LJ55 crew had less than legal separation in ZLA class east airspace.

Attributes
ACN	566961
Time
Date	200211
Day	Wed
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : trm.vortac
State Reference	CA
Altitude	msl single value : 16000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla.artcc
Operator	common carrier : air taxi
Make Model Name	Learjet 55
Operating Under FAR Part	Part 135
Navigation In Use	other
Flight Phase	descent : intermediate altitude
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zla.artcc
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Phase	cruise : level
Person 1
Affiliation	company : air taxi
Function	flight crew : captain oversight : pic
Qualification	pilot : multi engine pilot : atp
Experience	flight time last 90 days : 85 flight time total : 6100 flight time type : 3500
ASRS Report	566961
Person 2
Affiliation	company : air taxi
Function	flight crew : first officer
Events
Anomaly	conflict : airborne critical non adherence : required legal separation non adherence : published procedure non adherence : far other anomaly other
Independent Detector	atc equipment : conflict alert aircraft equipment : tcas other controllera other flight crewa other flight crewb
Resolutory Action	controller : provided flight assist controller : issued new clearance controller : separated traffic flight crew : took evasive action none taken : detected after the fact other
Consequence	faa : reviewed incident with flight crew faa : investigated
Miss Distance	horizontal : 600 vertical : 100
Supplementary
Problem Areas	Flight Crew Human Performance FAA ATC Human Performance Airspace Structure
Primary Problem	Flight Crew Human Performance

Narrative:

As we initiated our descent from 16000 ft MSL, a target appeared on TCASII. It had not been on the screen prior. Simultaneously, ZLA issued a TA, at the same time TCASII issued a 'traffic, traffic' advisory followed immediately by an RA. I initiated an immediate climb to comply with the RA, approximately 1950 FPM climb rate was necessary. I also started a turn (roll) to the left as ATC recommended a 20 degree heading change. We leveled off at 17300 ft MSL. When the RA was resolved, we descended back to 16000 ft MSL and continued our approach to crq without further incident. This near midair collision was later verified by ZLA management after a review of both voice and radar data recordings. Our system had been installed 3 weeks prior to this incident. The system works as advertised. Without it, I may not have been filing this report! I am a believer in TCASII!

Original NASA ASRS Text

Title: LJ55 CREW HAD LESS THAN LEGAL SEPARATION IN ZLA CLASS E AIRSPACE.

Narrative: AS WE INITIATED OUR DSCNT FROM 16000 FT MSL, A TARGET APPEARED ON TCASII. IT HAD NOT BEEN ON THE SCREEN PRIOR. SIMULTANEOUSLY, ZLA ISSUED A TA, AT THE SAME TIME TCASII ISSUED A 'TFC, TFC' ADVISORY FOLLOWED IMMEDIATELY BY AN RA. I INITIATED AN IMMEDIATE CLB TO COMPLY WITH THE RA, APPROX 1950 FPM CLB RATE WAS NECESSARY. I ALSO STARTED A TURN (ROLL) TO THE L AS ATC RECOMMENDED A 20 DEG HDG CHANGE. WE LEVELED OFF AT 17300 FT MSL. WHEN THE RA WAS RESOLVED, WE DSNDED BACK TO 16000 FT MSL AND CONTINUED OUR APCH TO CRQ WITHOUT FURTHER INCIDENT. THIS NMAC WAS LATER VERIFIED BY ZLA MGMNT AFTER A REVIEW OF BOTH VOICE AND RADAR DATA RECORDINGS. OUR SYS HAD BEEN INSTALLED 3 WKS PRIOR TO THIS INCIDENT. THE SYS WORKS AS ADVERTISED. WITHOUT IT, I MAY NOT HAVE BEEN FILING THIS RPT! I AM A BELIEVER IN TCASII!

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.