Flight crew of B767-300 experience TCASII TA and subsequent dual RA commands on sadde arrival to lax...

Attributes
ACN	614435
Time
Date	200404
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : smo.airport
State Reference	CA
Altitude	msl single value : 9000
Aircraft 1
Controlling Facilities	tracon : sct.tracon tower : sfo.tower
Operator	common carrier : air carrier
Make Model Name	B767-300 and 300 ER
Operating Under FAR Part	Part 121
Flight Phase	cruise : level descent : intermediate altitude
Route In Use	arrival star : sadde
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : sct.tracon
Operator	common carrier : air carrier
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	descent : intermediate altitude
Flight Plan	IFR
Person 1
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	614435
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	conflict : airborne critical
Independent Detector	aircraft equipment : tcas other controllera
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Supplementary
Problem Areas	Airspace Structure ATC Human Performance Flight Crew Human Performance
Primary Problem	Ambiguous

Narrative:

On sadde 6 arrival, cleared to smo, cleared to descend from 10000 ft to 7000 ft. Then instructed to turn right, heading 110 degrees to avoid VFR traffic. VFR traffic not showing on TCASII. Had been following fairly close behind air carrier B737. Towards completion of turn, and at approximately 9000 ft, we received a TA followed almost immediately by 'climb' RA, followed immediately by a 'descend now' RA. Initial TA thought to be the B737. Executed RA's and reported them to socal approach. Approach indicated RA had been caused by a beechcraft of which we were now clear. Neither pilot nor the observer ever saw the beechcraft. Rest of approach and landing runway 24R uneventful. This incident deserves to be investigated. Given the rapidity of the TA and the RA's, and both the climb and descend RA's, I would be particularly interested where that beechcraft was relative to our aircraft. We may have had a near miss. Everyone ready for rvsm?

Original NASA ASRS Text

Title: FLT CREW OF B767-300 EXPERIENCE TCASII TA AND SUBSEQUENT DUAL RA COMMANDS ON SADDE ARR TO LAX.

Narrative: ON SADDE 6 ARR, CLRED TO SMO, CLRED TO DSND FROM 10000 FT TO 7000 FT. THEN INSTRUCTED TO TURN R, HDG 110 DEGS TO AVOID VFR TFC. VFR TFC NOT SHOWING ON TCASII. HAD BEEN FOLLOWING FAIRLY CLOSE BEHIND ACR B737. TOWARDS COMPLETION OF TURN, AND AT APPROX 9000 FT, WE RECEIVED A TA FOLLOWED ALMOST IMMEDIATELY BY 'CLB' RA, FOLLOWED IMMEDIATELY BY A 'DSND NOW' RA. INITIAL TA THOUGHT TO BE THE B737. EXECUTED RA'S AND RPTED THEM TO SOCAL APCH. APCH INDICATED RA HAD BEEN CAUSED BY A BEECHCRAFT OF WHICH WE WERE NOW CLR. NEITHER PLT NOR THE OBSERVER EVER SAW THE BEECHCRAFT. REST OF APCH AND LNDG RWY 24R UNEVENTFUL. THIS INCIDENT DESERVES TO BE INVESTIGATED. GIVEN THE RAPIDITY OF THE TA AND THE RA'S, AND BOTH THE CLB AND DSND RA'S, I WOULD BE PARTICULARLY INTERESTED WHERE THAT BEECHCRAFT WAS RELATIVE TO OUR ACFT. WE MAY HAVE HAD A NEAR MISS. EVERYONE READY FOR RVSM?

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.