|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0601 To 1200|
|Locale Reference||atc facility : ord|
|Altitude||agl bound lower : 0|
agl bound upper : 0
|Controlling Facilities||tracon : ord|
|Operator||common carrier : air carrier|
|Make Model Name||Medium Large Transport, Low Wing, 2 Turbojet Eng|
|Navigation In Use||Other|
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : atp|
|Experience||flight time last 90 days : 180|
flight time total : 10000
flight time type : 1500
|Function||controller : approach|
|Qualification||controller : radar|
|Anomaly||other anomaly other|
|Independent Detector||other other : unspecified|
|Primary Problem||Flight Crew Human Performance|
|Air Traffic Incident||other|
Complaints from several ATC facs have identified that medium large transport crews are missing a high number of radio calls during the descent and approach phases of flight. A recent 'windy city newsletter' alluded to this fact. Informal polling of medium large transport 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. Often when 1 pilot attempts to do too much the work flow is disrupted to the point where neither is sure what has been accomplished. A pilot doing this, though motivated by the desire to do a better job, usually causes the other pilot to either lower his awareness or just take himself out of the loop. Missed calls! The low relative cockpit experience on the medium large transport could also be a factor in missing ATC calls except that the problem 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 pilot. The particulars of the medium large transport autoplt flight director system allows so many options, especially in descent, that the oversight responsibilities are greatly increased while a pilot new to the equipment 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 air carrier's medium large transport, also junior equipment, and even our widebody transport would share in the grief felt by ATC. Distraction seems to be the primary reason for missed radio calls on the medium large transport. This distraction, 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 airspeed 210 KTS or below it screams 'landing gear.' set the missed approach altitude, concentrate on flying a close approach and 'altitude' yells twice. The most common statement in an medium large transport cockpit during descent and approach 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 system to be the final evaluators as to its necessity. However, the design engineers seem to have the ability to sell the FAA a system west/O the input from those who will use it. At the very least, 'landing gear' should be associated with the radio altimeter, not airspeed. We can land at any speed though never west/O something to land on! Hopefully, all voice warnings will be reevaluated. Many aircraft have successfully completed thousands of cycles west/O CAWS technology. Missed calls are a real problem on the medium large transport. Be aware of it. Often just knowing a problem exists is a real step toward solving it. Remember, when you hear 'landing 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!'
Original NASA ASRS Text
Title: 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 DSCNT 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. OFTEN 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 DSCNT, 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 DSCNT 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 ENGINEERS 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!'
Data retrieved from NASA's ASRS site as of August 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.