MD80 flight crew has a TCAS RA while on vector to ILS runway 19R sna.

Attributes
ACN	696089
Time
Date	200605
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : sli.vortac
State Reference	CA
Altitude	msl single value : 5000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sct.tracon
Operator	common carrier : air carrier
Make Model Name	MD-80 Series (DC-9-80) Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	ils localizer only : 19r
Flight Phase	descent : approach
Route In Use	enroute : on vectors
Flight Plan	IFR
Aircraft 2
Controlling Facilities	tracon : sct.tracon
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Flight Plan	VFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
ASRS Report	767089
Person 2
Function	flight crew : captain oversight : pic
Events
Anomaly	altitude deviation : excursion from assigned altitude conflict : airborne critical non adherence : clearance
Independent Detector	aircraft equipment : tcas other flight crewa
Resolutory Action	controller : issued advisory flight crew : took evasive action flight crew : returned to assigned altitude
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance Aircraft Airspace Structure
Primary Problem	Flight Crew Human Performance

Narrative:

While level at 5000 ft MSL on radar vectors to ILS runway 19R at sna; we received a call from ATC (socal approach) about VFR traffic at 10 O'clock position high. We did not see the traffic. TCAS showed him 400 ft above us. We got a TCAS RA and descended as directed by the RA to 4550 ft MSL. When clear of conflict we returned to our assigned 5000 ft MSL. Called socal. Spoke with supervisor about congested airspace. ATC said he saw us as having handled the event correctly; but would file a report due to inadequate aircraft separation. FAA air carrier inspector was in the cockpit jumpseat.

Original NASA ASRS Text

Title: MD80 FLT CREW HAS A TCAS RA WHILE ON VECTOR TO ILS RWY 19R SNA.

Narrative: WHILE LEVEL AT 5000 FT MSL ON RADAR VECTORS TO ILS RWY 19R AT SNA; WE RECEIVED A CALL FROM ATC (SOCAL APCH) ABOUT VFR TFC AT 10 O'CLOCK POS HIGH. WE DID NOT SEE THE TFC. TCAS SHOWED HIM 400 FT ABOVE US. WE GOT A TCAS RA AND DSNDED AS DIRECTED BY THE RA TO 4550 FT MSL. WHEN CLR OF CONFLICT WE RETURNED TO OUR ASSIGNED 5000 FT MSL. CALLED SOCAL. SPOKE WITH SUPVR ABOUT CONGESTED AIRSPACE. ATC SAID HE SAW US AS HAVING HANDLED THE EVENT CORRECTLY; BUT WOULD FILE A RPT DUE TO INADEQUATE ACFT SEPARATION. FAA ACR INSPECTOR WAS IN THE COCKPIT JUMPSEAT.

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.