FDAI logo   ::  Site Map  ::   
Home  |  About This Website  |  Contact Us
About This Website » ASRS Incident Report Analysis » Incidents related to Issue

Incidents related to Issue 6 incidents related to this issue.

Issue: manual operation may be difficult after transition from automated control (Issue #55)
Description: In some situations flight control may be difficult after transition from automated to manual flight.

  1.  
  2. Accession Number: 371142
    Synopsis: MLG FLC IN DSCNT HAS AUTOPLT TRIM PROB AND IS UNABLE TO MAINTAIN ALT. WHEN DISCONNECTING AUTOPLT THEY DSND ABOUT 250 FT.
    Narrative: WHILE IN DSCNT TO 16000 FT MSL ON AUTOPLT, LEVELING AT 16000 FT MSL AND SLOWING TO 250 KIAS IN AIRSPD, AUTOPLT WAS UNABLE TO TRIM AND MAINTAIN 16000 FT MSL. AS A RESULT, THE FO DISCONNECTED THE AUTOPLT (WHICH GAVE A BUMP DUE TO OUT-OF-TRIM) AND DSNDED ABOUT 250 FT BELOW 16000 FT MSL IN AN EFFORT TO MAINTAIN PAX COMFORT. WE CORRECTED BACK TO 16000 FT MSL IMMEDIATELY, AND HAD NO FURTHER PROBS.

  3.  
  4. Accession Number: 383607
    Synopsis: FLC OF MD83 MAKING A CAT II LNDG HAS LOSS OF ACFT CTL DUE TO RWY COVERED WITH SNOW AND ICE. BRAKING RPTED AS FAIR BUT ACTUALLY NIL.
    Narrative: I WAS FLYING AS FO IN AN MD80. THE FLT WAS FROM SEA TO ANC. WX IN ANC WAS 600 FT OVCST, 1/4 MI VISIBILITY WITH BLOWING SNOW AND MIST. THE WIND WAS 330 DEGS AT 14 KTS, AND WE WERE LNDG RWY 6R. RWY 6R WAS COVERED WITH SNOW AND ICE WITH BRAKING ACTION RPTED AS FAIR. BECAUSE OF THE LOW WX MINIMA, AND THE FACT THAT THE CAPT WAS RESTR TO A CAT II LNDG (DUE TO BEING A NEW CAPT), WE FLEW A CAT II AUTOLAND APCH. THE APCH WAS NORMAL AND THE AUTOLNDG WAS NORMAL. UPON ROLLOUT THE ACFT DEVIATED (1/4 DOT RMI) FROM THE CTRLINE (ALSO NORMAL), AND INITIATED A CORRECTION N. THE CORRECTION WAS CORRECT AND WITHIN NORMAL LIMITS, BUT THE ACFT BEGAN TO SLIDE TOWARD THE N SIDE OF THE RWY. THE CAPT DISCONNECTED THE AUTOPLT AND TOOK OVER MANUALLY. BRAKING AND STEERING WERE INEFFECTIVE, SO THE ACFT WAS BROUGHT TO A STOP AND DIRECTIONAL CTL MAINTAINED USING DIFFERENTIAL REVERSE THRUST. THE ACFT RAN OVER AND DESTROYED 5 RWY EDGE LIGHTS. THE ACFT WAS INSPECTED ON THE TXWY BY MAINT AND NO DAMAGE WAS FOUND. CONTRIBUTING FACTORS WERE BALD, BUT WITHIN LIMITS OF WEAR, MAIN TIRES. A 14 KT XWIND AND A RWY BRAKING CONDITION OF NIL, BUT RPTED AS FAIR. ADDITIONAL FACTORS MAY BE ATTRIBUTED TO THE FEDERAL REQUIREMENT THAT THE LOW TIME CAPT MAKE A CAT II AUTOLAND. THE CAT II AUTOLAND RESTRICTS THE PLT FROM DEVELOPING A FEEL FOR THE ACFT UNTIL AFTER LNDG. A CAT II LNDG FROM AN ILS, THAT IS, NOT AN AUTOLNDG, MIGHT HAVE PREVENTED THE RWY DEV.

  5.  
  6. Accession Number: 395563
    Synopsis: A320 ACFT ARRIVING FOR APCH HAD DUAL FMGC TIMEOUTS WHICH CAUSED LOSS OF AUTOPLTS, AUTOTHRUST, FLT DIRECTORS AND NAV DISPLAYS. PNF, CAPT BECAME DISTR IN RESETTING THE FMGC'S AND FLC LANDED WITHOUT TWR CLRNC.
    Narrative: FLYING DIRECT TO FAF IN A320 ACFT, BOTH FMGC'S TIMED OUT CAUSING LOSS OF AUTOPLTS, AUTOTHRUST, FLT DIRECTORS, AND ALL NAV DISPLAY. NOTIFIED ATC OF LOSS AND RECEIVED VECTORS FOR VISUAL APCH. I WAS PF AND AM NEW IN THIS TYPE ACFT, SO ALL THE LOSSES OF DATA AND AIDS FORCED ME TO CONCENTRATE HEAVILY ON FLYING ACFT MANUALLY. CAPT HANDLED RADIOS AND WORKED ON GETTING FMGC'S BACK ON LINE. PROCEEDED TO LAND NORMALLY WITHOUT A CHANGE IN ACFT STATUS. UPON TAXIING CLR OF RWY, I CALLED TWR TO SAY WE WERE CLR, BUT RADIO WAS STILL TUNED TO APCH. I SUSPECT WE LANDED WITHOUT TALKING TO TWR OR GETTING CLRNC. WHEN WE CALLED GND CTL NO ONE SAID ANYTHING TO US, AND WE DID NOT PUSH THE ISSUE. APPARENTLY CAPT WAS ENGROSSED WITH MALFUNCTION AND FAILED TO CALL TWR PRIOR TO LNDG, AND WITH MY EXTRA CONCENTRATION ON FLYING MANUALLY, I FAILED TO CATCH IT. I THINK CHKLISTS FOR EVEN NORMAL OPS SHOULD HAVE 'LNDG CLRNC RECEIVED' AS PART OF THE LNDG/FINAL CHKLIST. I AM NOT AWARE OF ANY AIRLINES DOING THIS NOW.

  7.  
  8. Accession Number: 400455
    Synopsis: CL65 ACFT IN CRUISE HAD CAUTION MESSAGE THAT AIRSPD AND ALT READOUTS WERE UNRELIABLE. AS PLT'S AIRSPD READOUT INCREASED, RPTR CAPT COMMENCED A CLB TO PREVENT AN OVERSPD. WHEN DSNDING BACK TO ALT TCASII GAVE AN RA ON ACFT 1000 FT BELOW AND APPROX 5 MILES. SEPARATION WAS LOST DUE TO ALT DEVIATION.
    Narrative: IN CRUISE AT FL310 AT MACH .80 EFIS COMPARATOR MONITOR CAUTION MESSAGE APPEARED, FOLLOWED BY MACH TRIM CAUTION. THIS CAUSED THE PRIMARY AIRSPD AND ALT READOUTS TO FLAG AND BECOME UNRELIABLE. PLT'S AIRSPD READOUT BEGAN TO INCREASE AND OVERSPD WARNING SOUNDED CONTINUOUSLY. THE ALT READOUTS VARIED AND THEN DISAPPEARED FROM VIEW. AIR TRAFFIC CTL WAS INFORMED THAT WE HAD LOST SOME OF OUR PRIMARY INSTRUMENTS AND DUE TO THE OVERSPD POSSIBILITY OUR ALT MAY VARY. INITIALLY A CLB WAS MADE AND PWR REDUCED TO ENSURE THE ACFT WAS NOT BEING OVERSPED. TRANSITION WAS MADE TO THE STANDBY INSTRUMENTS AND A DSCNT INITIATED TO RETURN TO FL310. AS WE NEARED FL310 ON THE STANDBY INSTRUMENTS, TCASII TRAFFIC MESSAGE SOUNDED FOLLOWED BY AN RA COMMANDING A CLB. THE CLB WAS BEGUN TO COMPLY WITH THE TCASII RA. WE OBSERVED A TARGET AT 1000 FT BELOW OUR ALT AT FIVE MI RANGE ON THE TCASII SCREEN. ZAU GAVE US A PHONE NUMBER TO CALL AND INFORMED US THAT MINIMUM SEPARATION HAD BEEN VIOLATED. DURING THIS TIME THE QUICK REFERENCE HANDBOOK WAS CONSULTED AND CHECKLIST PROCS TO REGAIN INSTRUMENTS BEGUN. IT WAS DETERMINED THAT AN AIR DATA COMPUTER HAD FAILED. AFTER SELECTING THE ALTERNATE AIR DATA COMPUTER THE AIRSPD AND ALT TAPES REAPPEARED BUT THE OVERSPD CLACKER CONTINUED TO SOUND SO WE CONSIDERED THE PRIMARY INSTRUMENTS UNRELIABLE AND CONTINUED ON STANDBY INSTRUMENTS. WE WERE GIVEN A DSCNT AND MADE AN UNEVENTFUL LNDG IN ATW. A MAINT WRITE-UP WAS ENTERED IN THE LOGBOOK AND THE SYS INSPECTED IN ATW. NO DEFECTS WERE FOUND IN CHECKING THE AIR DATA SYSTEM AND THE ACFT WAS FLOWN BACK TO CVG AND CONTINUED IN SERVICE. THIS ACFT HAS A HIGHLY AUTOMATED COCKPIT AND IT IS VERY USER FRIENDLY AS LONG AS THE AUTOMATION WORKS. IT WAS VERY DIFFICULT TO TRANSITION TO THE STANDBY INSTRUMENTS BECAUSE OF THEIR SIZE, AND THE SPD OF THE ACFT AT THE MOMENT OF THE MALFUNCTION MADE IT NECESSARY TO FLY VERY CAREFULLY TO AVOID LARGE DEVIATIONS IN AIRSPD OR ALT. THE SMALL SIZE OF THE ATTITUDE INDICATORS ALSO CONTRIBUTES TO THE DIFFICULTY OF MAINTAINING AIRSPD AND ALT. IF ANYTHING THIS INCIDENT POINTED OUT TO ME THE NECESSITY TO TRAIN WITH THE AUTOMATION REMOVED SO IF THE ELECTRONICS FAIL THE AIRCREW CAN CONTINUE THE FLT WITHOUT SERIOUS CONSEQUENCES. A CONTRIBUTING FACTOR TO THE LOSS OF SEPARATION WAS THE FACT THAT THE PRIMARY INSTRUMENTS HAVE A MACH TRANSDUCER TO COMPENSATE FOR ERROR IN ALT AND AIRSPD BUT THE STANDBY INSTRUMENTS DO NOT. THE STANDBY ALTIMETER ALWAYS VARIES FROM THE PRIMARY BY AT LEAST 400 -500 FT AND SOMETIMES MORE AT HIGH ALT. BY FOLLOWING THE STANDBY ALTIMETER WE WERE ALMOST CERTAINLY GOING TO BE AT AN ALT THAT WOULD RESULT IN REDUCED SEPARATION.

  9.  
  10. Accession Number: 409730
    Synopsis: ACR MD88 FLC EXPERIENCED AN AC ELECTRICAL BUS FAILURE ON DEP, DRIFTING OFF COURSE UNTIL SYS FAILURE COULD BE OVERCOME. FLT RETURNED TO LAND WITHOUT FURTHER DIFFICULTY.
    Narrative: DURING CLB, LOST L AC ELECTRICAL BUS BAR, THUS AUTOPLT, AUTOTHROTTLES AND COURSE GUIDANCE DISAPPEARED. TOOK A WHILE TO FIND ANOTHER WAY TO MONITOR COURSE. DURING THIS TIME, THE SID COURSE HAD CHANGED AND AS A RESULT, WE WERE OFF COURSE, PROBABLY A COUPLE OF MI. THERE WAS NO LOSS OF SEPARATION. IT JUST TOOK A WHILE AFTER LOSING FMS AND MAP TO FIGURE OUT HOW TO USE CDI WITHOUT COURSE SELECT WINDOW WORKING. SUPPLEMENTAL INFO FROM ACN 410003: ZFW QUERIED US STATING HE SHOWED US ABOUT 4 MI N OF COURSE. AN APPARENT EQUIP PROB WITH OUR ACFT FMS. DEAD RECKONING MESSAGES STARTED TO APPEAR. MAP DISPLAYS WERE SHIFTED NOTICEABLY TO THE L. FMS VOR AND DME UPDATING FUNCTIONS WERE NOT OPERATING PROPERLY. UPDATED POS OVER KNOWN POINT AND ALL MALFUNCTIONS RETURNED TO NORMAL.

  11.  
  12. Accession Number: 410070
    Synopsis: FLC OF A B757 OVERSHOT ASSIGNED ALT DURING A STAR ARR DUE TO THE ACFT'S OVERSPD WARNING DISTR AND IMMEDIATELY STARTED RETURN WHEN ATC CLRED THEM TO A LOWER ALT. THE FO WAS MANUALLY FLYING ACFT DUE TO THE ALT BUG OF THE MODE CTL PANEL BECOMING INOP.
    Narrative: DURING OUR INITIAL DSCNT INTO MSP WE WERE CLRED TO DSND FROM AN INTERMEDIATE ALT TO FL240. DURING THIS INTERMEDIATE PERIOD OUR ALT CTL BUG ON THE MODE CTL PANEL (MCP) FAILED TO OPERATE AT ABOUT FL246 AND STUCK IN THIS POS FOR THE REST OF THE FLT. THE FO WAS FLYING THE ACFT AND I (THE CAPT) INSTRUCTED HIM TO FLY THE ACFT MANUALLY, SINCE ALL LEVELOFF LOGIC WAS BASED ON THE MCP ALT WINDOW. WE WERE KEPT HIGH ON THE ARR BECAUSE OF TFC AND THEN WERE CLRED TO CROSS GOLLF INTXN AT 11000 FT. THE FO DSNDED MANUALLY, DEPLOYING THE SPD BRAKES AND INCREASING AIRSPD TO 340 KTS IN ORDER TO MAKE THE RESTR. I THEN STARTED TO TROUBLESHOOT THE PROB WITH HOPES OF RESTORING THE MCP AND RETURNING TO AUTOMATIC FLT WHILE THE FO CONTINUED TO FLY THE ACFT. AS WE APCHED 11000 FT, THE OVERSPD WARNING SOUNDED ON THE ACFT AND DISTRACTED US JUST LONG ENOUGH TO DIP BELOW THE 11000 FT RESTR. WE LEVELED AT 10400 FT AND STARTED AN IMMEDIATE CLB BACK TO 11000 FT. AS WE STARTED OUR CLB BACK TO 11000 FT WE WERE ALMOST IMMEDIATELY GIVEN THE CLRNC TO DSND TO 10000 FT. WE DSNDED TO 10000 FT AND FLEW THE REST OF THE FLT MANUALLY WITH A NORMAL LNDG AT MSP. THE ALT BUST WAS THE RESULT OF 4 FACTORS WORKING IN CONCERT: 1) MECHANICAL FAILURE OF THE MCP ALT BUG. 2) THE SUDDEN REQUIREMENT TO FLY THE ACFT MANUALLY (VERY RARE SIT ON THE B757) WITH NO FLT GUIDANCE. 3) THE AGGRESSIVE DSCNT RATE REQUIRED TO MAKE THE STAR ALT REQUIREMENT. 4) THE LAST MIN DISTR OF THE ACFT OVERSPD WARNING WHILE APCHING LEVELOFF ALT.
Flight Deck Automation Issues Website  
© 1997-2013 Research Integrations, Inc.