of potential infiltration. Example is the OA-10A, an attack aircraft modified to provide observation of enemy territory. P Patrol. Similar to the basic mission symbol, P applies to aircraft modified to perform maritime patrol. Q Drone. Applies to craft modified to operate unmanned, under control of ground or air directors or autonomously. Example is the QF-106 Delta Dart, a fighter modified to fly under remote control as a target for missile testing. R Reconnaissance. Similar to the basic mission symbol, R applies to aircraft modified to perform air reconnaissance of enemy forces, territory, and facilities. Example is the RF-5E Tiger II, a fighter with added reconnaissance cameras and equipment for photographing enemy positions. S Anti-Submarine. Similar to the basic mission symbol, S applies to aircraft modified to search for, locate, and attack enemy submarines like the SZ-1A T Training. Similar to the basic mission symbol, T applies to aircraft modified for use as trainers, both initial and operational. Examples are two-seat operational training versions of single-seat aircraft, such as the TA-4J and TF-102. Fully combat-capable two-seaters are usually simply assigned a new series letter. U Utility. Similar to the basic mission symbol, U applies to aircraft modified to allow use as utility and base support aircraft. An example is the UC-12B, modified for utility by adding a cargo door. V Staff/VIP. Applied to aircraft modified for transport of staff and ranking personnel with furnishment of comfortable accommodations. Example is the VC-25, a 747 modified to serve as the Presidential transport, or Air Force One. W Weather. Applied to aircraft modified for weather monitoring and air sampling to detect nuclear, biological, and chemical contamination and for intelligence gathering on foreign nuclear testing. An example is the WC-135. Basic mission symbol The basic mission symbol is the heart of the mission part of the designation. No designation is without it, and some designations consist of only a basic mission symbol for the mission part, such as the F-14 or C-130. The following are the officially authorized basic mission symbols: A Attack. Attack craft are designed to directly attack enemy land or sea targets, interdict enemy movements and support, and strike precision targets. Examples are the A-6 Intruder and A-10 Thunderbolt II. B Bomber. Bombers are designed to attack strategic and tactical targets with heavy bomb loads and missiles. They carry heavy loads of free-fall and stand-off weaponry. Examples are the B-52 Stratofortress