Situational Awareness; Training / Qualification
Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
Aircraft Aircraft Damaged; General Maintenance Action
Human Factors; Procedure
I completed a hydraulic A and B reservoir drain and filter change. AMT #2 was troubleshooting #2 engine fire loop issue and left to retrieve parts to affect a repair. After clearing tools and equipment used for the reservoir task; I proceeded to the cockpit to power the hydraulics and perform a leak check. These tasks were a part of a [routine] check so I deployed the flaps to perform a leak check and the flap inspection required. The initial lack of knowledge that an open thrust cowl interferes with the transition of the flaps; contributed to the incident.
A Maintenance Technician reported the trailing edge flaps were lowered and made contact with the open engine cowling.