A rank in the RAF above warrant officer and below pilot officer.
空军候补飞行员（英国皇家空军一级准尉之上、少尉之下的军衔）
Example sentencesExamples
An Initial Training School was formed at Rongotai as a recruiting centre for pilots, observers, and air-gunners, and a course of thirty acting pilot officers began training on 20 September.
The Acting Pilot Officer was operating the RCAF Harvard training plane involved in the mid-air collision with a passenger plane.
As a non-graduate entrant, you might spend about a year as an acting pilot officer, followed by a year as a substantive pilot officer, and up to four years as a flying officer, before being promoted to flight lieutenant.