Controller failed to provide standard separation between 2 aircraft under his control.

Attributes
ACN	146732
Time
Date	199005
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : har
State Reference	PA
Altitude	msl bound lower : 18000 msl bound upper : 18000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zny
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 4 Turbojet Eng
Navigation In Use	Other
Flight Phase	cruise other
Route In Use	enroute airway : j220
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	descent other
Route In Use	arrival other enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 2
ASRS Report	146732
Person 2
Affiliation	government : faa
Function	controller : radar
Qualification	controller : developmental
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 21000 vertical : 0
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Widebody transport northbound J220 level at FL180. Medium large transport southbound descending to FL180. Medium large transport was west of J220. Handoff person was coordinating a 200 degree heading with the sector handing off medium large transport to my sector. This heading would have kept medium large transport well clear of widebody transport to the west. The data block showed widebody transport climbing to FL310. Medium large transport checked on the frequency descending to FL180, heading southbound on a 200 degree heading. Medium large transport began a left turn descending out of FL187 for FL180 heading east. I instructed medium large transport to turn right to a 250 degree heading. When medium large transport questioned the right turn I instructed medium large transport to fly the 250 degree heading. As medium large transport turned right I gave traffic at 12 O'clock, 4 mi at FL180 (widebody transport). Medium large transport informed me that he had the traffic in sight. Medium large transport was also cleared to 150. Widebody transport was also instructed to climb to FL240. Medium large transport's flight plan was psb psb 151 shilo V93 back dca. I heard my handoff person say, 'I'll take him (medium large transport) on that 200 degree heading.' although I did not ask the pilot what his last route clearance was, medium large transport was apparently on a 200 degree heading to join the psb 151 degree right. When medium large transport turned left medium large transport was in conflict with widebody transport. There were 2 trnees at my radar sector. I was allowing the radar trnee to make all the decisions himself. Widebody transport was climbing to FL210 into my sector. An light transport was westbound leaving 15000' for FL240. The trnee stopped the widebody transport at FL180 allowing the light transport to continue climb. Widebody transport now could have been cleared to FL190 at this time since the light transport was leaving FL200 for FL240. I was attempting to allow the trnee to make all the decisions and did not interfere. Had widebody transport been climbing, when medium large transport made the left turn there would not have been a loss of sep. My handoff person and I thought that medium large transport was assigned a 200 degree and not informed that medium large transport was to join the psb 151 degree right. The sector handing off medium large transport to me had radar contact on widebody transport with a data block showing widebody transport climbing to FL310.

Original NASA ASRS Text

Title: CTLR FAILED TO PROVIDE STANDARD SEPARATION BETWEEN 2 ACFT UNDER HIS CONTROL.

Narrative: WDB NBND J220 LEVEL AT FL180. MLG SBND DSNDING TO FL180. MLG WAS W OF J220. HDOF PERSON WAS COORDINATING A 200 DEG HDG WITH THE SECTOR HANDING OFF MLG TO MY SECTOR. THIS HDG WOULD HAVE KEPT MLG WELL CLR OF WDB TO THE W. THE DATA BLOCK SHOWED WDB CLBING TO FL310. MLG CHKED ON THE FREQ DSNDING TO FL180, HDG SBND ON A 200 DEG HDG. MLG BEGAN A LEFT TURN DSNDING OUT OF FL187 FOR FL180 HDG E. I INSTRUCTED MLG TO TURN RIGHT TO A 250 DEG HDG. WHEN MLG QUESTIONED THE RIGHT TURN I INSTRUCTED MLG TO FLY THE 250 DEG HDG. AS MLG TURNED RIGHT I GAVE TFC AT 12 O'CLOCK, 4 MI AT FL180 (WDB). MLG INFORMED ME THAT HE HAD THE TFC IN SIGHT. MLG WAS ALSO CLRED TO 150. WDB WAS ALSO INSTRUCTED TO CLB TO FL240. MLG'S FLT PLAN WAS PSB PSB 151 SHILO V93 BACK DCA. I HEARD MY HDOF PERSON SAY, 'I'LL TAKE HIM (MLG) ON THAT 200 DEG HDG.' ALTHOUGH I DID NOT ASK THE PLT WHAT HIS LAST RTE CLRNC WAS, MLG WAS APPARENTLY ON A 200 DEG HDG TO JOIN THE PSB 151 DEG R. WHEN MLG TURNED LEFT MLG WAS IN CONFLICT WITH WDB. THERE WERE 2 TRNEES AT MY RADAR SECTOR. I WAS ALLOWING THE RADAR TRNEE TO MAKE ALL THE DECISIONS HIMSELF. WDB WAS CLBING TO FL210 INTO MY SECTOR. AN LTT WAS WBND LEAVING 15000' FOR FL240. THE TRNEE STOPPED THE WDB AT FL180 ALLOWING THE LTT TO CONTINUE CLB. WDB NOW COULD HAVE BEEN CLRED TO FL190 AT THIS TIME SINCE THE LTT WAS LEAVING FL200 FOR FL240. I WAS ATTEMPTING TO ALLOW THE TRNEE TO MAKE ALL THE DECISIONS AND DID NOT INTERFERE. HAD WDB BEEN CLBING, WHEN MLG MADE THE LEFT TURN THERE WOULD NOT HAVE BEEN A LOSS OF SEP. MY HDOF PERSON AND I THOUGHT THAT MLG WAS ASSIGNED A 200 DEG AND NOT INFORMED THAT MLG WAS TO JOIN THE PSB 151 DEG R. THE SECTOR HANDING OFF MLG TO ME HAD RADAR CONTACT ON WDB WITH A DATA BLOCK SHOWING WDB CLBING TO FL310.

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.