A Lead Mechanic; Maintenance Inspector and Maintenance Supervisor report on their involvement with an ATR-72-200 aircraft that was found with incorrectly installed right aileron attach bolts; prior to flight.

Narrative

Right aileron mounting hardware installed incorrectly. I overheard the mechanics talking about how they thought the attach bolts for the right-hand aileron were installed incorrectly. I later heard that the installation of the right aileron had been signed off by Quality Assurance Department. I believe this event happened because there were too many people involved in the job. Event detected during inspection prior to closing access panels. The aircraft was brought back to the hangar area and the attach hardware was installed correctly. There should not be so many mechanics working the same task. Supplemental information from ACN 832004: I was the Inspector overseeing 3 mechanics installing right-hand aileron on Aircraft X. They properly torqued hardware and cotter pin as stated on Job Card 57-61-00. In the morning 2 days later; I was called and informed that the AC flight count factor was canceled and was returning to hangar; to re-inspect aileron bolts installation. Conflict with job card. Supplemental information from ACN 832005: I was made aware of the situation; stopped the flight count factor; and corrected the problem before the flight. Suspect wrong interpretation of the manual. Maintenance personnel told me.