Late descent causes conflict with another aircraft.

Attributes
ACN	96452
Time
Date	198810
Day	Tue
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : pit
State Reference	PA
Altitude	msl bound lower : 8800 msl bound upper : 10000
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Controlling Facilities	tracon : pit
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Make Model Name	Small Transport, Low Wing, 2 Recip Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 180 flight time total : 4000 flight time type : 1600
ASRS Report	96452
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : clearance non adherence : required legal separation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 5000 vertical : 0
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

At 10000' we were given a turn and a descent to 6000'. I dialed the new altitude into the altitude alert system and turned to the new heading. Then I remembered that the controller also wanted me to descend to 6000'. As I was passing 9000', the controller told me to immediately turn right and climb back to 10000', that there was an small transport at 9000' about 1 mi going opposite my direction. We told him that we had the aircraft in sight and the controller cleared us for further descent and cleared us for the approach. The controller didn't say anything else about the potential conflict and didn't seem upset at me or himself, but I thought it wise to send in this report. I learned that if I'm given a descent, do it now, not a few seconds later, because that airspace won't be clear later. Also, the final controller was busy and either forgot about the small transport or expected me to be down at 6000' before the small transport passed by.

Original NASA ASRS Text

Title: LATE DESCENT CAUSES CONFLICT WITH ANOTHER ACFT.

Narrative: AT 10000' WE WERE GIVEN A TURN AND A DSCNT TO 6000'. I DIALED THE NEW ALT INTO THE ALT ALERT SYS AND TURNED TO THE NEW HDG. THEN I REMEMBERED THAT THE CTLR ALSO WANTED ME TO DSND TO 6000'. AS I WAS PASSING 9000', THE CTLR TOLD ME TO IMMEDIATELY TURN RIGHT AND CLB BACK TO 10000', THAT THERE WAS AN SMT AT 9000' ABOUT 1 MI GOING OPPOSITE MY DIRECTION. WE TOLD HIM THAT WE HAD THE ACFT IN SIGHT AND THE CTLR CLRED US FOR FURTHER DSCNT AND CLRED US FOR THE APCH. THE CTLR DIDN'T SAY ANYTHING ELSE ABOUT THE POTENTIAL CONFLICT AND DIDN'T SEEM UPSET AT ME OR HIMSELF, BUT I THOUGHT IT WISE TO SEND IN THIS RPT. I LEARNED THAT IF I'M GIVEN A DSCNT, DO IT NOW, NOT A FEW SECONDS LATER, BECAUSE THAT AIRSPACE WON'T BE CLR LATER. ALSO, THE FINAL CTLR WAS BUSY AND EITHER FORGOT ABOUT THE SMT OR EXPECTED ME TO BE DOWN AT 6000' BEFORE THE SMT PASSED BY.

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.