Air carrier large transport flight crew receives TCAS RA while in descent to dca.

Attributes
ACN	181591
Time
Date	199106
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : esl airport : dca
State Reference	WV
Altitude	msl bound lower : 16500 msl bound upper : 17000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	descent other
Route In Use	arrival other arrival star : star enroute airway : zdc
Flight Plan	IFR
Aircraft 2
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise other
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 225 flight time total : 15000 flight time type : 10000
ASRS Report	181591
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	conflict : airborne less severe
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	controller : issued new clearance other
Consequence	Other
Miss Distance	horizontal : 0 vertical : 500
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Descending on bucko arrival to dca with clearance to cross druzz at 15000'. We were 12-15 NM west of druzz at approximately 19000' descending. We received from ATC VFR traffic 12 O'clock, 16500'. We did not hear the distance. We had no visibility on the traffic, but a few seconds later we received a TCAS traffic advisory followed very shortly by an RA to 'reduce descent,' which we did. I notified center and he then issued a clearance to level at 17000', which we did. Seconds later TCAS reported 'clear traffic.' we were then cleared to 15000'.

Original NASA ASRS Text

Title: ACR LGT FLT CREW RECEIVES TCAS RA WHILE IN DESCENT TO DCA.

Narrative: DSNDING ON BUCKO ARR TO DCA WITH CLRNC TO CROSS DRUZZ AT 15000'. WE WERE 12-15 NM W OF DRUZZ AT APPROX 19000' DSNDING. WE RECEIVED FROM ATC VFR TFC 12 O'CLOCK, 16500'. WE DID NOT HEAR THE DISTANCE. WE HAD NO VIS ON THE TFC, BUT A FEW SECS LATER WE RECEIVED A TCAS TFC ADVISORY FOLLOWED VERY SHORTLY BY AN RA TO 'REDUCE DSNT,' WHICH WE DID. I NOTIFIED CENTER AND HE THEN ISSUED A CLRNC TO LEVEL AT 17000', WHICH WE DID. SECS LATER TCAS RPTED 'CLR TFC.' WE WERE THEN CLRED TO 15000'.

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.