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Incidents related to Issue 15 incidents related to this issue.

Issue: false alarms may be frequent (Issue #70)
Description: Frequent false alarms may cause pilots to mistrust or ignore automation and therefore not use it or respond to it when they should.

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  2. Accession Number: 88059
    Synopsis: COMPANY BULLETIN REFERENCE POSSIBLE REASONS FOR MISSED RADIO CALLS IN MLG ACFT.
    Narrative: COMPLAINTS FROM SEVERAL ATC FACS HAVE IDENTIFIED THAT MLG CREWS ARE MISSING A HIGH NUMBER OF RADIO CALLS DURING THE DSNT AND APCH PHASES OF FLT. A RECENT "WINDY CITY NEWSLETTER" ALLUDED TO THIS FACT. INFORMAL POLLING OF MLG CREWS HAS LED TO THE FOLLOWING DISCUSSION AND CONCLUSION. THE INCREASED WORKLOAD BECAUSE OF THE 2-M CREW DOES NOT SEEM TO BE THE MAIN CONTRIBUTING FACTOR. OFTER WHEN 1 PLT ATTEMPTS TO DO TOO MUCH THE WORK FLOW IS DISRUPTED TO THE POINT WHERE NEITHER IS SURE WHAT HAS BEEN ACCOMPLISHED. A PLT DOING THIS, THOUGH MOTIVATED BY THE DESIRE TO DO A BETTER JOB, USUALLY CAUSES THE OTHER PLT TO EITHER LOWER HIS AWARENESS OR JUST TAKE HIMSELF OUT OF THE LOOP. MISSED CALLS! THE LOW RELATIVE COCKPIT EXPERIENCE ON THE MLG COULD ALSO BE A FACTOR IN MISSING ATC CALLS EXCEPT THAT THE PROB SEEMS TO BE EQUALLY DISTRIBUTED AMONG JUNIOR AND SENIOR CREWS. THIS IS NOT TO SAY THAT A NEW CREW MEMBER IN EITHER SEAT DOES NOT CREATE A HEAVIER WORKLOAD ON THE OTHER PLT. THE PARTICULARS OF THE MLG AUTOPLT FLT DIRECTOR SYS ALLOWS SO MANY OPTIONS, ESPECIALLY IN DSNT, THAT THE OVERSIGHT RESPONSIBILITIES ARE GREATLY INCREASED WHILE A PLT NEW TO THE EQUIP GETS COMFORTABLE WITH HIS TECHNIQUE. WHILE INCREASING WORKLOAD THIS SITUATION NORMALLY LEADS TO A HIGHER LEVEL OF VIGILANCE AND GREATER OPERATING MARGINS. IF THESE WERE PRIMARY CAUSES OF THE MISSED RADIO CALLS OTHER ACR'S MLG, ALSO JUNIOR EQUIP, AND EVEN OUR WDB WOULD SHARE IN THE GRIEF FELT BY ATC. DISTR SEEMS TO BE THE PRIMARY REASON FOR MISSED RADIO CALLS ON THE MLG. THIS DISTR, MOST AGREE, IS CAUSED BY CAWS OR MORE AFFECTIONATELY, "EDITH." VOICE WARNINGS ARE PERSISTENT AND OFTEN OCCUR DURING THE MOST NORMAL SITUATIONS. THROTTLES RETARDED AND AIRSPD 210 KTS OR BELOW IT SCREAMS "LNDG GEAR." SET THE MISSED APCH ALT, CONCENTRATE ON FLYING A CLOSE APCH AND "ALT" YELLS TWICE. THE MOST COMMON STATEMENT IN AN MLG COCKPIT DURING DSNT AND APCH IS PROBABLY, "SHUT IT UP." A NEW COROLLARY TO MURPHY'S LAW IS: CAWS WILL SCREAM WHEN ATC IS CALLING! CAWS IS NOT GOING TO DISAPPEAR IN THE IMMEDIATE FUTURE. THE PERFECT WORLD WOULD ALLOW THOSE WHO MUST DEAL WITH A SYS TO BE THE FINAL EVALUATORS AS TO ITS NECESSITY. HOWEVER, THE DESIGN ENGRS SEEM TO HAVE THE ABILITY TO SELL THE FAA A SYS W/O THE INPUT FROM THOSE WHO WILL USE IT. AT THE VERY LEAST, "LNDG GEAR" SHOULD BE ASSOCIATED WITH THE RADIO ALTIMETER, NOT AIRSPD. WE CAN LAND AT ANY SPD THOUGH NEVER W/O SOMETHING TO LAND ON! HOPEFULLY, ALL VOICE WARNINGS WILL BE REEVALUATED. MANY ACFT HAVE SUCCESSFULLY COMPLETED THOUSANDS OF CYCLES W/O CAWS TECHNOLOGY. MISSED CALLS ARE A REAL PROB ON THE MLG. BE AWARE OF IT. OFTEN JUST KNOWING A PROB EXISTS IS A REAL STEP TOWARD SOLVING IT. REMEMBER, WHEN YOU HEAR "LNDG GEAR," ATC IS TRYING TO REACH YOU! WE HAVE TO LIVE WITH THE DISTRS OF CAWS, TRY TO MINIMIZE THEIR EFFECTS. AS CHIEF ALWAYS SAYS, "BE CAREFUL OUT THERE." I MIGHT ADD, "THE NEXT $10000 COULD BY YOURS!"

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  4. Accession Number: 122251
    Synopsis: FO FLYING HVT AT FL390 MAKING A TURN WITH TURN KNOB ON AUTOPLT, ACFT LOST ALT AND ATTITUDE GYRO TUMBLED.
    Narrative: THE EVENT OCCURRED WHILE MAKING A TURN WITH THE AUTOPLT TURN KNOB THROUGH ABOUT 40-50 DEG USING 10-12 DEGS ANGLE OF BANK. DURING THIS TURN I WAS DISTRACTED FOR A FEW SECONDS BY "WAYPOINT PAPERWORK". THE AUTOPLT FAILED TO HOLD ALT AND WHILE REMAINING ENGAGED, BEGAN A 500-800 FPM DSNT. THE DSNT WAS NOTICED AT ABOUT 300' BELOW ASSIGNED ALT, HOWEVER, SPEED HAD ALREADY BUILT UP TO M .83 OR M .84. AT THE MOMENT THAT I REACHED FOR THE CONTROLS TO RECOVER, MY ATTITUDE GYRO TUMBLED LEAVING ME WITH NO PITCH REFERENCE. HIGH SPEED MACH BUFFET WAS EXPERIENCED AND THE CAPT RECOVERED FROM THE DSNT WITH A TOTAL ALT LOSS OF 1000'. NO TFC CONFLICT FROM THE DSNT WAS NOTED. SEVERAL FACTORS WERE CONTRIBUTING: 1) THERE HAD BEEN SEVERAL PREVIOUS WRITEUPS OF AUTOPLT PITCH MALFUNCTIONS. HOWEVER, THE AUTOPLT HAD BEEN MEL'ED WITH PITCH TRIM INOP. ON ALL PREVIOUS SEGMENTS OF THIS TRIP (16 HRS), WHEN THE PITCH TRIM FAILED, THE AUTOPLT DISCONNECTED WITH THE ASSOCIATED AURAL AND VISUAL WARNING -- MUCH LESS OF A PROBLEM THAN DIVING WITH NO WARNING. WITH THE PITCH TRIM INOP, THE AUTOPLT SHOULD NOT HAVE BEEN USED AT ALL. 2) THE F/O'S ATTITUDE GYRO HAD BEEN TUMBLING ON PREVIOUS SEGMENTS. THE MECHANIC SWAPPED GYRO'S BUT THE CAPT HAD ELECTED NOT TO WRITE THIS UP DUE TO LACK OF SPARES. 3) THE ALT ALERT HAD BEEN ACTIVATING RANDOMLY EVEN THOUGH ALT WAS CORRECT, LEADING TO A TENDENCY NOT TO BE AS ALERT TO IT (A "BOY CRIES WOLF" PROBLEM). AGAIN NOT WRITTEN UP DUE TO RANDOMNESS. AS OF THIS WRITING ALMOST A MONTH LATER, THE ACFT IS STILL FLYING WITH NO AUTOPLT PITCH AND A SICK ALT ALERTER. THIS IS IN VIOLATION OF MEL RULES AND SAFETY AND SHOULD NOT CONTINUE!

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  6. Accession Number: 147873
    Synopsis: HEADING DEVIATION WHEN A COMPASS WARNKNG WAS IGNORED.
    Narrative: WHILE PREOCCUPIED WITH OTHER COCKPIT DUTIES, WE HAD A HDG EFIS COMP WARNING (THIS IS COMMON IN FLT AND IS GENERALLY MOMENTARY). I CANCELLED WARNING AND WENT BACK TO WATCHING FOR TFC. ASSIGNED HDG WAS 340, I NOTICED WE WERE ON A 010 DEG HDG VSLY, SO I DISCONNECTED AUTOPLT AND RETURNED TO THE PROPER HDG BY VIS REFERENCE. THIS PARTICULAR WARNING LASTED ABOUT 7 MINS BEFORE CORRECTING ITSELF. MAYBE STRONG ELECTROMAGNETIC INTERFERENCE N OF OHARE. BY HABIT I CANCELLED WHAT IS NORMALLY A MOMENTARY WARNING, INSTEAD OF IMMEDIATELY IDENTIFYING AND CORRECTING THE PROB. THE WARNING SYS CRIES WOLF SO MANY TIMES THAT WHEN A WARNING THAT ACTUALLY NEEDED ATTN OCCURRED I IGNORED IT. AUTOMATION STRIKES AGAIN.

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  8. Accession Number: 205156
    Synopsis: FLC OF ACR WDB ACFT DEVIATED FROM ASSIGNED ALT BECAUSE OF AN ACFT TCASII EQUIP ALERT
    Narrative: INITIAL CLRNC TO FL230 FOLLOWED BY CLRNC TO FL250. WHILE LEVEL AT FL250 AWAITING CLRNC TO CRUISING ALT I WAS LOOKING OUTSIDE WHEN TCASII GAVE A TA. I GLANCED AT THE TCASII THE TFC WAS 11 TO 11:30 (-19) 1900 FT BELOW US (I MAY NOT HAVE SEEN A MINUS SIGN THIS WAS HAPPENING FAST) AND DSNDING. IT APPEARED TO BE 10 MI AWAY AS I THOUGHT THE TCASII WAS ON A 40 MI RANGE BUT LATER LEARNED IT WAS ON 5 MI. WITHIN 2 SECONDS OF THE TA AN RA SOUNDED WITH A 2 WORD COMMAND WHICH I DID NOT HEAR CLRLY FOLLOWED BY THE WORD 'CLB.' I DISCONNECTED THE AUTOPLT AND INCREASED THE PITCH ATTITUDE AUTO THROTTLES BROUGHT THE PWR UP. THE CAPT WAS ABOUT TO ADVISE ATC OF OUR ACTIONS WHEN ATC ADVISED US TO 'MAINTAIN FL250.' HE ADVISED WE WERE RESPONDING TO AN RA AND CLBING. AT FL257 'CLB' CHANGED TO A COMMAND TO 'DSND.' THE ACFT REACHED FL258 PRIOR TO THE INITIATION OF THE DSCNT. AS SOON AS A RATE OF DSCNT WAS ESTABLISHED TCASII WAS SILENT AND WE LEVELED AT FL250. OAKLAND ADVISED OUR COMPANY THAT WE MISSED THE TFC LEVEL AT FL260 BY 1 MI AND 200 FT. TCASII PROVIDES US WITH APPARENTLY FALSE AND DISTRACTING WARNINGS ON A DAILY BASIS, AND NOW HAS COMMANDED US TO A NEAR MISS.

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  10. Accession Number: 217774
    Synopsis: AN LGT ACR CREW HAD A FALSE TCASII ALERT AT THE SAME TIME THAT THEIR CLRNC WAS BEING CHANGED TO A DEP THAT WAS NOT IN THEIR FMC DATA BASE.
    Narrative: DEPARTING LAX, RWY 25R, CLRED FOR LOOP 9. AFTER TKOF, DEP CTL TURNED US TO HDG 160 DEGS WHICH IS NOT THE NORMAL LOOP 9 HDG. A FEW MINS LATER, HE TOLD US THAT WE WERE ON THE LAXX 1 DEP AND WOULD BE TURNING TO SLI SOON. WHEN TURNED TO SLI, WE WERE CLRED TO 'SEAL BEACH AND THE DAGGETT TRANSITION.' SINCE THE LAXX 1 IS NOT IN THE FMC DATA BASE, AND SINCE WE WERE VERY CLOSE TO SLI, I ENTERED SLI, DIRECT DAG. AT THE SAME TIME, WE SWITCHED THE TCASII FROM TA TO TA/RA AND GOT AN IMMEDIATE FULL DOWN RA WHICH WAS OBVIOUSLY A 'GLITCH,' BUT WHICH WAS STILL DISTRACTING. AFTER PASSING SLI, THE CTLR ASKED US WHERE WE WERE GOING, AND WE, OF COURSE, REALIZED THAT SOMETHING WAS AMISS. WE CHKED THE LAXX 1 DEP PAGE AND DISCOVERED THE 'DOG LEG' BTWN SLI AND DAG. THE CTLR SEEMED TO BE UNCONCERNED, AND CLRED US DIRECT TO LAS. THIS WAS A TYPICAL 'COMBINATION OF INGREDIENTS' ERROR WHICH IS WHAT LEADS TO ACCIDENTS. SUPPLEMENTAL INFO FROM ACN 217471: THIS WAS A TYPICAL EXAMPLE OF MULTIPLE INPUTS IN A SHORT TIME. HAVING THE LAXX 1 DEP IN THE DATA BASE WOULD HAVE BEEN A BIG HELP IN AVOIDING THIS SITUATION. TCASII FALSE RA WAS A MAJOR DISTR TO NORMAL OPS IN THIS CASE POINTING OUT THE IMPORTANCE OF WORKING OUT ALL 'BUGS' IN THIS SYS.

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  12. Accession Number: 356736
    Synopsis: GPWS RECEIVED BY FLC IN AN MD80 IN A NIGHT OP. ACFT WAS AT MINIMUM VECTORING ALT (MVA) ON A RADAR VECTOR. EVASIVE ACTION CLB EXECUTED. N90 APCH CTLR RECLRS THEM BACK TO 4000 FT. STATES THAT OTHER FLTS, SAME ACR, HAVE HAD SIMILAR EVENTS IN THAT AREA. FLC ATC REVIEW WITH SUPVR REVEALED THAT THEY WERE INDEED ON AN MVA ALT THAT HAD TERRAIN CLRNC AUTH.
    Narrative: TIME: XX00Z/ATC FREQ, 132.74. ATC FACILITY: NY APCH. LOCATION: 25 NM NW OF SWF. APPROX 25 MI NW OF SWF, DURING RADAR VECTORS FROM APCH AT 4000 FT LEVEL WITH AUTOPLT ON, RECEIVED A GPWS TERRAIN WARNING. EXECUTED ESCAPE MANEUVER CLBING TO 5200 FT. WARNING STOPPED ONCE CLB WAS INITIATED. CONFIRMED WITH APCH THAT 4000 FT WAS MINIMUM VECTORING ALT AND DSNDED BACK TO 4000 FT. ON THE GND I TALKED TO NY APCH CTL SUPVR AND HE SAID THIS HAS OCCURRED BEFORE IN THIS AREA WITH OTHER OF OUR ACR FLTS. SUPPLEMENTAL INFO FROM ACN 356944: IN IMC CONDITIONS. WE GOT A GPWS TERRAIN WARNING. CAPT EXECUTED ESCAPE PROC CLBED TO 5200 FT AND LEVELED. CONFIRMED WITH APCH CTL VECTORING ALT AND DSNDED BACK TO 4000 FT. I WAS THE PNF.

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  14. Accession Number: 357194
    Synopsis: MLG ACFT ON VECTORS AND DSCNT CLRNCS RECEIVED GPWS 'TERRAIN' WARNING AND COMPLIED WITH PROCS OF APPLYING MAX THRUST AND PITCH UP 15 DEGS UNTIL WARNING CEASES. FLC ADVISED ATC OF MANEUVER AND CONTACTED THEM AFTER LNDG.
    Narrative: DURING THE DSCNT, IN NIGHT VFR CONDITIONS ON A FLT FROM LAX-LAS APCH CTL ISSUED VECTORS OFF OF THE (CRESO 3 ARR) AND SPD 210 KTS. A VISUAL APCH FOR RWY 25L WAS TO BE EXPECTED. A CLRNC WAS ISSUED TO DSND TO 8000 FT, WHILE ON DOWNWIND. TERRAIN AND ARPT IN SIGHT, A HDG OF 030 DEGS WAS ASSIGNED AND ANOTHER DSND CLRNC TO 6100 FT WAS ISSUED. THE AUTOPLT AND AUTOTHROTTLE WERE STILL ENGAGED. THE DSND WAS INITIATED USING (LEVEL CHANGE MODE). AT APPROX 6400 FT THE GPWS WARNING 'TERRAIN, TERRAIN' SOUNDED. I IMMEDIATELY DISENGAGED THE AUTOPLT AND AUTOTHROTTLE AND INITIATED THE IMMEDIATE ACTION PROC (WHICH CALLS FOR IN ADDITION TO DISCONNECTING THE AUTOPLT AND AUTOTHROTTLE, CALLS FOR MAX THRUST AND INITIAL PITCH OF 15 DEGS ANU). AT APPROX THE SAME TIME ATC WAS ADVISED OF THE CLB. THE GPWS WARNING STOPPED AT APPROX 7500 FT. ATC SAID THAT THE MVA WAS 6100 FT AND ASKED HOW HIGH WE NEEDED TO CLB. AT THAT POINT HE WAS ADVISED THAT THE GPWS WARNING HAD STOPPED AND WE CAN MAINTAIN PRESENT ALT (7800 FT). ATC APPROVED AND ASSIGNED US A HDG OF 010 DEGS AND POINTED OUT THE TFC WE WERE TO FOLLOW TO THE ARPT, ONCE TFC WAS IN SIGHT WE CALLED IT AND THE ARPT IN SIGHT AND WE WERE CLRED FOR THE VISUAL RWY 25L APCH. THE APCH AND LNDG WAS UNEVENTFUL. I CONTACTED APCH CTL SUPVR AND WAS TOLD THAT THE ALT THEY NORMALLY ISSUE IS 6500 FT FOR THE TFC IN THAT SECTOR. I EXPLAINED THAT WE HAD TO FOLLOW OUR PROC FOR A GPWS WARNING. HE SAID NO FURTHER ACTION IS REQUIRED, I THANKED HIM FOR HIS TIME AND HE THANKED ME FOR CALLING. WE HUNG UP. I THINK THAT A HEADING WITH MORE EASTERLY DIRECTION MAY HAVE PREVENTED THE GPWS WARNING, AND OF COURSE A HIGHER ALT ON DOWNWIND (HIGHER THAN 6100 FT) WOULD'VE HELPED ALSO. TFC CONFLICT WITH TFC OVERHEAD COULD HAVE RESULTED DURING OUR CLB TO ESCAPE THE WARNING. LUCKILY THE AREA ABOVE WAS CLR OF TFC. I AM SURE THAT THE RATE OF DSCNT WAS A FACTOR IN THIS SIT, BUT THE AIRPLANE WAS ON A NORMAL (LEVEL CHANGE) DSCNT. WE HAD THE TERRAIN IN SIGHT THE WHOLE TIME. BUT IT WAS NIGHTTIME AND OUR PROC CALLS FOR THE TYPE OF RECOVERY WE USED DURING THIS SIT. MAYBE OUR PARTNERS AT APCH CTL SHOULD HAVE THE GPWS WARNINGS AND WHAT TRIGGERS THEM EXPLAINED IN MORE DETAILS.

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  16. Accession Number: 357571
    Synopsis: A CL65 DSNDING TO BNA RECEIVES A GPWS ALARM AT 2400 FT AND CLBS TO 4600 FT. ANOTHER APCH WAS MADE WITHOUT FURTHER INCIDENT.
    Narrative: DURING THE APCH AT KNOXVILLE ON THE ILS RWY 23R TURNING ON TO THE APCH WE ENCOUNTERED A GND PROX WARNING. BOTH PLTS PULLED UP ON THE YOKE AND THE CTLR WAS TOLD OF OUR GPWS. HE CLRED US TO 4000 FT BY THE TIME WE GOT THE PLANE TO LEVEL OFF WE WERE THROUGH 4600 FT. WE LEVELED THE ACFT AT 4000 FT AND TRIED ANOTHER APCH TO KNOXVILLE WITH NO GPWS THIS TIME. DON'T KNOW WHAT CAUSED THE GPWS OR WHY.

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  18. Accession Number: 366583
    Synopsis: B767 ON NORTH ATLANTIC RTE AT FL350 WITH NEW MINIMUM ALT SEPARATION GOT A TCASII TA ON ANOTHER B767 AT FL340 ON SAME RTE. RPTR LEARNS FROM CONTACT WITH OTHER ACFT THAT THEY ALSO HAVE TA AND ARE FLYING AT MACH PT 80. RPTR REQUESTS AND RECEIVES APPROVAL FOR MACH PT 81. ADVISORIES STOPPED WHEN RPTR'S ACFT GOT AHEAD OF THE OTHER ACFT. RPTED THAT THE ADVISORIES LASTED FOR ABOUT 30 MINS. RPTR STATED THE OTHER ACFT WAS GOING TO OR ALREADY HAD TURNED OFF THE TCASII TO KEEP FROM GETTING THE CONSTANT ADVISORIES.
    Narrative: NEW MINIMUM ALT SEPARATION ON NORTH ATLANTIC RTES AND TCASII ROUTING: STEAM OYSTR 55N 050W 57N 040W 58N 030W 57N 020W 56N 010W MAC. FL350 MACH .80 B767-300. APPROX 12 MINS PRIOR TO STEAM, OBSERVED ANOTHER ACFT APCHING STEAM FROM A DIFFERENT ANGLE (10 DEGS OR SO), BELOW OUR ALT. APPROX 10 MINS PRIOR TO STEAM, RECEIVED VERBAL 'TFC' AND YELLOW TCASII TA. CHKED OUR ALT AT FL350. TCASII HAD TFC AT FL340. TALKED TO OTHER ACFT (ANOTHER B767) AND FOUND HE HAD SAME ROUTING AND ASSIGNED MACH .80. ALSO, HE TOO WAS RECEIVING TCASII TA. AFTER APPROX 15 MINS OF CONTINUOUS YELLOW TA AND OCCASIONAL VERBAL 'TFC,' REQUESTED AND RECEIVED CLRNC TO MAKE XING AT MACH .81. ONCE WE GOT AHEAD OF OTHER B767, THE TCASII TA VERBAL AND YELLOW ADVISORIES STOPPED. TOTAL TIME OF CONTINUOUS TCASII TA YELLOW WAS APPROX 30 MINS. WHILE TALKING TO OTHER ACFT, HE INDICATED THAT HE WAS GOING TO OR ALREADY HAD TURNED OFF HIS TCASII TO KEEP FROM GETTING CONSTANT ADVISORIES. A POTENTIAL PROB EXISTS: SOMEBODY IS GOING TO TURN OFF THIS SAFETY EQUIP AND JEOPARDIZE HIS AND OTHER ACFT. ALSO, HAS ANYONE SERIOUSLY THOUGHT ABOUT WHAT HAPPENS WHEN SOMEONE GETS AN RA? THE POTENTIAL EXISTS FOR A LOT OF ACFT TO BE SCATTERED THROUGHOUT A LOT OF ALTS OUT THERE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR INDICATED A RPT TO THE UNION AND TO THE COMPANY ABOUT THE TCASII TA'S. RPTR STATED HE HAD HEARD THAT THERE WILL BE SOFTWARE CHANGE NEXT YR TO TAKE CARE OF THE PROB. RPTR SAID HE WAS SCARED THAT PLTS MIGHT TURN OFF THEIR TCASII AND INDICATED THIS COULD BE MORE OF A PROB FOR ACFT AVOIDANCE. RPTR HAS NOT HAD THE PROB RECUR BUT HAS TALKED TO OTHERS THAT HAVE.

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  20. Accession Number: 372270
    Synopsis: FLC OF A BEECH, BE02, MODEL 1900 AIRLINER, OVERSHOT ALT ON DSCNT DUE TO ALT ALERTER PROB. THE FLC WAS CORRECTING BACK AS ATC INTERVENED TO REMIND THEM OF THEIR ASSIGNED ALT.
    Narrative: AFTER DEPARTING PALM BEACH INTL ARPT, THE ALT ALERTER BEGAN SOUNDING SPORADICALLY IN ADDITION TO THE NORMAL 1000 FT TO GO ALERT. THIS HAPPENED CONTINUOUSLY THROUGHOUT THE FLT DURING CLB, ENRTE PHASE AND DSCNT. AS WE APCHED JAX I MADE THE '1000 FT TO GO' CALLOUT AS WE DSNDED THROUGH 8000 FT FOR OUR ASSIGNED ALT OF 7000 FT. I ALSO GAVE COM #1 TO MY FO WHO WAS THE PF AS I WENT TO COM #2 TO GET THE NEW ATIS. AS I CAME BACK TO COM #1, I NOTICED MY FO HAD SLOWED HIS RATE OF DSCNT AS HE APCHED 7000 FT SO I GAVE HIM THE CURRENT ATIS WHILE THE ALT ALERTER CONTINUED ITS ERRATIC CHIMING. ALSO, ABOUT THIS TIME, I WAS POINTING OUT JAX IN THE DISTANCE AS MY FO DID NOT YET SEE THE ARPT. I THEN REALIZED HE HAD DSNDED THROUGH 6800 FT AND NOTIFIED HIM OF THIS. HE STARTED HIS CLB BACK TO OUR ASSIGNED ALT AT 6700 FT. ATC AT THAT POINT REITERATED OUR ASSIGNED ALT AND POINTED OUT TFC AT OUR 10 O'CLOCK POS AND 1000 FT BELOW US WHICH WE CONFIRMED WE ALREADY HAD ON TCASII AND VISUALLY. NEEDLESS TO SAY THE ALT ALERTER WAS WRITTEN UP AS INOP AS SOON AS WE LANDED. OUR DSCNT 300 FT BELOW OUR ASSIGNED ALT WAS BASICALLY ATTRIBUTABLE TO THE FACT THAT AFTER 1 HR 10 MINS OF LISTENING TO THE ALT ALERTER CHIME INCESSANTLY, WE BECAME DISENGAGED FROM ITS USEFULNESS AS A WARNING TOOL. IN THE FUTURE, IF THIS HAPPENS WITH THE ALT ALERTER, I WILL DEFINITELY WAIT UNTIL LEVEL AT THE ASSIGNED ALT BEFORE GETTING ATIS, POINTING OUT ARPTS, ETC.

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  22. Accession Number: 387512
    Synopsis: FLC OF B757 HAS TCASII RA AND DSNDS ONLY TO FIND THEMSELVES HEAD ON WITH TFC AT ANOTHER ARPT. A CLB RA IS RECEIVED AND THEY CLB.
    Narrative: ON VECTORS TO LAX N COMPLEX (RWY 24) MY B757 WAS ON AUTOFLT, FLAPS 20 DEGS, SPD 160 KTS, 2500 FT MSL, JUST STARTING R BASE TURN WHEN TCASII GAVE SUDDEN RA TO 'DSND NOW.' AUTOFLT WAS DISCONNECTED IMMEDIATELY AND DSCNT BEGUN WITH GUIDANCE FROM VSI. ONCE CLR OF CONFLICT (ALT LOSS 400 FT) WE RECEIVED AN IMMEDIATE CLB RESOLUTION DUE TO NOW BEING HEAD-ON WITH TFC ON APCH TO ANOTHER LAX AREA ARPT. (WE BELIEVE THE OTHER ACFT WAS INBOUND TO SMO ARPT.) MANUAL THRUST WAS APPLIED ALONG WITH A CLB TO CLR THIS CLB RESOLUTION. APCH WAS CONTINUED WITH A CLOSE-IN ILS RWY CHANGE TO A SUCCESSFUL LNDG AT LAX. BOTTOM LINE: A FALSE TCASII RESOLUTION PUT OUR ACFT INTO A REAL TFC CONFLICT AND RESOLUTION. THIS IS THE SECOND FALSE RESOLUTION I HAVE EXPERIENCED IN OUR B757 ACFT IN 8 MONTHS TIME.

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  24. Accession Number: 389453
    Synopsis: B767-200 ACFT ON OCEANIC RTE RECEIVED FALSE TCASII WARNING. RPTR CAPT ASSUMED IT WAS FALSE AND TOOK NO EVASIVE ACTION. THE TCASII PROB IS REPORTEDLY CAUSED BY FAILURE OF THE SUPPRESSION BUS WHICH INHIBITS TCASII FROM RESPONDING TO ITS OWN ACFT.
    Narrative: THIS IS A RPT OF A TYPE OF TCASII FAILURE WHICH IS NOT NORMALLY SEEN. NO TRAINING IN THE FAILURE MODE WAS GIVEN TO ANY OF OUR CREWS. IT WILL HAPPEN AGAIN. I TOOK NO EVASIVE ACTION. ENRTE AT CRUISE ALT IN RVSM/MNPS WE RECEIVED A TCASII RESOLUTION TO DSND. THIS WAS FOLLOWED WITH A TCASII COMMAND TO INCREASE DSCNT RATE. THE RATES COMMANDED WERE 1500 FPM FOLLOWED BY THE RATE OF 2500 FPM. THE PROB WAS: THE TARGET WHICH WAS CREATING THE RESOLUTION WAS A FALSE TARGET. THE THREAT WAS A TARGET WHICH APPEARED FROM BEHIND OUR ACFT AND SHOWED ZERO ALT DIFFERENCE FROM OUR ACFT. I DID NOT RESPOND TO THE WARNING. IT APPEARED TO ME TO BE A FALSE TARGET. I HAVE SEEN FALSE TARGETS IN THE PAST ON THE B767 FLEET. IN THOSE CASES THE TARGET WOULD APPEAR AND ONLY SHOW THE YELLOW BALL SYMBOL. IN THIS CASE THE TARGET CHANGED FROM THE YELLOW BALL SYMBOL TO THE RED SQUARE AS THE RESOLUTION COMMAND WAS ISSUED. WHEN THE BALL SYMBOL APPEARED THE 'TFC, TFC' WARNING WAS ISSUED. WITH THE RED SQUARE DISPLAY THE 'DSND' AND 'INCREASE DSCNT' COMMANDS WERE GIVEN. MY CONCERN IS THE TRAINING WE ARE GIVING TO THE CREWS IS TO RESPOND IMMEDIATELY TO TCASII RESOLUTIONS. I WAS NOT AWARE THAT THERE IS A FAILURE MODE WHICH COULD CREATE A RESOLUTION. A TCASII RESPONSE IN RVSM AIRSPACE IS THE MOST SERIOUS PART OF THIS PROB. IN ATTEMPTING TO UNDERSTAND THIS PROB I HAVE BEEN WORKING WITH CAPT A AND MR B, MGR OF ACFT RELIABILITY. MR B ALSO ASKED THAT WE SPEAK WITH COMMERCIAL RADIO. COMMERCIAL RADIO IS THE POINT OF CONTACT FOR LOGGING RVSM PROBS. THIS FAILURE MODE IS NOT UNKNOWN TO THIS UNIT. IT CAN BE SEEN IF THERE IS A FAILURE OF THE SUPPRESSION BUS. THAT BUS IS USED TO MAKE THE TCASII NOT RESPOND TO THE ACFT ITSELF. MY ACR HAS ASKED ROCKWELL COLLINS TO EVALUATE THE TCASII COMPUTER AND THE XPONDER. I SPOKE WITH MR C OF ROCKWELL COLLINS ABOUT THIS TYPE OF FAILURE. HE CONCURS WITH THE THEORY THAT THE SUPPRESSION BUS IS THE PROB. MR C ALSO ADVISED THAT NEITHER THE XPONDER NOR THE TCASII COMPUTER WILL NORMALLY BE THE PROB. SEVERAL YRS AGO, IN THE EARLY TCASII INSTALLATIONS WIRING IN THE SUPPRESSION BUS CAUSED THE PROBS. I BELIEVE WE NEED TO ADVISE ICAO OF THIS FAILURE. SOMEONE IN ICAO IS MAINTAINING A DATABASE OF PROBS IN RVSM AIRSPACE. THERE IS A DEFINITE POTENTIAL FOR A SAFETY PROB WITH THIS FAILURE. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: CAPT RPTR STATES THAT POSTFLT REVEALED THAT THE TCASII UNIT HAD A SUPPRESSION BUS FAILURE WHICH RESULTED IN THE ACFT PICKING UP ITS OWN XPONDER AS AN INTRUDER. RPTR CONTACTED ROCKWELL COLLINS WHO IS THE MANUFACTURER AND THEY RPTED THAT, THOUGH RELATIVELY RARE, FALSE TCASII TARGETS WILL BE GENERATED IF THE SUPPRESSION BUS HAS A FAULT. REPORTEDLY, THE SUPPRESSION BUS FAILURES ARE USUALLY FOUND ON OLDER ACFT WHEN CORROSION CAUSES THE PROB. RPTR STATES THAT TRANS-OCEAN FLYING INVOLVES OTHER FACTORS WHICH, IN CONJUNCTION WITH THIS TYPE OF FAILURE COULD RESULT IN FUTURE ATC PROBS, ESPECIALLY IN THE RVSM SEPARATION SIT. THE FLC FLYING OVER TO EUROPE IS ON THE BACK SIDE OF THE CLOCK AND WHEN THEY RETURN THEY ARE FATIGUED. THEN, IF THE CAPT IS OUT OF THE COCKPIT FOR CREW REST AND 2 FO'S IN THE SEATS, WITH A FALSE TCASII AND TFC IN THE VICINITY, COULD EASILY RESULT IN NMAC. THE SPECIFIC TCASII FAILURE OF PICKING UP ITS OWN XPONDER ALWAYS SHOWS THE INTRUDER TARGET SUPERIMPOSED AT THE ACFT POS. RPTR'S CONCERN IS THAT ACFT WITH ONLY 1000 FT SEPARATION, A FASTER ACFT OVERTAKING THE LEAD ACFT AND PASSING EITHER BELOW OR OVER LEAD ACFT COULD RESULT IN A TCASII RA WHICH COULD PUT THE 2 ACFT TOGETHER.

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  26. Accession Number: 399839
    Synopsis: AN MD80 DROPS BELOW THE TCA CLASS B ALT OF 2000 FT WHEN 9 MI FROM IAH DURING AN ILS APCH TO RWY 8. THE ACFT HAD BEEN CLRED TO 3000 FT AND CLRED FOR THE ILS. THE LOM XING ALT WAS PUBLISHED AS 2000 FT. CREW WAS DISTR BY 'A SLOW MAIN GEAR' EXTENSION. CAPT CITES AN ALT GS CAPTURE FAILURE ON HIS AUTO FLT SYS AS CAUSAL.
    Narrative: FLT WAS VECTORED TO FINAL APCH COURSE AND CLRED TO DSND TO 3000 FT AND CLRED FOR ILS RWY 8 APCH. LOC CAPTURED AND FLT GUIDANCE/AUTOPLT WAS PROPERLY ARMED FOR ALT CAPTURE AND LOC AND GS CAPTURE. THE FLT GUIDANCE SYS EITHER FAILED TO CAPTURE THE 3000 FT ALT OR LOST THE CAPTURE. LIKEWISE WITH THE GS CAPTURE. DURING THE TIME OF GS CAPTURE AT 3000 FT THE PLTS WERE DISTR BY A SLOWER GEAR EXTENSION ON 1 LNDG GEAR. DSCNT CONTINUED BELOW THE 2000 FT MINIMUM ALT. 1 ALT ALERT WARNING WAS RECEIVED. HOWEVER, THIS IS NORMAL WHEN THE CORRECT MISSED APCH ALT IS SET AND AFTER GS IS CAPTURED. WE NOTED WE WERE BELOW OUR 2000 FT ALT AT ABOUT 1400 FT MSL AND TWR ALSO CALLED TO GIVE US OUR LOW ALT WARNING. WE CORRECTED, BOTTOMING OUT AT ABOUT 1200-1300 FT MSL. WE CLBED TO REINTERCEPT THE GS FOR REMAINDER OF APCH. LESSONS LEARNED: CLOSER MONITORING OF FLT GUIDANCE STATUS, ESPECIALLY WHEN SOMETHING DIVERTS ATTN AWAY FROM MONITORING. CHANGE MD80 FLT ALT WARNING SYS SO THAT IT IS NOT NORMAL TO RECEIVE AND DISREGARD AN ALT ALERT WARNING DURING FINAL APCH. ALSO, LNDG CHKLIST CALLS FOR CAPT (PF) TO VERIFY GEAR POS. IN THIS CASE, WE WERE BOTH WAITING FOR AND MONITORING THE RED GEAR WARNING LIGHT.

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  28. Accession Number: 410605
    Synopsis: ACR FLC BECOME DISTR ON FINAL APCH AND FORGET TO LOWER GEAR. GPWS CONTINUES TO ALARM, ALERTING THE FLC TO THE NO GEAR SIT. PIC EXECUTES GAR.
    Narrative: ON APCH TO RWY 18L IN CVG, INTERCEPTED GS SEVERAL MI OUTSIDE THE FAF IN VFR CONDITIONS. FIELD WX HAD BEEN 3 MI. AS WE APCHED THE OM, THE FIELD WX WENT TO 5000 FT RVR. IN ATTEMPTING TO ADJUST SPD FOR TFC, ADJUST FOR THE CHANGING WX, ETC, WE FAILED TO LOWER THE GEAR OR COMPLETE THE LNDG CHKLIST. AS WE BROKE OUT, THE 'TERRAIN' GPWS WARNING SOUNDED, BUT AS WE HAD THE FIELD VISUALLY, WE AT FIRST ASSUMED A FAULTY GPWS. WE THEN RECOGNIZED THE GEAR PROB, EXECUTED A NORMAL MISSED APCH, AND RETURNED TO LAND WITHOUT INCIDENT. CONTRIBUTING FACTORS WERE: HIGH WORKLOAD IN CRITICAL PHASE OF APCH AND KNOWLEDGE (CVG COMMERCIAL CHART PAGES) THAT GPWS WARNINGS ON APCH IN CVG ARE NOT UNCOMMON, CAUSING A SLIGHT DELAY IN EXECUTION OF MISSED APCH.

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  30. Accession Number: 415625
    Synopsis: AN ARR ATR72 FLC LEAVES THEIR ASSIGNED ALT OF 5000 FT WHEN RECEIVING A TCASII RA. WHILE ADVISING APCH CTLR OF SAME, CTLR ADVISES CREW TO RETURN TO 5000 FT BECAUSE OF XING TFC AT 6000 FT. MISS DISTANCE WAS 3000 FT HORIZ AND 550 FT VERT.
    Narrative: WHILE ON APCH TO RWY 17C AT DFW, TCASII GAVE AN IMMEDIATE 'CLB NOW' RA WITH VSI INDICATION OF 1500 FPM CLB. WHILE RESPONDING TO THE RA, WE CLBED TOWARDS AN MD80 1000 FT ABOVE OUR ALT. NOTIFIED ATC WE WERE RESPONDING TO THE RA. WE WERE TOLD OF THE CONFLICT, RETURNED TO OUR ASSIGNED ALT OF 5000 FT. TOTAL DEV OF 500 FT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: THE CAPT RPTR, PNF, COULD NOT TELL THE ANALYST WHAT MAKE OF TCASII THEY HAD INSTALLED ON THE ATR72. HE DOES, HOWEVER, BELIEVE IT WAS A FALSE WARNING, A GHOST. THE TFC WAS INDICATED AT THE SAME ALT AS THEIR ACFT AND THE TCASII HAD NOT ISSUED A TA PRIOR TO THE ISSUANCE OF THE RA. ATC DID NOT SEE ANY TFC BELOW OR AT THE SAME ALT. AT THAT TIME THOUGH, THERE WAS A LOT OF TSTM ACTIVITY IN THE AREA, WHICH WAS A DISTR TO BOTH THE FLCS AND ATC. THE ACFT WAS IMC AT THE TIME AND THAT WAS ONE REASON FOR THE ALTDEV ALT EXCURSION AND NON ADHERENCE TO ATC CLRNC. THE CAPT NOTED TFC 'EVERYWHERE' AND THEY WERE ON VECTORS AFTER A HECTIC WX WHIPPED FLT FROM LITTLE ROCK. THE CREW WAS TASK SATURATED. THE CAPT WAITED FOR THE THIRD RA BEFORE HE INSTRUCTED THE FO TO CLB WITH THE RA SINCE HE FELT THAT THE TCASII SOMETIMES SETTLES DOWN AFTER A FALSE 'BLURP' OR TWO. THE CAPT ADVISED ATC WHO JUST ABOUT 'CAME OUT OF HIS CHAIR' AND SAID, 'DON'T CLB, THERE'S XING TFC ABOVE YOU AT 6000 FT.' THE ATR72 THEN POPPED OUT OF THE CLOUD AT ABOUT 5500 FT AND SAW THE XING TFC. A WK LATER THE CAPT CALLED THE TRACON SUPVR AND DISCUSSED THE MATTER WITH HIM. THE SUPVR SAID THAT THE ACFT AT 6000 FT DID GET AN RA ON THE ATR72 AND HAD STARTED A CLB AS WELL. A REAL BUMP UP OP. SUPPLEMENTAL INFO FROM ACN 415626: WE NOTIFIED ATC OF THE RA AND DEV AND WAS INSTRUCTED TO DSND IMMEDIATELY FOR XING TFC.
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