Narrative:

The first officer returned to the cockpit from the walk around and stated there was a large pool of hydraulic fluid at the left main landing gear. The airplane had a carry forward maintenance item for that problem that was generated the day before. It appeared as though the problem had returned. I contacted maintenance on the VHF radio and made a log entry for the hydraulic leak. After an extended amount of time (maybe 20 minutes) we still had not heard from maintenance regarding the leak. I phoned maintenance again and was told that he was going to contact the line mechanics and find out the status for us. In the meantime I personally went down to inspect the leak and observed a pool of hydraulic fluid at the left main gear. Also; the main tires were saturated as well as the main landing gear assembly. When I returned to the cockpit a new maintenance release was printing that stated 'cleaned area no massive leak noted'. I questioned the release since I had just returned from looking at the landing gear personally. I called maintenance and stated the same to the maintenance controller and was told that he was told by the maintenance supervisor the airplane is good to go. I believe the station supervisors were being extremely pressured to get the airplane out on time. This belief is due to the observation of witnessing supervisors on the ramp pacing nervously as they observed the baggage loading; etc... Since I did not notice any drops while I was looking at the landing gear I trusted the mechanics. After arrival; line technicians were in the jetway and told me the airplane 'isn't going anywhere. You left a trail of hydraulic fluid all the way from the runway to the gate'. The first officer and I went down to inspect ourselves and in fact there was a trail as well as the tires and gear assembly being soaked with hydraulic fluid and witnessed hydraulic fluid leaking exactly the same as it was during preflight. It seems as though the personnel were being pressured to get the airplane out on time at any cost.

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Original NASA ASRS Text

Title: B757 crew discovers a hydraulic leak during preflight and is informed that it is minor and the flight will not be delayed for repairs. Upon arrival at destination the leak is significant and maintenance takes the aircraft out of service.

Narrative: The First Officer returned to the cockpit from the walk around and stated there was a large pool of hydraulic fluid at the left main landing gear. The airplane had a carry forward maintenance item for that problem that was generated the day before. It appeared as though the problem had returned. I contacted Maintenance on the VHF radio and made a log entry for the hydraulic leak. After an extended amount of time (maybe 20 minutes) we still had not heard from Maintenance regarding the leak. I phoned Maintenance again and was told that he was going to contact the Line Mechanics and find out the status for us. In the meantime I personally went down to inspect the leak and observed a pool of hydraulic fluid at the left main gear. Also; the main tires were saturated as well as the main landing gear assembly. When I returned to the cockpit a new Maintenance Release was printing that stated 'Cleaned area no massive leak noted'. I questioned the Release since I had just returned from looking at the landing gear personally. I called Maintenance and stated the same to the Maintenance Controller and was told that he was told by the Maintenance Supervisor the airplane is good to go. I believe the Station Supervisors were being extremely pressured to get the airplane out on time. This belief is due to the observation of witnessing Supervisors on the ramp pacing nervously as they observed the baggage loading; etc... Since I did not notice any drops while I was looking at the landing gear I trusted the Mechanics. After arrival; line technicians were in the jetway and told me the airplane 'Isn't going anywhere. You left a trail of hydraulic fluid all the way from the runway to the gate'. The First Officer and I went down to inspect ourselves and in fact there was a trail as well as the tires and gear assembly being soaked with hydraulic fluid and witnessed hydraulic fluid leaking exactly the same as it was during preflight. It seems as though the personnel were being pressured to get the airplane out on time at any cost.

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.