Potential conflict.

Attributes
ACN	292529
Time
Date	199412
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : pxn
State Reference	CA
Altitude	msl bound lower : 33500 msl bound upper : 35000
Environment
Flight Conditions	VMC
Light	Dusk
Aircraft 1
Controlling Facilities	artcc : zoa tower : iad
Operator	common carrier : air carrier
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent other
Route In Use	arrival other arrival star : star enroute : on vectors
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	DC-9 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	cruise other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : flight engineer pilot : commercial pilot : atp
Experience	flight time last 90 days : 210 flight time total : 15000 flight time type : 3500
ASRS Report	292529
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation other anomaly other
Independent Detector	aircraft equipment other aircraft equipment : unspecified other controllera
Resolutory Action	controller : issued new clearance flight crew : took evasive action other
Consequence	Other
Miss Distance	horizontal : 12000 vertical : 500
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

On a scheduled flight at FL350 from lax-oak we were experiencing chop at FL350 and requested a descent to FL310. Our position was on the pxn 1 arrival (gorman txn) approximately 45 mi southeast of pxn. We were cleared by center to descend to FL310. After commencing descent, passing approximately FL340 we were told to 'turn 40 degrees right immediately and maintain FL350.' TCASII showed a target at 12 O'clock, level FL330. Continued hard right turn and initiated climb. During this maneuver we received a 'climb' RA. Conflicting traffic acquired visually and separation was assured. Leveled at FL350 on divergent heading from conflict traffic. Later cleared direct pxn and to descend to FL310. Flight proceeded without further incident. Supplemental information from acn 292545: ATC cleared us to descend from FL350 to FL310. Passing FL336, ATC informed us to turn right 40 degrees for traffic and climb immediately back to FL350. As we started our climbing right turn, the TCASII gave a 'climb RA.' we had the sbound dc-9 traffic in sight as it passed 5 mi west of our position.

Original NASA ASRS Text

Title: POTENTIAL CONFLICT.

Narrative: ON A SCHEDULED FLT AT FL350 FROM LAX-OAK WE WERE EXPERIENCING CHOP AT FL350 AND REQUESTED A DSCNT TO FL310. OUR POS WAS ON THE PXN 1 ARR (GORMAN TXN) APPROX 45 MI SE OF PXN. WE WERE CLRED BY CTR TO DSND TO FL310. AFTER COMMENCING DSCNT, PASSING APPROX FL340 WE WERE TOLD TO 'TURN 40 DEGS R IMMEDIATELY AND MAINTAIN FL350.' TCASII SHOWED A TARGET AT 12 O'CLOCK, LEVEL FL330. CONTINUED HARD R TURN AND INITIATED CLB. DURING THIS MANEUVER WE RECEIVED A 'CLB' RA. CONFLICTING TFC ACQUIRED VISUALLY AND SEPARATION WAS ASSURED. LEVELED AT FL350 ON DIVERGENT HDG FROM CONFLICT TFC. LATER CLRED DIRECT PXN AND TO DSND TO FL310. FLT PROCEEDED WITHOUT FURTHER INCIDENT. SUPPLEMENTAL INFO FROM ACN 292545: ATC CLRED US TO DSND FROM FL350 TO FL310. PASSING FL336, ATC INFORMED US TO TURN R 40 DEGS FOR TFC AND CLB IMMEDIATELY BACK TO FL350. AS WE STARTED OUR CLBING R TURN, THE TCASII GAVE A 'CLB RA.' WE HAD THE SBOUND DC-9 TFC IN SIGHT AS IT PASSED 5 MI W OF OUR POS.

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.