What These Military Aircraft Designations Stand For

It’s relatively straightforward for aviation enthusiasts to identify the roles of certain military aircraft based on their designations. For example, the “F” in F-16 and the “B” in B-2 Spirit clearly indicate the primary roles of these aircraft. However, not all aircraft follow such designations. Russian-built fighters, for example, are named after their manufacturers, such as the Su-27 from Sukhoi and the MiG-29 from Mikoyan-Gurevich. European military aircraft also do not adhere to these designations, as seen with the Panavia Tornado and Eurofighter Typhoon, which do not reveal their roles through their names.

Here, then, is a list of the meanings behind the designations of US military aircraft. It’s important to note, however, that not all manufacturers adhere to these designations.

Core Designations

• G – Glider: While not used by the main Air Force, the designation exists for gliders used by cadets at the Air Force Academy. Examples include the TG-15A and TG-15B (Schempp-Hirth Duo Discus and Discus 2) and the TG-16 (DG Flugzeugbau DG-1000S).
• H – Search And Rescue: Primarily used by the Coast Guard, the “H” designation signifies aircraft dedicated to search and rescue (SAR) operations for distressed personnel, ships, or aircraft. While most SAR aircraft are helicopters, some militaries use “H” for helicopters in general (e.g., the UK’s Sea King HAS.2).
• K – Tanker: Modern warfare often necessitates refueling aircraft mid-flight to extend their range. Large cargo aircraft like the C-135, modified as aerial tankers with the “K” designation (e.g., KC-135 Stratotanker), provide this critical capability.
• M – Multi-Mission: These aircraft support US special forces by performing infiltration, exfiltration, and resupply missions behind enemy lines. The most common example is the Lockheed MC-130 series, with variants dedicated to various special forces operations.
• O – Observation: One of the oldest military uses of aircraft, the “O” designation signifies unarmed aircraft used for observation and reconnaissance purposes, primarily gathering visual intelligence. The sole remaining “O” designated aircraft in the US military is the OC-135B, a modified C-135 used for observation under the Open Skies Treaty.
• P – Maritime Patrol: Similar to the “O” designations used over land by the Army and Air Force, the Navy employs “P” designated aircraft for maritime patrol, including anti-submarine warfare, surface reconnaissance, and search and rescue at sea. Examples include the P-8 Poseidon, a powerful maritime patrol aircraft. It’s important to note that this is different from World War II fighters like the P-51 Mustang and P-47 Thunderbolt, which actually stands for “Pursuit.”
• Q – Unmanned Aerial Vehicle (UAV): Drones, or UAVs, have become a significant part of modern warfare. The US military operates various UAVs with “Q” designations, including the MQ-1 Predator, MQ-9 Reaper, and MQ-1C Gray Eagle, used for reconnaissance and combat missions.

• U – Utility: These versatile workhorses of the military perform various roles, including troop and equipment transport, medical evacuation, and light observation. The iconic UH-60 Black Hawk helicopter and the UC-35 utility aircraft are prime examples.
• V – VIP Transport: These specially modified aircraft transport VIPs, including government and military officials, often featuring advanced communication systems and enhanced security measures. The most famous example is the Boeing VC-25A, better known as Air Force One.
• W – Weather Reconnaissance: While largely replaced by satellites, some militaries still operate “W” designated aircraft for weather reconnaissance, typically modified cargo or bomber aircraft equipped with specialized data collection instruments. Examples include the WC-130J Hurricane Hunters and WC-135 Constant Phoenixes.

Multi-Letter Designations

Some aircraft designations incorporate multiple letters to signify modifications for a different purpose than their original design. For instance, the RC-135 Rivet Joint (Reconnaissance Cargo) is a modified C-135 transport aircraft used for reconnaissance.

Not all multi-letter designations follow this strict modification logic. The F/A-18 Hornet, for example, is solely an attack aircraft, despite the slash suggesting a fighter-attack role. This designation arose from plans for both fighter and attack variants of the same aircraft, with the “F/A-18” remaining even after the fighter variant was shelved.

In some exceptional instances, the official designation of an aircraft doesn’t accurately reflect its primary role, as is the case with the Lockheed F-117 Nighthawk. Despite being labeled with an “F” for fighter, the F-117 is, in fact, an attack aircraft, specialized in stealth and precision striking capabilities. This misleading designation was a strategic decision by the U.S. Air Force, aimed at concealing the aircraft’s true mission and abilities for security reasons during its introduction. The choice of “F-117” as its designation was deliberately made to confuse the Soviet Union and other potential foes, masking the aircraft’s real purpose and enhancing operational secrecy.