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|
Attributes | |
ACN | 518739 |
Time | |
Date | 200107 |
Day | Wed |
Local Time Of Day | 0601 To 1200 |
Place | |
Locale Reference | airport : anc.airport |
State Reference | AK |
Altitude | agl single value : 0 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | tower : anc.tower |
Operator | common carrier : air carrier |
Make Model Name | B747 Undifferentiated or Other Model |
Operating Under FAR Part | Part 121 |
Flight Phase | landing : roll |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Qualification | pilot : commercial pilot : cfi pilot : atp pilot : multi engine |
Experience | flight time last 90 days : 119 flight time total : 10375 flight time type : 5557 |
ASRS Report | 518739 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Qualification | pilot : flight engineer pilot : instrument pilot : multi engine pilot : atp pilot : cfi pilot : commercial |
Experience | flight time last 90 days : 155 flight time total : 8000 flight time type : 530 |
ASRS Report | 518146 |
Events | |
Anomaly | ground encounters other non adherence : published procedure non adherence : company policies other anomaly other |
Independent Detector | other other : mntnc personnel |
Resolutory Action | none taken : detected after the fact |
Consequence | other other |
Supplementary | |
Problem Areas | Flight Crew Human Performance |
Primary Problem | Flight Crew Human Performance |
Narrative:
The flight was scheduled to depart at XA45 on jul/xa/01, but departed ZZZ 43 mins late due to late loading. The flight was flown according to the flight plan except for several deviations for en route WX problems. In southern wisconsin the flight deviated around thunderstorms and in saskatchewan the flight climbed from FL350 to FL370 to escape turbulence in the cloud tops. About 30 mins later, the flight was cleared back down to FL350. Due to the significant delay departing ZZZ, mach .86 was flown in cruise to minimize the delay on arrival in anc. During cruise the captain set the speed book open to the estimated landing weight page of 550000 pounds. Since anc was VFR and clearly visible at top of descent, the flight maintained cruise altitude a little longer than usual to maintain cruise airspeed. Approximately 60 NM from yeska intersection a descent was initiated. Passing FL210 the captain called for the approach checklist. After the captain responded to the airspeed bugs call with the approach speeds for a 550000 pound landing, the flight engineer commented that the actual landing weight would be lower at approximately 532000 pounds. The captain stated to the first officer and flight engineer that the airspeed bug settings would be reduced 2 KTS each to comply with the approach speeds for the lighter landing weight. The first officer picked up the speed book and inadvertently flipped over several pages (instead of a single page) to the 445000 pound weight page for approach speeds. The captain immediately recognized a significant difference between the initial approach speeds and the speeds for the revised landing weight. As the captain was about to comment on the airspeed discrepancy, the airspeed overspd warning sounded at approximately 350 KTS. The captain promptly diverted his attention to smoothly and slowly raising the nose of the aircraft to reduce the airspeed. With the speed warning silenced, the captain set the new bug speeds from the speed book page and the remainder of the approach checklist was completed. Leveloff was completed at yeska intersection at 10000 ft and 250 KTS. Approach control gave the flight a 250 degree heading for a vector to final and descent to 8000 ft. Flaps were extended to further decrease the airspeed as the flight descended to 8000 ft and then down to 2000 ft. After passing a DC10 on final, the flight was cleared for a visual approach to runway 6R behind the DC10. The landing confign and checklist were completed at approximately 1500 ft MSL with medium automatic brakes selected. A smooth and stable final approach was flown at a bug speed of 135 KTS. During the approach the sun was shining very brightly just over the mountains ahead and the winds were calm. A normal flare was followed by a normal touchdown. After touchdown the nose attitude appeared higher than normal. The nose was slowly and smoothly lowered to touchdown and the aircraft exited the runway at taxiway G. After crossing runway 6L, the after landing checklist was completed and the flight proceeded to the anc ramp via taxiway right. The normal shutdown and secure checklists were completed in the chocks and the crew exited the aircraft. After the captain descended the boarding stairs, anc maintenance personnel commented that the aircraft had been involved in a tailstrike. Proceeding to the rear fuselage area, 4 spots were observed where paint had been rubbed off and a drain mast was bent to one side. The flight engineer confirmed that no damage was present during the preflight check. This incident occurred because the approach checklist was not followed precisely, ie, the speed bugs were not set for the correct aircraft landing weight. This incident probably could have been avoided if the captain had done 2 things differently. First, normally before top of descent, the captain would turn and observe the aircraft gross weight indication on the total fuel indicator on the flight engineer's panel. The estimated landing weight page of the speed book would then be adjusted as necessary for the proper estimated landing weight. In this situation the proper page was for a 535000 pound landing vice the 550000 pound weight which the captain had set at top of climb. Under normal circumstances the page remains the same, but occasionally the proper estimated landing weight is plus or minus 1 page (the pages are in 15000 pound increments which changes the approach speeds 2 KTS). If the captain had changed the speed book landing weight to the 535000 pound page, the speed bugs shouldhave been set properly. The second difference would be to fly a standard descent profile vice a high speed profile. A standard descent would have commenced about 90 NM from yeska intersection and maintained 320 KT airspeed to level off. This profile would have resulted in less wind noise, no airspeed overspd warning and more time to focus on ensuring that the correct landing weight page in the speed book was being used. Several other factors contributed to this incident. The excellent WX at top of descent prompted several of the 5 jump seat passenger to come forward to the cockpit to observe the beautiful scenery through the larger cockpit windows. Their presence and conversation distraction the captain from observing the aircraft gross weight on the total fuel indicator and adjusting the speed book landing weight page. Also, an ACARS message was received just before top of descent which directed the first officer to report for drug and alcohol test immediately after block in. This message prompted more conversation which diverted the captain's attention from his normal routine. The bright sunlight directly ahead on final during the visual approach caused the captain to not notice the higher pitch attitude as the aircraft was flown at a slower final approach speed. (The correct bug speed was 149 KTS -- the correct reference speed was 144 KTS. The speeds actually flown were 135 KTS and 130 KTS respectively -- 14 KTS less.) and lastly, fatigue probably diminished all 3 crew members normal alertness and attention to detail more than we realized. Each crew member had napped for a short period early in the flight. Towards the end of the flight we were all tired again and looking forward to arriving at the hotel for a good rest. To prevent this incident from ever being repeated, I will now modify my normal routine in 2 ways. First, a descent from cruise altitude will not be commenced until I have verified that the speed book is set for the proper estimated landing weight. Second, as the aircraft approachs 10000 ft MSL, I will turn to observe the aircraft gross weight on the total fuel indicator and confirm that the speed book is still set for the proper estimated landing weight. P.south. I believe that the tail strike occurred after landing when the ground spoilers deployed. The nose rose slightly at that time and I did not try to force it back down.
Original NASA ASRS Text
Title: A B747 CREW CAUSED A TAIL STRIKE UPON LNDG AT PANC.
Narrative: THE FLT WAS SCHEDULED TO DEPART AT XA45 ON JUL/XA/01, BUT DEPARTED ZZZ 43 MINS LATE DUE TO LATE LOADING. THE FLT WAS FLOWN ACCORDING TO THE FLT PLAN EXCEPT FOR SEVERAL DEVS FOR ENRTE WX PROBS. IN SOUTHERN WISCONSIN THE FLT DEVIATED AROUND TSTMS AND IN SASKATCHEWAN THE FLT CLBED FROM FL350 TO FL370 TO ESCAPE TURB IN THE CLOUD TOPS. ABOUT 30 MINS LATER, THE FLT WAS CLRED BACK DOWN TO FL350. DUE TO THE SIGNIFICANT DELAY DEPARTING ZZZ, MACH .86 WAS FLOWN IN CRUISE TO MINIMIZE THE DELAY ON ARR IN ANC. DURING CRUISE THE CAPT SET THE SPD BOOK OPEN TO THE ESTIMATED LNDG WT PAGE OF 550000 LBS. SINCE ANC WAS VFR AND CLRLY VISIBLE AT TOP OF DSCNT, THE FLT MAINTAINED CRUISE ALT A LITTLE LONGER THAN USUAL TO MAINTAIN CRUISE AIRSPD. APPROX 60 NM FROM YESKA INTXN A DSCNT WAS INITIATED. PASSING FL210 THE CAPT CALLED FOR THE APCH CHKLIST. AFTER THE CAPT RESPONDED TO THE AIRSPD BUGS CALL WITH THE APCH SPDS FOR A 550000 LB LNDG, THE FE COMMENTED THAT THE ACTUAL LNDG WT WOULD BE LOWER AT APPROX 532000 LBS. THE CAPT STATED TO THE FO AND FE THAT THE AIRSPD BUG SETTINGS WOULD BE REDUCED 2 KTS EACH TO COMPLY WITH THE APCH SPDS FOR THE LIGHTER LNDG WT. THE FO PICKED UP THE SPD BOOK AND INADVERTENTLY FLIPPED OVER SEVERAL PAGES (INSTEAD OF A SINGLE PAGE) TO THE 445000 LB WT PAGE FOR APCH SPDS. THE CAPT IMMEDIATELY RECOGNIZED A SIGNIFICANT DIFFERENCE BTWN THE INITIAL APCH SPDS AND THE SPDS FOR THE REVISED LNDG WT. AS THE CAPT WAS ABOUT TO COMMENT ON THE AIRSPD DISCREPANCY, THE AIRSPD OVERSPD WARNING SOUNDED AT APPROX 350 KTS. THE CAPT PROMPTLY DIVERTED HIS ATTN TO SMOOTHLY AND SLOWLY RAISING THE NOSE OF THE ACFT TO REDUCE THE AIRSPD. WITH THE SPD WARNING SILENCED, THE CAPT SET THE NEW BUG SPDS FROM THE SPD BOOK PAGE AND THE REMAINDER OF THE APCH CHKLIST WAS COMPLETED. LEVELOFF WAS COMPLETED AT YESKA INTXN AT 10000 FT AND 250 KTS. APCH CTL GAVE THE FLT A 250 DEG HDG FOR A VECTOR TO FINAL AND DSCNT TO 8000 FT. FLAPS WERE EXTENDED TO FURTHER DECREASE THE AIRSPD AS THE FLT DSNDED TO 8000 FT AND THEN DOWN TO 2000 FT. AFTER PASSING A DC10 ON FINAL, THE FLT WAS CLRED FOR A VISUAL APCH TO RWY 6R BEHIND THE DC10. THE LNDG CONFIGN AND CHKLIST WERE COMPLETED AT APPROX 1500 FT MSL WITH MEDIUM AUTO BRAKES SELECTED. A SMOOTH AND STABLE FINAL APCH WAS FLOWN AT A BUG SPD OF 135 KTS. DURING THE APCH THE SUN WAS SHINING VERY BRIGHTLY JUST OVER THE MOUNTAINS AHEAD AND THE WINDS WERE CALM. A NORMAL FLARE WAS FOLLOWED BY A NORMAL TOUCHDOWN. AFTER TOUCHDOWN THE NOSE ATTITUDE APPEARED HIGHER THAN NORMAL. THE NOSE WAS SLOWLY AND SMOOTHLY LOWERED TO TOUCHDOWN AND THE ACFT EXITED THE RWY AT TXWY G. AFTER XING RWY 6L, THE AFTER LNDG CHKLIST WAS COMPLETED AND THE FLT PROCEEDED TO THE ANC RAMP VIA TXWY R. THE NORMAL SHUTDOWN AND SECURE CHKLISTS WERE COMPLETED IN THE CHOCKS AND THE CREW EXITED THE ACFT. AFTER THE CAPT DSNDED THE BOARDING STAIRS, ANC MAINT PERSONNEL COMMENTED THAT THE ACFT HAD BEEN INVOLVED IN A TAILSTRIKE. PROCEEDING TO THE REAR FUSELAGE AREA, 4 SPOTS WERE OBSERVED WHERE PAINT HAD BEEN RUBBED OFF AND A DRAIN MAST WAS BENT TO ONE SIDE. THE FE CONFIRMED THAT NO DAMAGE WAS PRESENT DURING THE PREFLT CHK. THIS INCIDENT OCCURRED BECAUSE THE APCH CHKLIST WAS NOT FOLLOWED PRECISELY, IE, THE SPD BUGS WERE NOT SET FOR THE CORRECT ACFT LNDG WT. THIS INCIDENT PROBABLY COULD HAVE BEEN AVOIDED IF THE CAPT HAD DONE 2 THINGS DIFFERENTLY. FIRST, NORMALLY BEFORE TOP OF DSCNT, THE CAPT WOULD TURN AND OBSERVE THE ACFT GROSS WT INDICATION ON THE TOTAL FUEL INDICATOR ON THE FE'S PANEL. THE ESTIMATED LNDG WT PAGE OF THE SPD BOOK WOULD THEN BE ADJUSTED AS NECESSARY FOR THE PROPER ESTIMATED LNDG WT. IN THIS SIT THE PROPER PAGE WAS FOR A 535000 LB LNDG VICE THE 550000 LB WT WHICH THE CAPT HAD SET AT TOP OF CLB. UNDER NORMAL CIRCUMSTANCES THE PAGE REMAINS THE SAME, BUT OCCASIONALLY THE PROPER ESTIMATED LNDG WT IS PLUS OR MINUS 1 PAGE (THE PAGES ARE IN 15000 LB INCREMENTS WHICH CHANGES THE APCH SPDS 2 KTS). IF THE CAPT HAD CHANGED THE SPD BOOK LNDG WT TO THE 535000 LB PAGE, THE SPD BUGS SHOULDHAVE BEEN SET PROPERLY. THE SECOND DIFFERENCE WOULD BE TO FLY A STANDARD DSCNT PROFILE VICE A HIGH SPD PROFILE. A STANDARD DSCNT WOULD HAVE COMMENCED ABOUT 90 NM FROM YESKA INTXN AND MAINTAINED 320 KT AIRSPD TO LEVEL OFF. THIS PROFILE WOULD HAVE RESULTED IN LESS WIND NOISE, NO AIRSPD OVERSPD WARNING AND MORE TIME TO FOCUS ON ENSURING THAT THE CORRECT LNDG WT PAGE IN THE SPD BOOK WAS BEING USED. SEVERAL OTHER FACTORS CONTRIBUTED TO THIS INCIDENT. THE EXCELLENT WX AT TOP OF DSCNT PROMPTED SEVERAL OF THE 5 JUMP SEAT PAX TO COME FORWARD TO THE COCKPIT TO OBSERVE THE BEAUTIFUL SCENERY THROUGH THE LARGER COCKPIT WINDOWS. THEIR PRESENCE AND CONVERSATION DISTR THE CAPT FROM OBSERVING THE ACFT GROSS WT ON THE TOTAL FUEL INDICATOR AND ADJUSTING THE SPD BOOK LNDG WT PAGE. ALSO, AN ACARS MESSAGE WAS RECEIVED JUST BEFORE TOP OF DSCNT WHICH DIRECTED THE FO TO RPT FOR DRUG AND ALCOHOL TEST IMMEDIATELY AFTER BLOCK IN. THIS MESSAGE PROMPTED MORE CONVERSATION WHICH DIVERTED THE CAPT'S ATTN FROM HIS NORMAL ROUTINE. THE BRIGHT SUNLIGHT DIRECTLY AHEAD ON FINAL DURING THE VISUAL APCH CAUSED THE CAPT TO NOT NOTICE THE HIGHER PITCH ATTITUDE AS THE ACFT WAS FLOWN AT A SLOWER FINAL APCH SPD. (THE CORRECT BUG SPD WAS 149 KTS -- THE CORRECT REF SPD WAS 144 KTS. THE SPDS ACTUALLY FLOWN WERE 135 KTS AND 130 KTS RESPECTIVELY -- 14 KTS LESS.) AND LASTLY, FATIGUE PROBABLY DIMINISHED ALL 3 CREW MEMBERS NORMAL ALERTNESS AND ATTN TO DETAIL MORE THAN WE REALIZED. EACH CREW MEMBER HAD NAPPED FOR A SHORT PERIOD EARLY IN THE FLT. TOWARDS THE END OF THE FLT WE WERE ALL TIRED AGAIN AND LOOKING FORWARD TO ARRIVING AT THE HOTEL FOR A GOOD REST. TO PREVENT THIS INCIDENT FROM EVER BEING REPEATED, I WILL NOW MODIFY MY NORMAL ROUTINE IN 2 WAYS. FIRST, A DSCNT FROM CRUISE ALT WILL NOT BE COMMENCED UNTIL I HAVE VERIFIED THAT THE SPD BOOK IS SET FOR THE PROPER ESTIMATED LNDG WT. SECOND, AS THE ACFT APCHS 10000 FT MSL, I WILL TURN TO OBSERVE THE ACFT GROSS WT ON THE TOTAL FUEL INDICATOR AND CONFIRM THAT THE SPD BOOK IS STILL SET FOR THE PROPER ESTIMATED LNDG WT. P.S. I BELIEVE THAT THE TAIL STRIKE OCCURRED AFTER LNDG WHEN THE GND SPOILERS DEPLOYED. THE NOSE ROSE SLIGHTLY AT THAT TIME AND I DID NOT TRY TO FORCE IT BACK DOWN.
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.