The Auster J/5 Adventurer is a British-built three-seat light high-wing monoplane of the late 1940s.

The Adventurer three-seat high-wing monoplane was developed from the J/1 Autocrat with extra power provided by the installation of the 130 h.p.

Gipsy Major engine, to enable more flexible operations in the hotter climate of Australia and New Zealand, where most examples were sold.

Unlike the similarly powered J/1 Aiglet and J/1N Alpha, the Adventurer retained the smaller tail surfaces of the Autocrat, the new engine being set back sufficiently far for the original fin area to remain sufficient.

[1] The prototype Adventurer was converted to the new standard from a J/1 Autocrat c/n 2093 and first flew on 15 November 1947.