Like earlier carriers, The Ford has four launch catapults so that (theoretically), should one fail, the ship could continue operations using the remaining three. But the Navy found there is no way to electrically isolate each EMALS catapult from the others during flight operations, raising questions about the system’s operational suitability. The massive electrical charge needed to power the catapults is stored in three Energy Storage Groups, each using four heavy flywheel-generators. The three groups together power all four catapults and cannot be electrically disconnected from a single failed catapult to allow repairs while the other three catapults launch planes.
This means that repairing the failed catapult must wait until all flight operations have been completed, or, in the event that multiple launchers fail, all flights may have to be suspended to allow repairs. Thus there is the possibility that the ship might not be able to launch any planes at a critical moment because the EMALS designers failed to provide independent power for each of the four catapults.
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And, in an astonishing design oversight exactly like that of the EMALS, General Atomics engineers made it impossible to repair AAG failures without shutting down flight operations: the AAG power supply can’t be disconnected from the high-voltage supply while flights continue.
