FMC OF AN LGT ACR ACFT MALFUNCTIONED DURING A 'COUPLED' APCH RESULTING IN THE ACFT APCHING A STALL AND GAR.

Narrative

DURING COUPLED APCH (AUTOPLT AND THROTTLES) IN LNDG CONFIGN AT APPROX 1800 FT; AUTOPLT PITCHED UP WITHOUT THROTTLES; AIRSPD IMMEDIATELY DECAYED TO STICK SHAKER. FULL PWR WAS APPLIED AND RECOVERY COMPLETED WITH SEVERAL ALT CHANGES. ALL FMC INFO HAD BEEN LOST. SECOND APCH HAD NO GEAR LIGHT. THIRD APCH AND LNDG WAS NORMAL. DO NOT KNOW THE CAUSE; ACFT CHKED FOR LIGHTNING STRIKE. NO EVIDENCE FOUND. CALLBACK CONVERSATION WITH REPORTER REVEALED THE FOLLOWING: RPTR STATED THAT EVERYTHING WAS NORMAL DURING AN AUTO COUPLED APCH UNTIL HE; THE CAPT; NOTICED THAT THE AIRSPD WAS DECAYING FASTER THAN EXPECTED TO THE 'VRF BUG' WHILE THE FO WAS FLYING. THEN; THE ACFT PITCHED UP WITHOUT ANY ADVANCEMENT OF THE PWR LEVERS AND THE AIRSPD FURTHER DECAYED TO APPROX 80-90 KTS AT WHICH TIME THE ACFT 'STICK SHAKER' CAME ON INDICATING THE APCH OF A STALL. AT THE SAME TIME; THE 2 FLT SCREENS ON BOTH SIDES OF THE COCKPIT WENT BLANK LEAVING NO HDG OR NAVIGATING INFO AVAILABLE. THE CAPT IMMEDIATELY ADVANCED FULL PWR AND CLBED; SINCE THE PITCH TRIM SEEMED ALL THE WAY NOSE HIGH (IT IS NOTED THAT THE ACFT AUTOMATICALLY TRIM NOSE HIGH FOR THE LNDG FLARE OUT WHEN AUTO COUPLED). THE CAPT HAD SUCH A DIFFICULT TIME OVERRIDING THE PITCH UP ATTITUDE THAT THE STICK SHAKER STAYED ON FOR A FEW MOMENTS DURING THE CLB AND THE ACFT WAS FINALLY LEVELED AT 7000 FT. AT NO TIME DID THE ACFT GO BELOW APCH ALT LIMITS. THE CABIN ATTENDANTS WERE ADVISED OF A WIND SHEAR PROB FOR THE GAR. DURING THE SECOND APCH; THE R MAIN LNDG DOWN LIGHTS WERE NOT LIGHTED; THEREFORE; THIS APCH WAS ABANDONED FOR TRYING TO CORRECT THIS PROB. IT WAS FOUND THAT BOTH R MAIN GEAR LIGHT BULBS WERE BURNED OUT AND ONLY ONE WAS FOUND FOR REPLACEMENT WHICH SHOWED THE GEAR DOWN. THE THIRD AND LAST APCH WAS NORMAL. HOWEVER; EMER EQUIP WAS STANDING BY TOGETHER WITH COMPANY MAINT PERSONNEL. THE CAPT FURTHER STATED THAT MAINT COULD NOT FIND THE REAL PROB BUT DID RESTRICT THE USE OF THE AUTO THROTTLES ON THE NEXT FLT. THEY DID NOT REVIEW THE ACFT FLT DATA RECORDERS SINCE THEY THOUGHT ABOUT IT AFTER THE TIME THAT IT WAS AVAILABLE AND WAS RECORDED OVER! HE BELIEVED THAT THE FAILURE ACTED LIKE IT WAS CAUSED BY A LIGHTNING STRIKE; HOWEVER; HE DOES NOT THINK THAT ANY OCCURRED BECAUSE OF THE LACK OF THAT TYPE OF WX. HE STATED THAT WHEN THIS HAPPENED; HE BELIEVED THAT IT WAS HIS LAST FLT AS HE DID NOT THINK THE ACFT WOULD RECOVER. HE FURTHER STATED THAT THIS WAS HIS FIRST SOLO FLT IN THIS TYPE OF ACFT AND WAS THEREFORE NOT AS FAMILIAR WITH THE POSSIBLE PROBS OF CORRECTIVE ACTIONS. HOWEVER; HE SAID THAT THERE WAS NO TIME TO EVEN LOOK AT ANY VITAL ACFT READOUTS OR MAKE ADJUSTMENT OTHER THAN ATTEMPT TO RETRIM AND CTL THE ACFT. WHEN ASKED ABOUT THE REACTION OF THE OTHER CREW MEMBERS AND PAX; HE RESPONDED THAT HE HEARD NOTHING FROM THE PAX AND ONLY CONFIRMATION THAT THERE WAS A WIND SHEAR PROB BY THE FLT ATTENDANTS AND THAT THEY SEEMED CONTENT WITH THE COMPLETION OF THE FLT. THERE WERE NO INJURIES AND NO SUBSEQUENT FEEDBACK. HE WAS ALSO ASKED IF HE HEARD OF ANY OTHER SIMILAR INSTANCES AND HE HAD NOT. HOWEVER; HE KNOWS THAT HIS COMPANY AND THE MANUFACTURER WERE STUDYING THE PROB.