B737-200 has TCASII RA on approach.

Attributes
ACN	315674
Time
Date	199509
Day	Sun
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : ldn
State Reference	VA
Altitude	msl bound lower : 9000 msl bound upper : 10000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : iad
Operator	common carrier : air carrier
Make Model Name	B737-200
Operating Under FAR Part	Part 121
Flight Phase	descent other
Route In Use	arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 160 flight time total : 8900 flight time type : 1400
ASRS Report	315674
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other flight crewa
Resolutory Action	flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 300
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

Our flight, a B737-200 from iah to iad, was issued a heading of 060 degrees to intercept the 'jassen 1' arrival to dulles. Our position at this point was approximately 43 NM southwest of aml on the aml 259 degree radial. We were still west of doccs intersection and west of the 206 degree radial off ldn. Turning to intercept the 206 degree radial off aml, we received an 'RA' to climb. Our conflicting traffic was approximately 11 O'clock and 300 ft below at approximately 1 mi. We climbed from our assigned altitude of 9000 ft to 10000 ft and notified dulles approach of the deviation. We were then issued a descent to 5000 ft and a right turn to 080 degrees to intercept the 'jassen 1' arrival west of aml (300 degree radial). The crew's post flight discussion concluded that ATC should have been clrer on where they wanted us to intercept the arrival (ie: 060 degree heading to intercept aml 300 degree radial jassen arrival). My actions from now on will be more inquiry into specifics of what radial/bearing to intercept from an ATC issued heading -- especially on stars or sids.

Original NASA ASRS Text

Title: B737-200 HAS TCASII RA ON APCH.

Narrative: OUR FLT, A B737-200 FROM IAH TO IAD, WAS ISSUED A HDG OF 060 DEGS TO INTERCEPT THE 'JASSEN 1' ARR TO DULLES. OUR POS AT THIS POINT WAS APPROX 43 NM SW OF AML ON THE AML 259 DEG RADIAL. WE WERE STILL W OF DOCCS INTXN AND W OF THE 206 DEG RADIAL OFF LDN. TURNING TO INTERCEPT THE 206 DEG RADIAL OFF AML, WE RECEIVED AN 'RA' TO CLB. OUR CONFLICTING TFC WAS APPROX 11 O'CLOCK AND 300 FT BELOW AT APPROX 1 MI. WE CLBED FROM OUR ASSIGNED ALT OF 9000 FT TO 10000 FT AND NOTIFIED DULLES APCH OF THE DEV. WE WERE THEN ISSUED A DSCNT TO 5000 FT AND A R TURN TO 080 DEGS TO INTERCEPT THE 'JASSEN 1' ARR W OF AML (300 DEG RADIAL). THE CREW'S POST FLT DISCUSSION CONCLUDED THAT ATC SHOULD HAVE BEEN CLRER ON WHERE THEY WANTED US TO INTERCEPT THE ARR (IE: 060 DEG HDG TO INTERCEPT AML 300 DEG RADIAL JASSEN ARR). MY ACTIONS FROM NOW ON WILL BE MORE INQUIRY INTO SPECIFICS OF WHAT RADIAL/BEARING TO INTERCEPT FROM AN ATC ISSUED HDG -- ESPECIALLY ON STARS OR SIDS.

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.