Final answer:
Munitions Item Managers would report a failed propellant stability test to the DDA by providing a detailed report on the test, results, and potential impacts.
Step-by-step explanation:
Munitions Item Managers would typically report to a DDA (Designated Department Authority) that a propellant failed its propellant stability test by following proper procedures and documentation. The DDA is responsible for overseeing the technical aspects of the munitions program, so the Item Manager would need to provide a detailed report on the failed propellant and any relevant information. This could include a description of the test conducted, the specific conditions and criteria for passing, the results obtained, and any potential impacts or risks associated with the failure.