|37000 Feet||Browse and search NASA's
Aviation Safety Reporting System
|Local Time Of Day||0601 To 1200|
|Locale Reference||atc facility : cie|
|Altitude||msl bound lower : 39000|
msl bound upper : 39000
|Controlling Facilities||artcc : zab|
|Operator||common carrier : air carrier|
|Make Model Name||Widebody, Low Wing, 2 Turbojet Eng|
|Navigation In Use||Other |
|Flight Phase||cruise other|
|Affiliation||company : air carrier|
|Function||flight crew : first officer|
|Qualification||pilot : flight engineer|
pilot : atp
|Experience||flight time last 90 days : 200|
flight time total : 6000
flight time type : 500
|Affiliation||company : air carrier|
|Function||flight crew : captain|
oversight : pic
|Qualification||pilot : atp|
|Anomaly||non adherence : clearance|
|Independent Detector||other controllera|
|Resolutory Action||controller : issued new clearance|
|Primary Problem||Flight Crew Human Performance|
|Air Traffic Incident||Pilot Deviation|
On 4/sun/89 I was acting as first officer (PNF) on a scheduled air carrier flight between dfw-tus on a widebody transport. During cruise flight at FL390 in the vicinity of cie VOR ZAB cleared us to, 'FL240, pilot's discretion leaving FL370.' after reading back the clearance I left the radio frequency to copy the tus ATIS. When I finished. I noticed the captain had not begun his descent from FL390. I immediately questioned this and simultaneously ZAB requested that we begin our descent 'now.' after acknowledging the clearance I felt certain the captain would initiate the descent. The aircraft was being flown on autoplt and the captain would initiate the descent. The aircraft was being flown on autoplt and the captain was programming the FMC for descent. However, since our cruise speed was .83 M and the selected descent speed was .80 M, the autoplt controled descent would not commence until our speed had bled off to .80 M. This speed reduction was occurring at level flight. Meanwhile, center issued us a clearance to turn immediately 40 degrees to the right of course. Although this turn was to avoid possible traffic conflict, I do not believe an actual conflict nor near missed occurred. For some reason the captain apparently did not understand our clearance from center or did not realize that the autoplt was reducing speed during level flight. My distraction from the descent to copy ATIS was purely unintentional in that I assumed the captain would begin descent immediately.
Original NASA ASRS Text
Title: AFTER RECEIVING DESCENT CLRNC REPORTER FLT FAILED TO BEGIN THE DESCENT IN A TIMELY MANNER. AS A RESULT ATC HAD TO ISSUE A RADAR VECTOR TO MAINTAIN SEPARATION.
Narrative: ON 4/SUN/89 I WAS ACTING AS F/O (PNF) ON A SCHEDULED ACR FLT BTWN DFW-TUS ON A WDB. DURING CRUISE FLT AT FL390 IN THE VICINITY OF CIE VOR ZAB CLRED US TO, 'FL240, PLT'S DISCRETION LEAVING FL370.' AFTER READING BACK THE CLRNC I LEFT THE RADIO FREQ TO COPY THE TUS ATIS. WHEN I FINISHED. I NOTICED THE CAPT HAD NOT BEGUN HIS DSCNT FROM FL390. I IMMEDIATELY QUESTIONED THIS AND SIMULTANEOUSLY ZAB REQUESTED THAT WE BEGIN OUR DSCNT 'NOW.' AFTER ACKNOWLEDGING THE CLRNC I FELT CERTAIN THE CAPT WOULD INITIATE THE DSCNT. THE ACFT WAS BEING FLOWN ON AUTOPLT AND THE CAPT WOULD INITIATE THE DSCNT. THE ACFT WAS BEING FLOWN ON AUTOPLT AND THE CAPT WAS PROGRAMMING THE FMC FOR DSCNT. HOWEVER, SINCE OUR CRUISE SPD WAS .83 M AND THE SELECTED DSCNT SPD WAS .80 M, THE AUTOPLT CTLED DSCNT WOULD NOT COMMENCE UNTIL OUR SPD HAD BLED OFF TO .80 M. THIS SPD REDUCTION WAS OCCURRING AT LEVEL FLT. MEANWHILE, CENTER ISSUED US A CLRNC TO TURN IMMEDIATELY 40 DEGS TO THE RIGHT OF COURSE. ALTHOUGH THIS TURN WAS TO AVOID POSSIBLE TFC CONFLICT, I DO NOT BELIEVE AN ACTUAL CONFLICT NOR NEAR MISSED OCCURRED. FOR SOME REASON THE CAPT APPARENTLY DID NOT UNDERSTAND OUR CLRNC FROM CENTER OR DID NOT REALIZE THAT THE AUTOPLT WAS REDUCING SPD DURING LEVEL FLT. MY DISTR FROM THE DSCNT TO COPY ATIS WAS PURELY UNINTENTIONAL IN THAT I ASSUMED THE CAPT WOULD BEGIN DSCNT IMMEDIATELY.
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.