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Incidents related to Issue 2 incidents related to this issue.

Issue: operational knowledge may be lacking in design process (Issue #121)
Description: Automation design may not take into consideration the operational knowledge of pilots. This may lead to designs that are counter-intuitive to pilots, possibly increasing pilot workload and the opportunity for error.

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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: 125410
    Synopsis: MLG IN HIGH RATE OF CLIMB OVERSHOT ASSIGNED ALT.
    Narrative: ON DEP WE WERE CLEARED TO CLIMB TO 12, 000', BUT WE HAD AN ALT DEVIATION AND WE CLIMBED TO 12,450' BEFORE RETURNING TO THE ASSIGNED 12,000'. AT 11,000' I CALLED "1000 TO GO" AND THEN LOOKED BACK OUTSIDE TO CLEAR FOR TFC IN THE TURN, I LOOKED BACK INSIDE AND SAW THAT WE WERE AT 11,800 CLIMBING AT APPROX 4000 FPM. I PUSHED FORWARD ON THE YOKE AT THE SAME TIME I SAID 12,000. THE CAPT THEN STARTED TO LEVEL OFF, GOING 450' ABOVE THE ASSIGNED ALT BEFORE RETURNING TO 12,000. THE DEP CTLR DID NOT MENTION THE ALT DEVIATION. THE REST OF THE FLT WENT WITHOUT INCIDENT. THE ACFT IS A POPULAR MODERN TRANSPORT WITH AN EXCELLENT THRUST TO WEIGHT RATIO, GLASS COCKPIT, AUTO THROTTLES, FMCS, THE WORKS. WITH THIS ACFT'S POWER IT HAS QUITE A GOOD CLIMB RATE AND THE AUTOMATED SYSTEMS FLY THE ACFT EXCEPTIONALLY WELL, BUT THEY DO NOT CLIMB OR DSND THE ACFT ACCORDING TO THE AIM. IT IS NOT AT ALL UNUSUAL TO APCH WITHIN 300-400' OF A SELECTED ALT AT 4000 FPM, THE COMPUTER WILL CAPTURE THE ALT WITH ABOUT A 1.25 G PULL OR A .75 G PUSHOVER SO THAT THE PAX WON'T REALLY FEEL IT. A 500 FPM RATE FOR THE LAST 1000' HAS TO BE DONE BY SELECTING THE VERTICAL SPEED MODE OR MANUAL FLT (NOT NORMALLY DONE) AFTER PRESELECTING THE OTHER VERTICAL MODES. THEREFORE, MOST PEOPLE WILL FOLLOW THE FLT DIRECTOR BARS TO CAPTURE THE ALT AND WILL USUALLY APCH AN ALT AT FAR GREATER A RATE OF CLIMB THAN THEY WOULD ACCEPT IN A LESS AUTOMATED ACFT. I FEEL THAT IF THE AIM DSNT RATES WERE PROGRAMMED INTO THE COMPUTER THAT WOULD BE A BETTER SYSTEM. THAT WAY HIGH VERTICAL SPEED IN THE LAST 1000' WOULD BE THE EXCEPTION AND NOT THE RULE AND MUCH MORE LIKELY TO RESULT N A TIMELY LEVEL OFF INSTEAD OF AN ALT BUST. AFTER ALL IT WOULD TAKE MORE THAN 30 SECONDS TO OVERFLY/UNDERFLY AN ALT BY THE MAGIC 300' AT 500 FPM AS OPPOSED TO ONLY SLIGHTLY MORE THAN 4 SECONDS IT WOULD TAKE AT 4000 FPM.
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