A B757 descending into lax receives a TCASII RA from an aircraft following. The B757 executes a miss...

Attributes
ACN	403664
Time
Date	199805
Day	Thu
Local Time Of Day	0601 To 1200
Place
Locale Reference	airport : lax
State Reference	CA
Altitude	msl bound lower : 3000 msl bound upper : 3000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : lax
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	approach : visual
Person 1
Affiliation	company : air carrier
Function	oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 13000 flight time type : 1500
ASRS Report	403664
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 : became reoriented flight crew : returned to intended course or assigned course
Consequence	Other
Miss Distance	horizontal : 6000 vertical : 200
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	other

Narrative:

We were cleared a visual approach to runway 24L with a commuter aircraft on final for the runways 25. Approach advised of a commuter off at 3 O'clock on base for runway 24R. We saw him briefly while he was on base leg. With this aircraft behind us now, we got a TA followed by a 'climb, crossing, climb' RA requiring +2000 FPM. Our procedures require compliance with all RA's (exact verbiage follows later). We followed the RA which then put us out of position for a safe, stabilized approach. We overflew the airport and completed the second approach and landing. Aircraft making approachs based on their own visual separation need to understand any maneuvering deemed aggressive by TCASII will result in an RA at higher altitudes. Many companies have no choice in these sits but to comply with the RA. This may even be a boeing limitation in our aircraft operations manual 'compliance with TCASII RA's is required unless the PIC determines that doing so would jeopardize the safe operation of the flight.' technically, our manual allows selection of TA-only mode for closely spaced approachs, but with the updated TCASII software, I have never needed to select it before (the old software was a different story). Callback conversation with reporter revealed the following information: reporter saw an light transport turning in from his right side for runway 24R. He feels confident that this aircraft set off the TCASII RA. If he were to fly the approach again, then he would set his TCASII to 'TA' so he wouldn't have to fly a missed approach in the event an aircraft got close to his aircraft. Although he saw the aircraft come from the right and then turn in behind his aircraft, he is confident that this aircraft produced the TCASII RA. Because he is not absolutely certain this aircraft produced the TCASII RA, he decided to execute a missed approach as instructed by his company policy to always react to a TCASII RA.

Original NASA ASRS Text

Title: A B757 DSNDING INTO LAX RECEIVES A TCASII RA FROM AN ACFT FOLLOWING. THE B757 EXECUTES A MISSED APCH WHEN HIS TCASII INDICATES AN RA. B757 MAKES AN UNEVENTFUL LNDG AFTER EXECUTING HIS MISSED APCH.

Narrative: WE WERE CLRED A VISUAL APCH TO RWY 24L WITH A COMMUTER ACFT ON FINAL FOR THE RWYS 25. APCH ADVISED OF A COMMUTER OFF AT 3 O'CLOCK ON BASE FOR RWY 24R. WE SAW HIM BRIEFLY WHILE HE WAS ON BASE LEG. WITH THIS ACFT BEHIND US NOW, WE GOT A TA FOLLOWED BY A 'CLB, XING, CLB' RA REQUIRING +2000 FPM. OUR PROCS REQUIRE COMPLIANCE WITH ALL RA'S (EXACT VERBIAGE FOLLOWS LATER). WE FOLLOWED THE RA WHICH THEN PUT US OUT OF POS FOR A SAFE, STABILIZED APCH. WE OVERFLEW THE ARPT AND COMPLETED THE SECOND APCH AND LNDG. ACFT MAKING APCHS BASED ON THEIR OWN VISUAL SEPARATION NEED TO UNDERSTAND ANY MANEUVERING DEEMED AGGRESSIVE BY TCASII WILL RESULT IN AN RA AT HIGHER ALTS. MANY COMPANIES HAVE NO CHOICE IN THESE SITS BUT TO COMPLY WITH THE RA. THIS MAY EVEN BE A BOEING LIMITATION IN OUR ACFT OPS MANUAL 'COMPLIANCE WITH TCASII RA'S IS REQUIRED UNLESS THE PIC DETERMINES THAT DOING SO WOULD JEOPARDIZE THE SAFE OP OF THE FLT.' TECHNICALLY, OUR MANUAL ALLOWS SELECTION OF TA-ONLY MODE FOR CLOSELY SPACED APCHS, BUT WITH THE UPDATED TCASII SOFTWARE, I HAVE NEVER NEEDED TO SELECT IT BEFORE (THE OLD SOFTWARE WAS A DIFFERENT STORY). CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR SAW AN LTT TURNING IN FROM HIS R SIDE FOR RWY 24R. HE FEELS CONFIDENT THAT THIS ACFT SET OFF THE TCASII RA. IF HE WERE TO FLY THE APCH AGAIN, THEN HE WOULD SET HIS TCASII TO 'TA' SO HE WOULDN'T HAVE TO FLY A MISSED APCH IN THE EVENT AN ACFT GOT CLOSE TO HIS ACFT. ALTHOUGH HE SAW THE ACFT COME FROM THE R AND THEN TURN IN BEHIND HIS ACFT, HE IS CONFIDENT THAT THIS ACFT PRODUCED THE TCASII RA. BECAUSE HE IS NOT ABSOLUTELY CERTAIN THIS ACFT PRODUCED THE TCASII RA, HE DECIDED TO EXECUTE A MISSED APCH AS INSTRUCTED BY HIS COMPANY POLICY TO ALWAYS REACT TO A TCASII RA.

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.

A B757 descending into lax receives a TCASII RA from an aircraft following. The B757 executes a missed approach when his TCASII indicates an RA. B757 makes an uneventful landing after executing his missed approach.