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Attributes | |
ACN | 321618 |
Time | |
Date | 199511 |
Day | Sun |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | airport : lhr |
State Reference | FO |
Altitude | agl bound lower : 0 agl bound upper : 0 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tower : tus |
Operator | common carrier : air carrier |
Make Model Name | B747-100 |
Operating Under FAR Part | Part 121 |
Navigation In Use | Other |
Flight Phase | ground other : taxi |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : instrument pilot : commercial pilot : atp pilot : flight engineer |
Experience | flight time last 90 days : 220 flight time total : 15800 flight time type : 4492 |
ASRS Report | 321618 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : instrument pilot : flight engineer pilot : commercial pilot : atp pilot : private |
Experience | flight time last 90 days : 150 flight time total : 9000 flight time type : 110 |
ASRS Report | 321699 |
Events | |
Anomaly | conflict : ground critical other anomaly other |
Independent Detector | other flight crewa |
Resolutory Action | none taken : detected after the fact none taken : insufficient time |
Consequence | other |
Supplementary | |
Primary Problem | Flight Crew Human Performance |
Air Traffic Incident | Pilot Deviation |
Narrative:
From entry point of gate xx at lhr, while taxiing on #1 and #4, we located the stop point in a block of 6 aircraft. Normal stop and line-up so seat belt sign was turned off and #4 shut down. Inoperative APU so we waited for ground power. After 3 mins we still had no ground power, neither cabin nor cargo doors were open, jetways were not moving, and the accu-park lights were still on. I looked again at the stop block and noticed stopline below the B747, then looked to the next block to left seeing another B747 below 2 other aircraft. Since we were well short and nothing was happening to secure aircraft, I told the crew I would try to taxi forward on 1 engine and made an announcement to passenger to hold onto a seat. Placed thrust to approximately 30 percent N1 and aircraft eased forward. As we approached the actual B747 stop bar, I eased on some brake with no response, so I added more brake with no response, so I put the brakes to the floor, again no response. I yelled to crew, 'no brakes -- give me pressure.' so responded while I switched brake source to #2 with no response so I capped the #2 brake switch and asked so to select system 1 at the same time first officer reached over and pulled #1 into reverse thrust. At this point we were slowing but had no directional guidance. As pressure came up on #1, aircraft stopped. Noting full pressure, I reset brakes waiting for ground since we were 18-24 inches from impacting jetway with #2 engine. Ground mechanic called on interphone indicating they would push us away from forward jetway that was against aircraft. Push was accomplished, brakes were set, and passenger deplaned. Suggestions: 1) attempt to standardize accu-park system to avoid confusion. 2) B747 SOP could include a statement to leave #2 and #4 adp's on until last engine is shut down. 3) accu-park lights should be turned off to signal crew, stop taxi. Callback conversation with reporter revealed the following information: reporter was called to inquire as to what he might do differently the next time this situation should occur. Reporter stated that he would make certain the air driven pumps would not be turned off until all engines had been shut down. The checklist for shutdown says to turn off all hydraulic pumps when engines are shut down but common practice is to shut down hydraulic pumps when each respective engine is shut down and not wait until all engines are shut down. Reporter also counted on at least 3 good brake applications from the brake hydraulic accumulator, but that pressure application had already been bled off during the stopping of the aircraft at the early stop point. Reporter has seen no changes in procedures come from the training department since this incident. Nor has any other official said anything regarding this incident. Reporter did say the first officer's actions are what stopped the aircraft from further movement forward when he put the #1 engine in reverse. Damage to the aircraft was a 6-INCH dent into the fuselage. Supplemental information from acn 321699: we did not notice that we were short of our B747 gate until after shutting #2, #3, and #4 engines down and turning off seat belt sign. Captain turned seat belt sign back on and made an announcement. I began to call operations to get towed in. Captain pushed up power and we moved forward. The captain tried to stop and his brakes did not work (so had turned all hydraulic pumps off). I tried my brakes and they did not work either. The captain and so worked on the hydraulic problem as we continued forward. I put the #1 engine into reverse to stop us. I think that if you stop at gate, you should get towed forward if you have to move again. Someone under the aircraft could have been hurt. Callback conversation with reporter acn 321699 revealed the following information: reporter was flying as first officer. He added the following information to the NASA ASRS reports already filed: the captain and so joined himself at a required company conference call to determine what might be done differently so this type of incident will not happen again. Reporter was strongly in favor of not moving an aircraft which has stopped and shut down engines unless a ground tug driver hooks up and moves the aircraft. The company involved seemed to agree with him and is now working to make that the mandatory procedure. The preferred procedure will evidently take some time to implement as the ground services in england are slow to comply with any procedures that are changed. Reporter feels confident that standard procedure will be to move aircraft only by ground tug when small movements of aircraft are needed. Reporter also stated that his putting #1 engine into reverse is what stopped the aircraft movement.
Original NASA ASRS Text
Title: FLC TAXI ACFT FORWARD TO ADJUST STOPPING POINT ON 1 ENG. ACFT RUNS INTO JETWAY.
Narrative: FROM ENTRY POINT OF GATE XX AT LHR, WHILE TAXIING ON #1 AND #4, WE LOCATED THE STOP POINT IN A BLOCK OF 6 ACFT. NORMAL STOP AND LINE-UP SO SEAT BELT SIGN WAS TURNED OFF AND #4 SHUT DOWN. INOP APU SO WE WAITED FOR GND PWR. AFTER 3 MINS WE STILL HAD NO GND PWR, NEITHER CABIN NOR CARGO DOORS WERE OPEN, JETWAYS WERE NOT MOVING, AND THE ACCU-PARK LIGHTS WERE STILL ON. I LOOKED AGAIN AT THE STOP BLOCK AND NOTICED STOPLINE BELOW THE B747, THEN LOOKED TO THE NEXT BLOCK TO L SEEING ANOTHER B747 BELOW 2 OTHER ACFT. SINCE WE WERE WELL SHORT AND NOTHING WAS HAPPENING TO SECURE ACFT, I TOLD THE CREW I WOULD TRY TO TAXI FORWARD ON 1 ENG AND MADE AN ANNOUNCEMENT TO PAX TO HOLD ONTO A SEAT. PLACED THRUST TO APPROX 30 PERCENT N1 AND ACFT EASED FORWARD. AS WE APCHED THE ACTUAL B747 STOP BAR, I EASED ON SOME BRAKE WITH NO RESPONSE, SO I ADDED MORE BRAKE WITH NO RESPONSE, SO I PUT THE BRAKES TO THE FLOOR, AGAIN NO RESPONSE. I YELLED TO CREW, 'NO BRAKES -- GIVE ME PRESSURE.' SO RESPONDED WHILE I SWITCHED BRAKE SOURCE TO #2 WITH NO RESPONSE SO I CAPPED THE #2 BRAKE SWITCH AND ASKED SO TO SELECT SYS 1 AT THE SAME TIME FO REACHED OVER AND PULLED #1 INTO REVERSE THRUST. AT THIS POINT WE WERE SLOWING BUT HAD NO DIRECTIONAL GUIDANCE. AS PRESSURE CAME UP ON #1, ACFT STOPPED. NOTING FULL PRESSURE, I RESET BRAKES WAITING FOR GND SINCE WE WERE 18-24 INCHES FROM IMPACTING JETWAY WITH #2 ENG. GND MECH CALLED ON INTERPHONE INDICATING THEY WOULD PUSH US AWAY FROM FORWARD JETWAY THAT WAS AGAINST ACFT. PUSH WAS ACCOMPLISHED, BRAKES WERE SET, AND PAX DEPLANED. SUGGESTIONS: 1) ATTEMPT TO STANDARDIZE ACCU-PARK SYS TO AVOID CONFUSION. 2) B747 SOP COULD INCLUDE A STATEMENT TO LEAVE #2 AND #4 ADP'S ON UNTIL LAST ENG IS SHUT DOWN. 3) ACCU-PARK LIGHTS SHOULD BE TURNED OFF TO SIGNAL CREW, STOP TAXI. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR WAS CALLED TO INQUIRE AS TO WHAT HE MIGHT DO DIFFERENTLY THE NEXT TIME THIS SIT SHOULD OCCUR. RPTR STATED THAT HE WOULD MAKE CERTAIN THE AIR DRIVEN PUMPS WOULD NOT BE TURNED OFF UNTIL ALL ENGS HAD BEEN SHUT DOWN. THE CHKLIST FOR SHUTDOWN SAYS TO TURN OFF ALL HYD PUMPS WHEN ENGS ARE SHUT DOWN BUT COMMON PRACTICE IS TO SHUT DOWN HYD PUMPS WHEN EACH RESPECTIVE ENG IS SHUT DOWN AND NOT WAIT UNTIL ALL ENGS ARE SHUT DOWN. RPTR ALSO COUNTED ON AT LEAST 3 GOOD BRAKE APPLICATIONS FROM THE BRAKE HYD ACCUMULATOR, BUT THAT PRESSURE APPLICATION HAD ALREADY BEEN BLED OFF DURING THE STOPPING OF THE ACFT AT THE EARLY STOP POINT. RPTR HAS SEEN NO CHANGES IN PROCS COME FROM THE TRAINING DEPT SINCE THIS INCIDENT. NOR HAS ANY OTHER OFFICIAL SAID ANYTHING REGARDING THIS INCIDENT. RPTR DID SAY THE FO'S ACTIONS ARE WHAT STOPPED THE ACFT FROM FURTHER MOVEMENT FORWARD WHEN HE PUT THE #1 ENG IN REVERSE. DAMAGE TO THE ACFT WAS A 6-INCH DENT INTO THE FUSELAGE. SUPPLEMENTAL INFO FROM ACN 321699: WE DID NOT NOTICE THAT WE WERE SHORT OF OUR B747 GATE UNTIL AFTER SHUTTING #2, #3, AND #4 ENGS DOWN AND TURNING OFF SEAT BELT SIGN. CAPT TURNED SEAT BELT SIGN BACK ON AND MADE AN ANNOUNCEMENT. I BEGAN TO CALL OPS TO GET TOWED IN. CAPT PUSHED UP PWR AND WE MOVED FORWARD. THE CAPT TRIED TO STOP AND HIS BRAKES DID NOT WORK (SO HAD TURNED ALL HYD PUMPS OFF). I TRIED MY BRAKES AND THEY DID NOT WORK EITHER. THE CAPT AND SO WORKED ON THE HYD PROB AS WE CONTINUED FORWARD. I PUT THE #1 ENG INTO REVERSE TO STOP US. I THINK THAT IF YOU STOP AT GATE, YOU SHOULD GET TOWED FORWARD IF YOU HAVE TO MOVE AGAIN. SOMEONE UNDER THE ACFT COULD HAVE BEEN HURT. CALLBACK CONVERSATION WITH RPTR ACN 321699 REVEALED THE FOLLOWING INFO: RPTR WAS FLYING AS FO. HE ADDED THE FOLLOWING INFO TO THE NASA ASRS RPTS ALREADY FILED: THE CAPT AND SO JOINED HIMSELF AT A REQUIRED COMPANY CONFERENCE CALL TO DETERMINE WHAT MIGHT BE DONE DIFFERENTLY SO THIS TYPE OF INCIDENT WILL NOT HAPPEN AGAIN. RPTR WAS STRONGLY IN FAVOR OF NOT MOVING AN ACFT WHICH HAS STOPPED AND SHUT DOWN ENGS UNLESS A GND TUG DRIVER HOOKS UP AND MOVES THE ACFT. THE COMPANY INVOLVED SEEMED TO AGREE WITH HIM AND IS NOW WORKING TO MAKE THAT THE MANDATORY PROC. THE PREFERRED PROC WILL EVIDENTLY TAKE SOME TIME TO IMPLEMENT AS THE GND SVCS IN ENGLAND ARE SLOW TO COMPLY WITH ANY PROCS THAT ARE CHANGED. RPTR FEELS CONFIDENT THAT STANDARD PROC WILL BE TO MOVE ACFT ONLY BY GND TUG WHEN SMALL MOVEMENTS OF ACFT ARE NEEDED. RPTR ALSO STATED THAT HIS PUTTING #1 ENG INTO REVERSE IS WHAT STOPPED THE ACFT MOVEMENT.
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.