Narrative:

Just prior to entering ETOPS airspace on a transatlantic flight; the left hydraulic quantity went rapidly to 45% and then to 22-21% and stabilized. We followed QRH procedures; contacted maintenance control via ACARS and coordinated a return to the departure airport with ATC. We also turned on engine anti-ice; started the APU; and descended to a lower altitude all in an attempt to burn extra fuel; thereby reducing our landing weight. Configuring early to determine operating capability of landing gear and flaps helped to bring us within 2;000 pounds of max landing weight. Upon extension of about 20 degrees of flaps and especially after gear extension; the aircraft began to 'shudder' noticeably. We also had a spoilers EICAS message appear in amber shortly after beginning to configure. We had been directed by maintenance control to turn off the left engine-driven and electric pumps upon initial contact with them. Turning pumps back on eliminated message and vibration. Landing [was normal with] vertical speed less than 100 FPM; as was nose wheel steering and taxiing back to the gate. Old airplanes; shoddy maintenance practices; and management's blatant disregard for safety and 'on-time' departure pressure [are to blame]. Those meeting us upon return were professional and concerned; but this was something out of their control.

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Original NASA ASRS Text

Title: A B757 returned to the departure airport after the left hydraulic system quantity dropped to 21%. A hydraulic leak was discovered in the left engine pylon.

Narrative: Just prior to entering ETOPS airspace on a transatlantic flight; the left hydraulic quantity went rapidly to 45% and then to 22-21% and stabilized. We followed QRH procedures; contacted Maintenance Control via ACARS and coordinated a return to the departure airport with ATC. We also turned on engine anti-ice; started the APU; and descended to a lower altitude all in an attempt to burn extra fuel; thereby reducing our landing weight. Configuring early to determine operating capability of landing gear and flaps helped to bring us within 2;000 LBS of max landing weight. Upon extension of about 20 degrees of flaps and especially after gear extension; the aircraft began to 'shudder' noticeably. We also had a SPOILERS EICAS message appear in amber shortly after beginning to configure. We had been directed by Maintenance Control to turn off the left engine-driven and electric pumps upon initial contact with them. Turning pumps back on eliminated message and vibration. Landing [was normal with] vertical speed less than 100 FPM; as was nose wheel steering and taxiing back to the gate. Old airplanes; shoddy maintenance practices; and Management's blatant disregard for safety and 'on-time' departure pressure [are to blame]. Those meeting us upon return were professional and concerned; but this was something out of their control.

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.