Quality assessment and service damage detection for composite drive shafts

An in-situ quality assessment method for use with a drive shaft (DS) of an aircraft, the in-situ quality assessment method comprising:

• removing a portion of a cover structure of the aircraft to expose the DS;
• driving rotation of the DS about a longitudinal axis thereof at least at a sub-flight operation speed;
• infrared (IR) imaging of the DS during the rotating from a side of the DS;
• generating, from the IR imaging of the DS during the rotating, images of the DS including ring features appearing to extend circumferentially about the DS at longitudinal locations of local imperfections;
• and
• assessing a quality of the DS from the images.

An aircraft quality assessment assembly, comprising:

• an infrared (IR) imaging system comprising an IR camera;
• and
• an aircraft, comprising:
• a cover structure;
• an engine;
• main and tail rotors rotatably drivable by the engine;
• and
• a drive shaft (DS) by which torque and rotation are transmitted from the engine to the tail rotor,
• the IR camera being installed at a side of the DS within the cover structure, and
• the IR imaging system and the IR camera being configured to generate, with the DS being rotated about a longitudinal axis thereof by the torque and rotation at least at a sub-flight operation speed, images of the DS including ring features appearing to extend circumferentially about the DS at longitudinal locations of local imperfections.