Near midair collision.

Attributes
ACN	284456
Time
Date	199409
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : smo
State Reference	CA
Altitude	msl bound lower : 5400 msl bound upper : 7000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : lax tower : lax
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	descent : approach descent other
Route In Use	arrival other arrival star : star
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	Jetstream Series Commuter Aircraft
Operating Under FAR Part	Part 135
Navigation In Use	Other Other
Flight Phase	descent : approach descent other
Route In Use	approach : visual
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 100 flight time total : 15500 flight time type : 14000
ASRS Report	284456
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : nmac non adherence : clearance other anomaly other other spatial deviation
Independent Detector	aircraft equipment other aircraft equipment : unspecified
Resolutory Action	flight crew : became reoriented flight crew : returned to intended course or assigned course flight crew : took evasive action
Consequence	Other
Miss Distance	horizontal : 200 vertical : 50
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

Flying level at 7000 ft on sadde STAR to lax we got a TCASII RA to descend. We followed the descend instructions and first officer attempted to inform ATC. Due to congestion on the frequency it took several seconds to break in. We informed ATC of a descent due to TCASII RA. And approach control responded to the effect. No problem, the traffic has you in sight and is maintaining visual separation. RA warning was continuing as we descended through 6000 ft. We could see the red airplane symbol had changed from 0500 ft descending to 0200 descending ft, and we had already descended nearly 1000 ft. It was obvious that the traffic was following us down. We initiated a right turn as we continued descent and told approach that we were still receiving the RA. The controller then cautioned us from continuing descent because we were leaving his airspace. We continued descent and right turn and saw jetstream traffic 200-300 ft left and maybe 50 ft above. ATC then gave us a right turn and we replied that we had traffic in sight just to our left. Controller questioned the jetstream if they had us in sight and they replied they were looking. We continued 120 degree heading, climbed back to 6000 ft from about 5400 ft and were vectored for left traffic runway 25L. My concern is that the controller twice tried to persuade us to stop our descent.

Original NASA ASRS Text

Title: NMAC.

Narrative: FLYING LEVEL AT 7000 FT ON SADDE STAR TO LAX WE GOT A TCASII RA TO DSND. WE FOLLOWED THE DSND INSTRUCTIONS AND FO ATTEMPTED TO INFORM ATC. DUE TO CONGESTION ON THE FREQ IT TOOK SEVERAL SECONDS TO BREAK IN. WE INFORMED ATC OF A DSCNT DUE TO TCASII RA. AND APCH CTL RESPONDED TO THE EFFECT. NO PROB, THE TFC HAS YOU IN SIGHT AND IS MAINTAINING VISUAL SEPARATION. RA WARNING WAS CONTINUING AS WE DSNDED THROUGH 6000 FT. WE COULD SEE THE RED AIRPLANE SYMBOL HAD CHANGED FROM 0500 FT DSNDING TO 0200 DSNDING FT, AND WE HAD ALREADY DSNDED NEARLY 1000 FT. IT WAS OBVIOUS THAT THE TFC WAS FOLLOWING US DOWN. WE INITIATED A R TURN AS WE CONTINUED DSCNT AND TOLD APCH THAT WE WERE STILL RECEIVING THE RA. THE CTLR THEN CAUTIONED US FROM CONTINUING DSCNT BECAUSE WE WERE LEAVING HIS AIRSPACE. WE CONTINUED DSCNT AND R TURN AND SAW JETSTREAM TFC 200-300 FT L AND MAYBE 50 FT ABOVE. ATC THEN GAVE US A R TURN AND WE REPLIED THAT WE HAD TFC IN SIGHT JUST TO OUR L. CTLR QUESTIONED THE JETSTREAM IF THEY HAD US IN SIGHT AND THEY REPLIED THEY WERE LOOKING. WE CONTINUED 120 DEG HDG, CLBED BACK TO 6000 FT FROM ABOUT 5400 FT AND WERE VECTORED FOR L TFC RWY 25L. MY CONCERN IS THAT THE CTLR TWICE TRIED TO PERSUADE US TO STOP OUR DSCNT.

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.