The squadron was first organized in February 1943 at Page Field, Florida as the fourth squadron of the 53d Fighter Group.
 It was initially equipped with Bell P-39 Airacobras, but before the year was over, switched to training pilots with the Republic P-47 Thunderbolt.
The squadron was an Replacement Training Unit, an oversized unit whose mission was to train individual pilots.

However, the Army Air Forces found that standard military units like the 438th, based on relatively inflexible tables of organization were not well adapted to the training mission.
 Accordingly, it adopted a more functional system in which each base was organized into a separate numbered unit, manned according to the base's mission.
 The 53d Group and its two squadrons at Page Field, along with supporting units there were disbanded and replaced by the 338th AAF Base Unit (Replacement Training Unit, Fighter) in May 1944.
The squadron was first organized in February 1943 at Page Field, Florida as the fourth squadron of the 53d Fighter Group.  It was initially equipped with Bell P-39 Airacobras, but before the year was over, switched to training pilots with the Republic P-47 Thunderbolt. The squadron was an Replacement Training Unit, an oversized unit whose mission was to train individual pilots.
However, the Army Air Forces found that standard military units like the 438th, based on relatively inflexible tables of organization were not well adapted to the training mission.  Accordingly, it adopted a more functional system in which each base was organized into a separate numbered unit, manned according to the base's mission.  The 53d Group and its two squadrons at Page Field, along with supporting units there were disbanded and replaced by the 338th AAF Base Unit (Replacement Training Unit, Fighter) in May 1944.
438th Fighter-Interceptor Squadron