Less than standard separation between air carrier and commuter. Operational error.

Attributes
ACN	198363
Time
Date	199201
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : pit
State Reference	PA
Altitude	msl bound lower : 6000 msl bound upper : 6000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : pit
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	cruise other descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Flight Phase	cruise other descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : approach
Qualification	controller : radar
Experience	controller radar : 14
ASRS Report	198363
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation
Independent Detector	other other : unspecified atc
Resolutory Action	controller : issued new clearance other
Consequence	faa : investigated
Miss Distance	horizontal : 9000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

During a busy arrival push, controller vectoring several aircraft to ILS 32. Air carrier X was on downwind at 6000 ft and commuter Y was straight in on ILS at 6000 ft, slowed to 170 KTS. X was given turn north for final and not descended. Controller anticipated a reasonable turn. To be honest there was no doubt in my mind that separation would be maintained. Another aircraft checked in on frequency at this time, diverted my attention, because it was an unusual altitude, reported in at, and before I got back to my final, air carrier X and aircraft Y were on converging courses and I had to turn aircraft Y off localizer and descend aircraft.

Original NASA ASRS Text

Title: LTSS BTWN ACR AND COMMUTER. OPERROR.

Narrative: DURING A BUSY ARR PUSH, CTLR VECTORING SEVERAL ACFT TO ILS 32. ACR X WAS ON DOWNWIND AT 6000 FT AND COMMUTER Y WAS STRAIGHT IN ON ILS AT 6000 FT, SLOWED TO 170 KTS. X WAS GIVEN TURN N FOR FINAL AND NOT DSNDED. CTLR ANTICIPATED A REASONABLE TURN. TO BE HONEST THERE WAS NO DOUBT IN MY MIND THAT SEPARATION WOULD BE MAINTAINED. ANOTHER ACFT CHKED IN ON FREQ AT THIS TIME, DIVERTED MY ATTN, BECAUSE IT WAS AN UNUSUAL ALT, RPTED IN AT, AND BEFORE I GOT BACK TO MY FINAL, ACR X AND ACFT Y WERE ON CONVERGING COURSES AND I HAD TO TURN ACFT Y OFF LOC AND DSND ACFT.

Data retrieved from NASA's ASRS site as of July 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.