Air carrier was descended through an altitude occupied by another aircraft.

Attributes
ACN	123279
Time
Date	198909
Day	Sun
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : alb
State Reference	NY
Altitude	msl bound lower : 33400 msl bound upper : 35000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zbw
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	descent other
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
ASRS Report	123279
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	non adherence : published procedure non adherence : required legal separation
Independent Detector	atc equipment other atc equipment : unspecified other controllera
Resolutory Action	controller : issued new clearance
Consequence	Other
Miss Distance	horizontal : 28800 vertical : 1600
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Air carrier Y inbound to bos descending from FL370 to FL310 descended thru FL350 within 5 NM of wbound air carrier Y, both aircraft were issued radar vectors to avoid each other and loss of vertical separation occurred at FL350 and FL354 descending and 4.8 NM over alb, ny.

Original NASA ASRS Text

Title: ACR WAS DESCENDED THROUGH AN ALT OCCUPIED BY ANOTHER ACFT.

Narrative: ACR Y INBND TO BOS DESCENDING FROM FL370 TO FL310 DESCENDED THRU FL350 WITHIN 5 NM OF WBOUND ACR Y, BOTH ACFT WERE ISSUED RADAR VECTORS TO AVOID EACH OTHER AND LOSS OF VERTICAL SEPARATION OCCURRED AT FL350 AND FL354 DESCENDING AND 4.8 NM OVER ALB, NY.

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.