B737-800
Maintenance Airframe; Maintenance Powerplant
Communication Breakdown; Confusion; Situational Awareness; Distraction
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
Aircraft Aircraft Damaged; General Maintenance Action
Aircraft
[Mechanic] and myself were working on Aircraft X. We were doing an initial evaluation on the right wing inboard spoiler actuator leaking at return line b-nut; we did not know what we had so we raised the spoilers and placed a rubber chock under the spoiler. We didn't know if the spoilers would lose pressure because of the leak; we did not want the spoiler to close while we were tightening the b-nut. I went up to the flight deck to turn off the hydraulics. Out of habit; I put the speed brake handle down; and then turned off the hydraulics. The damage was done.
While performing a hydraulic leak evaluation on Aircraft X RH IB (Right Hand Inboard) spoiler it was damaged. [Mechanic] and I were trying to determine if a B-nut on the spoiler actuator was the cause. We put a rubber chock under the spoiler to give an added security if the spoiler crept down when hydraulic pressure was removed. In my experience; this was a standard practice to prevent the spoiler from drooping and allow your hand to be in under the spoiler safely. During the process; the spoilers were retracted under hydraulic power inadvertently sandwiching the chock under the spoiler.The spoiler lever was inadvertently retracted; instead of the hydraulic power being removed and the lever remaining in the extended position.[Better procedure is to] extend the trailing edge flaps to full so that access is available from the underside of the wing from a safe position.
Maintenance Technician reported inadvertently activating spoilers while a rubber chock was in place; damaging the spoiler.