|Date of Birth:||c. 1793|
|Billets:||Loch Laggan covert, lookout for Temeraire|
Allen was a young lookout for Temeraire, barely twelve years old in late 1805. He was a cadet when William Laurence first added him to the crew, but soon made ensign. He travelled with the rest of the crew to China and to Africa.
Allen was notable for his clumsiness, which never quite managed to get him killed. Keynes's frequent reprimands suggest that he became nauseous easily, and on at least one occasion he had to be reprimanded by Lt. Ferris for attempting to bring a flask of liquor aboard.
During Iskierka's hatching, when Temeraire realized that he was about to lose his first lieutenant, John Granby, to be captain to the hatchling, he suggested giving the hatchling Allen instead. This suggests that Temeraire considered Allen the least desirable member of the crew.
When Laurence was convicted of treason in late 1807, all of Temeraire's crew members were reassigned. Allen was assigned not to another dragon, but to the clerks. When Laurence - technically still under a death sentence - and Temeraire rejoined the Aerial Corps during Napoleon's occupation of Britain, Allen was one of the few former crew members who returned. Despite his clumsiness, he was determined to serve on the front lines.