[4] He joined the Navy as a Garde-Marine in 1741, and took part in the Battle of Toulon at Cape Sicié on 22–23 February 1744, serving on the 50-gun Diamant.

[4] On 2 April 1771, Chabert was given command of the frigate Mignonne, and conducted a cruise to test a chronometer made by Ferdinand Berthoud.

[10] From June to December 1776, he commanded the 32-gun frigate Atalante in an expedition to test marine chronometers and survey the coasts of Sicily and Greece.

[6] On 16 July, off the Mani Peninsula, near Koroni, pirates attacked Atalante with musket fire, and Chabert was gravely wounded when a bullet struck his left cheek and exited from under the ear.

[4][14] He later fought in the Invasion of Tobago in May and June 1781, and in the Siege of Brimstone Hill and subsequent capture of Saint Kitts in January and February 1782.

[16][5] Chabert was promoted to Chef d'Escadre on 12 January 1782 [4][17] The same year, he rose to Ordinary member of the Académie de Marine.

[18] In 1783, he authored a report about marine chronometers for the Académie des Sciences, a key element in the History of longitude.