Narrative:

Aircraft X; an A320; on final into ZZZ; selected 'gear down' and lost green system hydraulics. Aircraft was towed from runway to gate. A [hydraulic] leak was noted at the left main landing gear (medium large transport) down lock actuator flex hose; inboard of the two flex lines. A replacement line was shipped in from ZZZ1 and installed per aircraft maintenance manual 32-11-22 'installation of lock stay' actuator hose. After installation; hydraulics was serviced to required level and ran engines and operated flight controls to move hydraulics though green system. A functional test was required amm 32-31-00; but thought brace tool was gear safety collars and the functional test was completed. Green system hydraulics was again serviced to proper level. Aircraft released to service. [I] was called by our ZZZ maintenance manager that aircraft X had lost green system hydraulics's and was diverting to ZZZ2. [Realized] I misinterpreted a step in the functional test. Then looked into what this brace tool was. [Recommend]: 1) confer with more aviation maintenance technicians amts on understanding [amm] terminology. 2) this job; I have seen been accomplished and no problems occurred as this. 3) when I selected the amm reference; amm 32-31-00-710; this reference was right below the one I should have selected; amm 32-31-00-720.

Related reports:

Google
 

Original NASA ASRS Text

Title: A Line Mechanic reports that misunderstandings of terminology used in Airbus Aircraft Maintenance Manuals (AMM) compared to Boeing AMMs and the lack of an Airbus Brace Tool led to an A320 diversion due to low Green System hydraulic fluid. A hydraulic flex hose to the Lock Stay; Down Lock actuator on the left Main Gear had broken on a previous flight.

Narrative: Aircraft X; an A320; on Final into ZZZ; selected 'Gear Down' and lost Green System hydraulics. Aircraft was towed from runway to Gate. A [hydraulic] leak was noted at the left Main Landing Gear (MLG) Down Lock actuator flex hose; inboard of the two flex lines. A replacement line was shipped in from ZZZ1 and installed per Aircraft Maintenance Manual 32-11-22 'Installation of Lock Stay' actuator hose. After installation; hydraulics was serviced to required level and ran engines and operated flight controls to move hydraulics though Green System. A Functional Test was required AMM 32-31-00; but thought brace tool was gear safety collars and the Functional Test was completed. Green System hydraulics was again serviced to proper level. Aircraft released to service. [I] was called by our ZZZ Maintenance Manager that Aircraft X had lost Green System hydraulics's and was diverting to ZZZ2. [Realized] I misinterpreted a step in the Functional Test. Then looked into what this brace tool was. [Recommend]: 1) Confer with more Aviation Maintenance Technicians AMTs on understanding [AMM] terminology. 2) This job; I have seen been accomplished and no problems occurred as this. 3) When I selected the AMM reference; AMM 32-31-00-710; this reference was right below the one I should have selected; AMM 32-31-00-720.

Data retrieved from NASA's ASRS site as of July 2013 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.