Narrative:

The road not taken. We were cruising at FL410 when I noticed an EICAS message 'left hydraulic quantity.' I selected the status page and noticed that the left hydraulic quantity was reading .45 and decreasing. Since I was flying, I asked the first officer to get out our cockpit operating manual and follow the low hydraulic quantity procedures. I then noticed that the left hydraulic quantity was still falling and directed the first officer to go to the loss of left hydraulic quantity procedure. The fluid continued to decrease until it stopped at around .29. We reviewed the procedures and after calling and discussing the problem with dispatch and maintenance control, we decided to continue on to boston, since the leak had stopped and we still had good hydraulic quantity and pressure. No sooner had we gotten things under control, when the left hydraulic quantity started to drop again and this time it dropped all the way to zero. In rapid sequence we lost all the components associated with the left hydraulic system. We would not have autobrakes, nosewheel steering, automatic speed brakes and the left thrust reverser. We later discovered that we had to extend the flaps and landing gear with the alternate back up system. We started to look at our options. We declared an emergency with ZBW. Our destination (bos) was 30 mins away. It had long runways but strong xwinds. Bdl was 20 mins away, shorter runways than boston, slightly better xwinds. We were currently flying just south of albany, ny, which had shorter runways than the other two, but much better winds. We tried to contact our dispatch but were unable to communicate with them on the radio. I decided on albany, ny. We landed safely but as we stopped with less than 500 ft of runway left, I wondered if I had made the right decision to divert to albany. If there is a next time, I will take a few more mins to consider my options. Supplemental information from acn 592001: we began to prepare also for alternate flap and gear extension which we did on a long final to runway 1 at albany, wind was 290 degrees at 10 KTS. We opted for the longest runway with the crosswind, landing was hard, with steering difficulty, but brakes worked admirably.

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Original NASA ASRS Text

Title: DIVERSION TO AN ALTERNATE ARPT REQUIRED WHEN THE FLT CREW OF A B757-200 REALIZES THAT THE LOSS OF THEIR #1 HYD SYS REDUCES THEIR OPTIONS FOR CONTINUING ON TO THEIR DEST ARPT OF BOS, THEREFORE, DIVERTING INTO ALB, NY.

Narrative: THE ROAD NOT TAKEN. WE WERE CRUISING AT FL410 WHEN I NOTICED AN EICAS MESSAGE 'L HYD QUANTITY.' I SELECTED THE STATUS PAGE AND NOTICED THAT THE L HYD QUANTITY WAS READING .45 AND DECREASING. SINCE I WAS FLYING, I ASKED THE FO TO GET OUT OUR COCKPIT OPERATING MANUAL AND FOLLOW THE LOW HYD QUANTITY PROCS. I THEN NOTICED THAT THE L HYD QUANTITY WAS STILL FALLING AND DIRECTED THE FO TO GO TO THE LOSS OF L HYD QUANTITY PROC. THE FLUID CONTINUED TO DECREASE UNTIL IT STOPPED AT AROUND .29. WE REVIEWED THE PROCS AND AFTER CALLING AND DISCUSSING THE PROB WITH DISPATCH AND MAINT CTL, WE DECIDED TO CONTINUE ON TO BOSTON, SINCE THE LEAK HAD STOPPED AND WE STILL HAD GOOD HYD QUANTITY AND PRESSURE. NO SOONER HAD WE GOTTEN THINGS UNDER CTL, WHEN THE L HYD QUANTITY STARTED TO DROP AGAIN AND THIS TIME IT DROPPED ALL THE WAY TO ZERO. IN RAPID SEQUENCE WE LOST ALL THE COMPONENTS ASSOCIATED WITH THE L HYD SYS. WE WOULD NOT HAVE AUTOBRAKES, NOSEWHEEL STEERING, AUTO SPD BRAKES AND THE L THRUST REVERSER. WE LATER DISCOVERED THAT WE HAD TO EXTEND THE FLAPS AND LNDG GEAR WITH THE ALTERNATE BACK UP SYS. WE STARTED TO LOOK AT OUR OPTIONS. WE DECLARED AN EMER WITH ZBW. OUR DEST (BOS) WAS 30 MINS AWAY. IT HAD LONG RWYS BUT STRONG XWINDS. BDL WAS 20 MINS AWAY, SHORTER RWYS THAN BOSTON, SLIGHTLY BETTER XWINDS. WE WERE CURRENTLY FLYING JUST S OF ALBANY, NY, WHICH HAD SHORTER RWYS THAN THE OTHER TWO, BUT MUCH BETTER WINDS. WE TRIED TO CONTACT OUR DISPATCH BUT WERE UNABLE TO COMMUNICATE WITH THEM ON THE RADIO. I DECIDED ON ALBANY, NY. WE LANDED SAFELY BUT AS WE STOPPED WITH LESS THAN 500 FT OF RWY LEFT, I WONDERED IF I HAD MADE THE RIGHT DECISION TO DIVERT TO ALBANY. IF THERE IS A NEXT TIME, I WILL TAKE A FEW MORE MINS TO CONSIDER MY OPTIONS. SUPPLEMENTAL INFO FROM ACN 592001: WE BEGAN TO PREPARE ALSO FOR ALTERNATE FLAP AND GEAR EXTENSION WHICH WE DID ON A LONG FINAL TO RWY 1 AT ALBANY, WIND WAS 290 DEGS AT 10 KTS. WE OPTED FOR THE LONGEST RWY WITH THE XWIND, LNDG WAS HARD, WITH STEERING DIFFICULTY, BUT BRAKES WORKED ADMIRABLY.

Data retrieved from NASA's ASRS site as of July 2007 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.