Air commodore is a one-star rank and a very senior flag rank officer, first of air ranks, being immediately senior to group captain and immediately subordinate to air vice-marshal. It has a NATO ranking code of OF-6 and is equivalent to a commodore in the Royal Navy or a brigadier in the British Army or the Royal Marines. Unlike these two ranks, however, it has always been a substantive rank. Additionally, air commodores have always been considered to be air officers whilst Royal Navy commodores have not since the Napoleonic Wars been classified as officers of flag rank, and British Army brigadiers have not been considered to be general officers since 1922 when they ceased to be titled as brigadier-generals. In other NATO forces, such as the United States Armed Forces and the Canadian Armed Forces, the equivalent one-star rank is brigadier general.