The Airacuda was also saddled with a complex and temperamental electrical system and was the only aircraft ever built to rely on an independent auxiliary power unit (APU) to power both engine fuel pumps, as well as all aircraft electrical systems. Systems usually powered by an aircraft's engines were instead powered by the single generator. The generator, with its own supercharger, was located in the belly of the aircraft. In the event of a failure (and they occurred frequently), the crew was instructed to begin immediate emergency restart procedures as the aircraft basically shut down. When the APU failed, the pilot had "NO fuel pressure, NO vacuum, NO hydraulic pressure, NO gear, NO flaps and NO ENGINES".