After receiving descent clearance reporter flight failed to begin the descent in a timely manner. As...

Attributes
ACN	108361
Time
Date	198904
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : cie
State Reference	AZ
Altitude	msl bound lower : 39000 msl bound upper : 39000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zab
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	cruise other cruise other descent other
Flight Plan	IFR
Person 1
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
ASRS Report	108361
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : clearance
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

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.

After receiving descent clearance reporter flight failed to begin the descent in a timely manner. As a result ATC had to issue a radar vector to maintain separation.