What happened
The FAA’s narrative, in sentence case. The FAA writes it in capitals and removes private details.
(.4)During arrival, the flight (flt) received vectors for ILS runway (rwy) 4R approach (apch). Before reaching final apch fix, visibility went below minimums for rwy 4R, & flt was offered ILS rwy 4L apch, which was still above minimums. Captain accepted, & 1st officer (f/o), who was flying the aircraft (acft), transitioned to 4L. On final apch, acft passed thru 500' AGL at 151 KCAS with throttles near idle. It continued decelerating to reference landing speed. During computer-driven, auto-land flare, acft nose rotated up, & acft's tail struck rwy. The operator's (oper's) procedures required mandatory go-around unless apch was stabilized at 500'. The crew reported all checklists had been completed; however, apch charts for rwy 4L were not reviewed, required call outs were not remembered as given by all crewmembers, & altimeter bugs remained set for runway 4R. Dfdr data revealed the wing leading edge slats had not extended with the flaps. A green light on the pilot's instrument panel & 14 green lights & a gauge on the flt engineer's (f/e's) panel were not used to verify slat extension. Oper's expanded landing checklist did not require f/e to use gauge to verify slat extension. Oper's manuals did not list possibility of a 'slat lock', which would not activate any warning lights or aural warnings. Maintenance records revealed slats had locked 12 times in preceding 2 yrs. Inspection methods provided by Lockheed & adopted by the oper, did not adequately specify how to check slat drive system for slack.
As the FAA filed it
(.4)DURING ARRIVAL, THE FLIGHT (FLT) RECEIVED VECTORS FOR ILS RUNWAY (RWY) 4R APPROACH (APCH). BEFORE REACHING FINAL APCH FIX, VISIBILITY WENT BELOW MINIMUMS FOR RWY 4R, & FLT WAS OFFERED ILS RWY 4L APCH, WHICH WAS STILL ABOVE MINIMUMS. CAPTAIN ACCEPTED, & 1ST OFFICER (F/O), WHO WAS FLYING THE AIRCRAFT (ACFT), TRANSITIONED TO 4L. ON FINAL APCH, ACFT PASSED THRU 500' AGL AT 151 KCAS WITH THROTTLES NEAR IDLE. IT CONTINUED DECELERATING TO REFERENCE LANDING SPEED. DURING COMPUTER-DRIVEN, AUTO-LAND FLARE, ACFT NOSE ROTATED UP, & ACFT'S TAIL STRUCK RWY. THE OPERATOR'S (OPER'S) PROCEDURES REQUIRED MANDATORY GO-AROUND UNLESS APCH WAS STABILIZED AT 500'. THE CREW REPORTED ALL CHECKLISTS HAD BEEN COMPLETED; HOWEVER, APCH CHARTS FOR RWY 4L WERE NOT REVIEWED, REQUIRED CALL OUTS WERE NOT REMEMBERED AS GIVEN BY ALL CREWMEMBERS, & ALTIMETER BUGS REMAINED SET FOR RUNWAY 4R. DFDR DATA REVEALED THE WING LEADING EDGE SLATS HAD NOT EXTENDED WITH THE FLAPS. A GREEN LIGHT ON THE PILOT'S INSTRUMENT PANEL & 14 GREEN LIGHTS & A GAUGE ON THE FLT ENGINEER'S (F/E'S) PANEL WERE NOT USED TO VERIFY SLAT EXTENSION. OPER'S EXPANDED LANDING CHECKLIST DID NOT REQUIRE F/E TO USE GAUGE TO VERIFY SLAT EXTENSION. OPER'S MANUALS DID NOT LIST POSSIBILITY OF A 'SLAT LOCK', WHICH WOULD NOT ACTIVATE ANY WARNING LIGHTS OR AURAL WARNINGS. MAINTENANCE RECORDS REVEALED SLATS HAD LOCKED 12 TIMES IN PRECEDING 2 YRS. INSPECTION METHODS PROVIDED BY LOCKHEED & ADOPTED BY THE OPER, DID NOT ADEQUATELY SPECIFY HOW TO CHECK SLAT DRIVE SYSTEM FOR SLACK.
NTSB investigation
The NTSB’s investigation of this event, with its probable cause and findings. Matched to this report by N-number and date.
Other reports on N31031 · 3
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