Turn and Slip Indicator 2 Minute Turn, Type MD-4A, MIL-I-7627A C-46 as there are no scratches

as there are no scratches or wear marks

Beam Displacement Scale

A-26 Invader

The manual covers instruments that were eventually used in aircraft of the Air Corps US Army and Air Force US Army during WWII

Turn and Slip Indicator 2 Minute Turn, Type MD-4A, MIL-I-7627A C-46 as there are no scratchesThis Turn and Slip Indicator Type MD 4A, MS28041, MIL I 7627A, 2 minute turn, was made by RC Allen. The case is open, and the internal mechanism can be removed to reveal the electrical gyroscope. Likely from the 1960s. It is in experienced condition given its age. The dial markings are clear and the glass is intact. Measures 2. 25inches diameter by ~5inches deep.