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|
Attributes | |
ACN | 685325 |
Time | |
Date | 200601 |
Place | |
Locale Reference | atc facility : zla.artcc |
State Reference | CA |
Altitude | msl single value : 25000 |
Environment | |
Flight Conditions | VMC |
Light | Daylight |
Aircraft 1 | |
Controlling Facilities | artcc : zla.artcc |
Operator | common carrier : air carrier |
Make Model Name | B737-700 |
Operating Under FAR Part | Part 121 |
Navigation In Use | other vortac |
Flight Phase | climbout : intermediate altitude |
Route In Use | departure sid : gorman4 |
Flight Plan | IFR |
Aircraft 2 | |
Controlling Facilities | artcc : zla.artcc |
Operator | common carrier : air carrier |
Make Model Name | Regional Jet CL65 Undifferentiated or Other Model |
Operating Under FAR Part | Part 121 |
Flight Phase | cruise : level |
Flight Plan | IFR |
Person 1 | |
Affiliation | company : air carrier |
Function | flight crew : first officer |
Experience | flight time last 90 days : 140 flight time total : 4000 flight time type : 1850 |
ASRS Report | 685325 |
Person 2 | |
Affiliation | company : air carrier |
Function | flight crew : captain oversight : pic |
Experience | flight time last 90 days : 180 flight time total : 15000 flight time type : 11000 |
ASRS Report | 685326 |
Events | |
Anomaly | conflict : airborne critical |
Independent Detector | aircraft equipment : tcas other flight crewa other flight crewb |
Resolutory Action | flight crew : took evasive action |
Consequence | faa : investigated faa : reviewed incident with flight crew |
Miss Distance | vertical : 1000 |
Supplementary | |
Problem Areas | ATC Human Performance |
Primary Problem | ATC Human Performance |
Narrative:
During step climb to FL340; we were vectored slightly off the gorman departure and then given on course to gmn by ZLA. We were assigned FL250; leveled off; and were told of traffic at 10 O'clock position at FL250 and 8 mi. While searching for the traffic on a 310 degree heading; we received a TCAS TA quickly followed by an RA. I was the PF (first officer); so I immediately disengaged the autoplt and followed the TCAS guidance to climb while looking ahead for the intruder traffic now at 12 O'clock position. The captain and I initially picked up the traffic visually approximately 3 mi away and crossed over the top of the other carrier rj by approximately 1000 ft. The traffic was heading approximately 090-100 degrees at FL250. During the avoidance climb; I believe the controller discovered the conflict and began to reissue altitude assignments; but because of the TCAS RA audio to 'adjust vertical speed' and 2 jumpseaters telling me to climb and pointing out the traffic; I couldn't understand the controller's call. At this point though; his instruction was meaningless as the aircraft were about to merge. I believe the controller erred in assigning both aircraft the same altitude; although I'm not sure why this occurred (distraction; loss of situational awareness...). Further review of the ATC tapes showed 5 mi of lateral separation while both aircraft were at FL250; and 1100 ft of vertical separation at the merge point.
Original NASA ASRS Text
Title: B737 FLT CREW WITH ZLA AT FL250 DESCRIBED CONFLICT WITH OPPOSITE DIRECTION TFC AND RESPONDED TO TCAS RA PREVENTING A LOSS OF LEGAL SEPARATION.
Narrative: DURING STEP CLB TO FL340; WE WERE VECTORED SLIGHTLY OFF THE GORMAN DEP AND THEN GIVEN ON COURSE TO GMN BY ZLA. WE WERE ASSIGNED FL250; LEVELED OFF; AND WERE TOLD OF TFC AT 10 O'CLOCK POS AT FL250 AND 8 MI. WHILE SEARCHING FOR THE TFC ON A 310 DEG HDG; WE RECEIVED A TCAS TA QUICKLY FOLLOWED BY AN RA. I WAS THE PF (FO); SO I IMMEDIATELY DISENGAGED THE AUTOPLT AND FOLLOWED THE TCAS GUIDANCE TO CLB WHILE LOOKING AHEAD FOR THE INTRUDER TFC NOW AT 12 O'CLOCK POS. THE CAPT AND I INITIALLY PICKED UP THE TFC VISUALLY APPROX 3 MI AWAY AND CROSSED OVER THE TOP OF THE OTHER CARRIER RJ BY APPROX 1000 FT. THE TFC WAS HDG APPROX 090-100 DEGS AT FL250. DURING THE AVOIDANCE CLB; I BELIEVE THE CTLR DISCOVERED THE CONFLICT AND BEGAN TO REISSUE ALT ASSIGNMENTS; BUT BECAUSE OF THE TCAS RA AUDIO TO 'ADJUST VERT SPD' AND 2 JUMPSEATERS TELLING ME TO CLB AND POINTING OUT THE TFC; I COULDN'T UNDERSTAND THE CTLR'S CALL. AT THIS POINT THOUGH; HIS INSTRUCTION WAS MEANINGLESS AS THE ACFT WERE ABOUT TO MERGE. I BELIEVE THE CTLR ERRED IN ASSIGNING BOTH ACFT THE SAME ALT; ALTHOUGH I'M NOT SURE WHY THIS OCCURRED (DISTR; LOSS OF SITUATIONAL AWARENESS...). FURTHER REVIEW OF THE ATC TAPES SHOWED 5 MI OF LATERAL SEPARATION WHILE BOTH ACFT WERE AT FL250; AND 1100 FT OF VERT SEPARATION AT THE MERGE POINT.
Data retrieved from NASA's ASRS site as of January 2009 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.