In military terms, 4 Squadron, IV Squadron or 4th Squadron may refer to:
; Aviation squadrons :
*
No. 4 Squadron RAAF
No. 4 Squadron is a Royal Australian Air Force squadron composed of the air force special forces Combat Controllers, aircrew who operate the Pilatus PC-21 aircraft and instructors for the Australian Defence Force Joint Terminal Attack Controll ...
, a unit of the Royal Australian Air Force
*
No. 4 Squadron (India)
No. 4 Squadron IAF (Oorials) is a fighter squadron of the Indian Air Force (IAF) equipped with the Mikoyan-Gurevich MiG-21, MiG-21 Bison, based at Uttarlai Air Force Station in Uttarlai in Barmer, Rajasthan, India. Since its establishment during ...
, a unit of the Union of India Air Force
*
No. 4 Squadron RNZAF
No. 4 Squadron RNZAF was a Royal New Zealand Air Force (RNZAF) patrol bomber unit that served in the South Pacific during World War II.
In the 1950s it also served as a Territorial Air Force unit flying Harvards and Mustangs from Taieri in Ota ...
, a unit of the Royal New Zealand Air Force
*
4 Squadron SAAF, a unit of the South African Air Force
*
No. IV Squadron RAF, a unit of the United Kingdom Royal Air Force
*
4th Aero Squadron
Fourth or the fourth may refer to:
* the ordinal form of the number 4
* ''Fourth'' (album), by Soft Machine, 1971
* Fourth (angle), an ancient astronomical subdivision
* Fourth (music), a musical interval
* ''The Fourth'' (1972 film), a Sovie ...
, later 4th Squadron (Observation), 4th Observation Squadron, 4th Reconnaissance Squadron, a unit of the United States Air Corps
*
4th Fighter Squadron (United States), a unit of the United States Air Force
*
4th Space Control Squadron (United States), a unit of the United States Air Force
*
4th Space Operations Squadron (United States), a unit of the United States Air Force
*
HS-4
Helicopter Sea Combat Squadron Four (HSC-4) (previously Helicopter Anti-Submarine Squadron Four (HS-4)), also known as the Black Knights, is a multi-role combat helicopter squadron of the United States Navy based at Naval Air Station North Island ...
(Helicopter Anti-Submarine Squadron 4), a unit of the United States Navy
*
VMAQ-4 (Marine Tactical Electronic Warfare Squadron 4), a unit of the United States Marine Corps
; Naval squadrons :
*
4th Battle Squadron (United Kingdom)
The 4th Battle Squadron was a squadron of the British Royal Navy consisting of battleships. The 4th Battle Squadron was initially part of the Royal Navy's Home Fleet (1912–14) and then the Grand Fleet after the outbreak of the First World Wa ...
, a formation of the United Kingdom Royal Navy
*
Submarine Squadron 4 (United States), a formation of the United States Navy
; Ground combat squadrons :
*
2/4th Cavalry Commando Squadron (Australia)
The 2/4th Commando Squadron was one of 12 independent companies and commando squadrons raised by the Australian Army during the Second World War. Raised in August 1941, it was disbanded not long after due to conceptual problems, but it was qui ...
, a unit of the Australian Army
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