Overview
Sub-lieutenant is usually a junior officer rank, used in armies, navies and air forces.
In most armies, sub-lieutenant is the lowest commissioned officer rank. However, in Brazil, it is the highest non-commissioned rank, and in Spain, it is the second highest non-commissioned rank.
As a naval rank, a sub-lieutenant ranks below a lieutenant.
Armies and air force rank
In France, a sub-lieutenant is the junior commissioned officer in the army or the air force. He wears a band in the colour of his corps (e.g. gold for infantry, silver for armoured cavalry, etc.). During the 18th century a rank of existed in the French Navy. It was the equivalent of the master's mate rank of the Royal Navy. It is now replaced by the rank of "first ensign".
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