Narrative:

The md-88 aircraft that I worked the night before had an air turn back. I was assigned the task of removing a borrowed flap actuator and replacing it with another air carrier's flap actuator. I did not bleed the [hydraulic] system the way it was stated in the aircraft maintenance manual (amm) because I was unable to view the whole content of the hyperlink at that time. I bled the pressure down without putting the bypass lever in the bypass position in the [main] gear wheel well. But I made sure there was not anyone onboard the aircraft or any power on the aircraft as well as using the 'out of service' tag. I also did not pin the main gears out. I was pressed for time and had not done that specific job on this aircraft before but had a pretty good idea and the amm reference to go by without the hyperlink for that one specific step where it states to put the bypass lever in the bypass position and pin the landing gears.

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Original NASA ASRS Text

Title: Two Line Maintenance Technicians report on their involvement with an MD-88 aircraft's Main Landing Gear (MLG) doors hydraulic bypass handle that was initially believed responsible for an air turnback.

Narrative: The MD-88 aircraft that I worked the night before had an air turn back. I was assigned the task of removing a borrowed flap actuator and replacing it with another Air Carrier's Flap Actuator. I did not bleed the [Hydraulic] System the way it was stated in the Aircraft Maintenance Manual (AMM) because I was unable to view the whole content of the hyperlink at that time. I bled the pressure down without putting the Bypass Lever in the bypass position in the [Main] Gear wheel well. But I made sure there was not anyone onboard the aircraft or any power on the aircraft as well as using the 'Out of Service' Tag. I also did not pin the Main Gears out. I was pressed for time and had not done that specific job on this aircraft before but had a pretty good idea and the AMM reference to go by without the hyperlink for that one specific step where it states to put the Bypass Lever in the bypass position and pin the Landing Gears.

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.