Air carrier X had less than standard separation from air carrier Y. System error.

Attributes
ACN	177036
Time
Date	199104
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : syr
State Reference	NY
Altitude	msl bound lower : 19300 msl bound upper : 20000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob tower : pbi
Operator	common carrier : air carrier
Make Model Name	Small Transport, Low Wing, 2 Turboprop Eng
Flight Phase	descent other
Route In Use	enroute : direct
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	enroute : direct
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller radar : 24
ASRS Report	177036
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : published procedure non adherence : required legal separation
Independent Detector	atc equipment other atc equipment : unspecified
Resolutory Action	none taken : detected after the fact
Consequence	faa : investigated
Miss Distance	horizontal : 19200 vertical : 700
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Air carrier X and air carrier Y both inbound to roc. Were over syr at FL200 and FL210. Airspace was compressed because of military use of R5203. Departure off syr compounded problem. Short period of time to get 2 inbnds down. Departure was turned left, climb to 13000'. Air carrier X given 10 degree right turn and descent to 14000'. Air carrier Y was given descent clearance to FL190 when air carrier X thought to be leaving FL190. Air carrier Y much faster rate of descent and apparently air carrier X was only leaving FL193 when air carrier Y given descent clearance. If this was case, poor judgement on my part. Air carrier X was small transport.

Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION FROM ACR Y. SYSTEM ERROR.

Narrative: ACR X AND ACR Y BOTH INBND TO ROC. WERE OVER SYR AT FL200 AND FL210. AIRSPACE WAS COMPRESSED BECAUSE OF MIL USE OF R5203. DEP OFF SYR COMPOUNDED PROB. SHORT PERIOD OF TIME TO GET 2 INBNDS DOWN. DEP WAS TURNED LEFT, CLB TO 13000'. ACR X GIVEN 10 DEG RIGHT TURN AND DSNT TO 14000'. ACR Y WAS GIVEN DSNT CLRNC TO FL190 WHEN ACR X THOUGHT TO BE LEAVING FL190. ACR Y MUCH FASTER RATE OF DSNT AND APPARENTLY ACR X WAS ONLY LEAVING FL193 WHEN ACR Y GIVEN DSNT CLRNC. IF THIS WAS CASE, POOR JUDGEMENT ON MY PART. ACR X WAS SMT.

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.