Narrative:

No significant WX, night clear skies. ZLA pointed out traffic at our 9:30 O'clock position at FL270, passing left to right. Seconds later our TCASII sounds 'traffic' alert and it appears at 10:30 O'clock position but only 500 ft below our altitude. The aircraft is sighted, but continues to climb to FL280 as our TCASII indicates zero zero on the altitude differential. The TCASII now shows the aircraft at FL280 and within less than 1 1/2 mi from us. The RA calls out 'climb, climb' as we abruptly turn left and climb (approximately 200 ft) to avoid the aircraft. The aircraft passed within approximately 200 ft below and between 1 1/2 mi laterally to our aircraft. We notify ATC of our required deviation. As the aircraft moved from our 9:30 O'clock position to 12 O'clock position, the controller repeatedly asked to confirm he was at FL270, but with no reply. The sharp left turn and climb to evade caused no injury to crew or passenger, however, a brief description of the cause of the maneuver was given over the PA. Lax ATC was notified and a call to mr X (operations supervisor) was made after landing at lax. He said radar tapes indicated the 2 aircraft passed within 200 ft and 1 1/2 mi, although the radar sweep is only every 12 seconds. I indicated it was much closer and considered it a 'near miss.'

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Original NASA ASRS Text

Title: A POTENTIAL CONFLICT OCCURS BTWN A CLBING DA10 FALCON AND A CRUISING MD80 WHILE IN ZLA AIRSPACE AT FL280. TCASII WAS AN AID IN THE EVASIVE MANEUVER.

Narrative: NO SIGNIFICANT WX, NIGHT CLR SKIES. ZLA POINTED OUT TFC AT OUR 9:30 O'CLOCK POS AT FL270, PASSING L TO R. SECONDS LATER OUR TCASII SOUNDS 'TFC' ALERT AND IT APPEARS AT 10:30 O'CLOCK POS BUT ONLY 500 FT BELOW OUR ALT. THE ACFT IS SIGHTED, BUT CONTINUES TO CLB TO FL280 AS OUR TCASII INDICATES ZERO ZERO ON THE ALT DIFFERENTIAL. THE TCASII NOW SHOWS THE ACFT AT FL280 AND WITHIN LESS THAN 1 1/2 MI FROM US. THE RA CALLS OUT 'CLB, CLB' AS WE ABRUPTLY TURN L AND CLB (APPROX 200 FT) TO AVOID THE ACFT. THE ACFT PASSED WITHIN APPROX 200 FT BELOW AND BTWN 1 1/2 MI LATERALLY TO OUR ACFT. WE NOTIFY ATC OF OUR REQUIRED DEV. AS THE ACFT MOVED FROM OUR 9:30 O'CLOCK POS TO 12 O'CLOCK POS, THE CTLR REPEATEDLY ASKED TO CONFIRM HE WAS AT FL270, BUT WITH NO REPLY. THE SHARP L TURN AND CLB TO EVADE CAUSED NO INJURY TO CREW OR PAX, HOWEVER, A BRIEF DESCRIPTION OF THE CAUSE OF THE MANEUVER WAS GIVEN OVER THE PA. LAX ATC WAS NOTIFIED AND A CALL TO MR X (OPS SUPVR) WAS MADE AFTER LNDG AT LAX. HE SAID RADAR TAPES INDICATED THE 2 ACFT PASSED WITHIN 200 FT AND 1 1/2 MI, ALTHOUGH THE RADAR SWEEP IS ONLY EVERY 12 SECONDS. I INDICATED IT WAS MUCH CLOSER AND CONSIDERED IT A 'NEAR MISS.'

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.