BA3100 crew avoids near midair collision with lear jet thanks to TCASII.

Attributes
ACN	434682
Time
Date	199904
Day	Sun
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : sli.vortac
State Reference	CA
Altitude	msl bound lower : 15400 msl bound upper : 16000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla.artcc
Operator	common carrier : air carrier
Make Model Name	Jetstream 31
Operating Under FAR Part	Part 121
Navigation In Use	other vortac
Flight Phase	climbout : intermediate altitude
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zla.artcc
Operator	general aviation : corporate
Make Model Name	Gates Learjet Corp Undifferentiated or Other Model
Operating Under FAR Part	Part 91
Flight Phase	climbout : intermediate altitude
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time total : 4900
ASRS Report	434682
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : multi engine pilot : commercial
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : nmac non adherence : required legal separation
Independent Detector	aircraft equipment : tcas other flight crewa other flight crewb
Resolutory Action	flight crew : took evasive action flight crew : returned to assigned airspace
Miss Distance	horizontal : 400 vertical : 200
Supplementary
Problem Areas	Airspace Structure ATC Human Performance Flight Crew Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

While climbing through 15500 ft, I noticed proximity traffic at our 6 O'clock and 5 NM (on TCASII). TCASII was set to 12 NM range and 'above' for the climb. The traffic was 600 ft lower and climbing. As we reached 16000 ft, I asked ATC about the target. As ATC responded 'no observed traffic,' the TCASII issued an RA to descend at 800-1000 FPM. The copilot pitched down, complying with the RA and I notified ATC we were following an RA and that we had traffic in sight 200 ft above us. It was a lear jet at approximately 16000 ft off our right side. We had descended out of 16000 ft and saw him. ATC then issued a traffic call for 'faster moving traffic' at our 1 O'clock. As we passed through 15500 ft, the TCASII announced 'clear of conflict.' we leveled at 15400 ft and initiated a climb back to 16000 ft while notifying ATC. The lear jet leveled at 16500 ft, and checked in with ATC. In my estimation we would have either collided with this lear jet or missed by 20 ft had we not descended on the RA. At fault was the lear jet overtaking us and not complying with the see and avoid requirement. Visibility was at least 60 NM and there were no clouds. ATC's failure to monitor and notify us of proximity targets contributed to the situation. I do not feel my crew could have possibly done anything different. The lear jet was behind us, overtaking us, not talking to anyone, we picked him up 5 NM behind us, we followed and complied with all procedures and regulations.

Original NASA ASRS Text

Title: BA3100 CREW AVOIDS NMAC WITH LEAR JET THANKS TO TCASII.

Narrative: WHILE CLBING THROUGH 15500 FT, I NOTICED PROX TFC AT OUR 6 O'CLOCK AND 5 NM (ON TCASII). TCASII WAS SET TO 12 NM RANGE AND 'ABOVE' FOR THE CLB. THE TFC WAS 600 FT LOWER AND CLBING. AS WE REACHED 16000 FT, I ASKED ATC ABOUT THE TARGET. AS ATC RESPONDED 'NO OBSERVED TFC,' THE TCASII ISSUED AN RA TO DSND AT 800-1000 FPM. THE COPLT PITCHED DOWN, COMPLYING WITH THE RA AND I NOTIFIED ATC WE WERE FOLLOWING AN RA AND THAT WE HAD TFC IN SIGHT 200 FT ABOVE US. IT WAS A LEAR JET AT APPROX 16000 FT OFF OUR R SIDE. WE HAD DSNDED OUT OF 16000 FT AND SAW HIM. ATC THEN ISSUED A TFC CALL FOR 'FASTER MOVING TFC' AT OUR 1 O'CLOCK. AS WE PASSED THROUGH 15500 FT, THE TCASII ANNOUNCED 'CLR OF CONFLICT.' WE LEVELED AT 15400 FT AND INITIATED A CLB BACK TO 16000 FT WHILE NOTIFYING ATC. THE LEAR JET LEVELED AT 16500 FT, AND CHKED IN WITH ATC. IN MY ESTIMATION WE WOULD HAVE EITHER COLLIDED WITH THIS LEAR JET OR MISSED BY 20 FT HAD WE NOT DSNDED ON THE RA. AT FAULT WAS THE LEAR JET OVERTAKING US AND NOT COMPLYING WITH THE SEE AND AVOID REQUIREMENT. VISIBILITY WAS AT LEAST 60 NM AND THERE WERE NO CLOUDS. ATC'S FAILURE TO MONITOR AND NOTIFY US OF PROX TARGETS CONTRIBUTED TO THE SIT. I DO NOT FEEL MY CREW COULD HAVE POSSIBLY DONE ANYTHING DIFFERENT. THE LEAR JET WAS BEHIND US, OVERTAKING US, NOT TALKING TO ANYONE, WE PICKED HIM UP 5 NM BEHIND US, WE FOLLOWED AND COMPLIED WITH ALL PROCS AND REGS.

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.