Narrative:

[I] was covering line call to a dhc-8-300 aircraft for brake wear pin not showing. Pressure was at 2800 psi. Let pressure down but went below 2000 psi and had to pump brakes back to 2000 psi and then checked brake wear pin. Talked to maintenance control to find out what they wanted to do because pin was not sticking out and forgot to put the pump handle back in place. When the aircraft arrived in ZZZ; maintenance went to change the brake and found the damage. [I] was trying to make on time departure. Line maintenance in ZZZ called maintenance control.I suggest always checking your work before leaving the aircraft; if you use something make sure it is back in its place before leaving the aircraft or going on to something else.

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Original NASA ASRS Text

Title: A Line Mechanic reports he forgot to stow the brake system handpump on a DHC-8-300 aircraft prior to departure. Aircraft was damaged. Distractions and efforts to make 'on-time' departure contributed to the situation.

Narrative: [I] was covering line call to a DHC-8-300 aircraft for brake wear pin not showing. Pressure was at 2800 psi. Let pressure down but went below 2000 psi and had to pump brakes back to 2000 psi and then checked brake wear pin. Talked to Maintenance Control to find out what they wanted to do because pin was not sticking out and forgot to put the pump handle back in place. When the aircraft arrived in ZZZ; Maintenance went to change the brake and found the damage. [I] was trying to make on time departure. Line Maintenance in ZZZ called Maintenance Control.I suggest always checking your work before leaving the aircraft; if you use something make sure it is back in its place before leaving the aircraft or going on to something else.

Data retrieved from NASA's ASRS site as of April 2012 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.