A unit of two to four squadrons, commanded by a lieutenant colonel, colonel, commander, naval captain or an equivalent rank. The United States Air Force (USAF), groupes of the French Armée de l'air, gruppen of the German Luftwaffe, United States Marine Corps Aviation,[1] British Fleet Air Arm and some other naval air services usually follow this pattern.[citation needed] A larger formation, often comprising more than 10 squadrons, commanded by a major general, brigadier general, commodore, rear admiral, air commodore or air vice-marshal. The air forces of many Commonwealth countries, such as the British Royal Air Force (RAF), follow this pattern.