of the series symbol and are separated from the series symbol by a dash. Block number The block number specifies a group of aircraft produced to the same specifications by the manufacturer. Block numbers are assigned in multiples of 5 (01, 05, 10). An example is F-16C Block 25. Serial number Serial numbers are located on the tail and identify a specific aircraft. For example, MH-53M Pave Low IV serial number 68-10357 was the Pave Low which carried the mission