Narrative:

This report is filed for the following incident: aircraft returned to gate for 'a' system hydraulic low pressure problem. The quick disconnect was found loose at the bottom of the 'a' reservoir. This was the originating flight following a maintenance check. When aircraft arrived; we inspected the tires/brakes which were within limits. As discussed previous; we then started to work. I started doing the servicing -- the exterior electrical motor driven pump and lube and preparation for back flush. After servicing both engines; I stated on the replacement of both electrical motor driven pump case drain filters for both hydraulic system a and B as required by the maintenance check. I did this in the following order/circumstances: 1) swapped ladder and tools to left wheel well to do an 'a' system side. 2) disconnected system 'a' electrical motor driven pump supply line quick disconnect. 3) right&right'ed system 'a' case drain filter and safetied drain bowl. Note: as I was beginning to safety the drain bowl; mr X came up and asked me how it was going. I said 'ok' and we started discussing an inspection for a spoiler repair. I said that I would be done in a few more minutes and we could take the ladder I was using to check out the spoiler. We both had doubts that the ladder was tall enough because of -700 wing height. I completed the safety wire on the drain bowl and immediately took ladder to the right wing where another technician was inspecting. I held the ladder while he stood on the ladder. He was able to get enough ht safety with just able to see something on inboard spoiler. He said he would have to go through cabin exit door to properly inspect the repair. I said ok; and took ladder back to front of aircraft. I then went back to left wheel well to get my tools; tub and cleaned area. I then accomplished other tasks as needed. As the maintenance drew to a close; we finalized the job with running both engines. We ran engines and was ground safety man. We started #1 engine first. I inspected the chip detectors and then the 'a' system case drain filter bowl for leaks. None noted. Note: when I checked the 'a' system case drain filter; I concentrated my light/inspection on the filter only with just a general glance inspection of the forward wheel well area. We accomplished same as step above on #2 engine chip detectors and 'B' system case drain filter bowl. After my shift ended; I was off for my normal scheduled days off. I returned to work and was notified by letter that a fact finding meeting was to be held because aircraft returned back to gate after the maintenance check the night before. I specifically remember connecting the 'B' system supply line quick disconnect because it gave me some trouble. I take full responsibility for my actions or lack of. At this time I believe that as I was completing up the safety wire on 'a' system case drain bowl; my mind got focused on the spoiler repair as discussed with mr X when he asked me how it was going.

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Original NASA ASRS Text

Title: A B737-700 RETURNED TO THE GATE DUE TO LOSS OF 'A' SYS HYD PRESSURE FROM THE ELECTRICAL MOTOR DRIVEN PUMP. FOUND 'A' SYS ELECTRIC MOTOR DRIVEN HYD PUMP SUPPLY LINE NOT CONNECTED.

Narrative: THIS RPT IS FILED FOR THE FOLLOWING INCIDENT: ACFT RETURNED TO GATE FOR 'A' SYS HYD LOW PRESSURE PROB. THE QUICK DISCONNECT WAS FOUND LOOSE AT THE BOTTOM OF THE 'A' RESERVOIR. THIS WAS THE ORIGINATING FLT FOLLOWING A MAINT CHK. WHEN ACFT ARRIVED; WE INSPECTED THE TIRES/BRAKES WHICH WERE WITHIN LIMITS. AS DISCUSSED PREVIOUS; WE THEN STARTED TO WORK. I STARTED DOING THE SVCING -- THE EXTERIOR ELECTRICAL MOTOR DRIVEN PUMP AND LUBE AND PREPARATION FOR BACK FLUSH. AFTER SVCING BOTH ENGS; I STATED ON THE REPLACEMENT OF BOTH ELECTRICAL MOTOR DRIVEN PUMP CASE DRAIN FILTERS FOR BOTH HYD SYS A AND B AS REQUIRED BY THE MAINT CHK. I DID THIS IN THE FOLLOWING ORDER/CIRCUMSTANCES: 1) SWAPPED LADDER AND TOOLS TO L WHEEL WELL TO DO AN 'A' SYS SIDE. 2) DISCONNECTED SYS 'A' ELECTRICAL MOTOR DRIVEN PUMP SUPPLY LINE QUICK DISCONNECT. 3) R&R'ED SYS 'A' CASE DRAIN FILTER AND SAFETIED DRAIN BOWL. NOTE: AS I WAS BEGINNING TO SAFETY THE DRAIN BOWL; MR X CAME UP AND ASKED ME HOW IT WAS GOING. I SAID 'OK' AND WE STARTED DISCUSSING AN INSPECTION FOR A SPOILER REPAIR. I SAID THAT I WOULD BE DONE IN A FEW MORE MINUTES AND WE COULD TAKE THE LADDER I WAS USING TO CHECK OUT THE SPOILER. WE BOTH HAD DOUBTS THAT THE LADDER WAS TALL ENOUGH BECAUSE OF -700 WING HEIGHT. I COMPLETED THE SAFETY WIRE ON THE DRAIN BOWL AND IMMEDIATELY TOOK LADDER TO THE R WING WHERE ANOTHER TECHNICIAN WAS INSPECTING. I HELD THE LADDER WHILE HE STOOD ON THE LADDER. HE WAS ABLE TO GET ENOUGH HT SAFETY WITH JUST ABLE TO SEE SOMETHING ON INBOARD SPOILER. HE SAID HE WOULD HAVE TO GO THROUGH CABIN EXIT DOOR TO PROPERLY INSPECT THE REPAIR. I SAID OK; AND TOOK LADDER BACK TO FRONT OF ACFT. I THEN WENT BACK TO L WHEEL WELL TO GET MY TOOLS; TUB AND CLEANED AREA. I THEN ACCOMPLISHED OTHER TASKS AS NEEDED. AS THE MAINT DREW TO A CLOSE; WE FINALIZED THE JOB WITH RUNNING BOTH ENGS. WE RAN ENGS AND WAS GND SAFETY MAN. WE STARTED #1 ENG FIRST. I INSPECTED THE CHIP DETECTORS AND THEN THE 'A' SYS CASE DRAIN FILTER BOWL FOR LEAKS. NONE NOTED. NOTE: WHEN I CHKED THE 'A' SYS CASE DRAIN FILTER; I CONCENTRATED MY LIGHT/INSPECTION ON THE FILTER ONLY WITH JUST A GENERAL GLANCE INSPECTION OF THE FORWARD WHEEL WELL AREA. WE ACCOMPLISHED SAME AS STEP ABOVE ON #2 ENG CHIP DETECTORS AND 'B' SYS CASE DRAIN FILTER BOWL. AFTER MY SHIFT ENDED; I WAS OFF FOR MY NORMAL SCHEDULED DAYS OFF. I RETURNED TO WORK AND WAS NOTIFIED BY LETTER THAT A FACT FINDING MEETING WAS TO BE HELD BECAUSE ACFT RETURNED BACK TO GATE AFTER THE MAINT CHK THE NIGHT BEFORE. I SPECIFICALLY REMEMBER CONNECTING THE 'B' SYS SUPPLY LINE QUICK DISCONNECT BECAUSE IT GAVE ME SOME TROUBLE. I TAKE FULL RESPONSIBILITY FOR MY ACTIONS OR LACK OF. AT THIS TIME I BELIEVE THAT AS I WAS COMPLETING UP THE SAFETY WIRE ON 'A' SYS CASE DRAIN BOWL; MY MIND GOT FOCUSED ON THE SPOILER REPAIR AS DISCUSSED WITH MR X WHEN HE ASKED ME HOW IT WAS GOING.

Data retrieved from NASA's ASRS site as of January 2009 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.