A320 flight crew act on TCASII RA as ZLA amends descent clearance.

Attributes
ACN	523637
Time
Date	200108
Day	Mon
Local Time Of Day	1201 To 1800
Place
Locale Reference	navaid : bty.vortac
State Reference	NV
Altitude	msl single value : 26500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla.artcc tower : ict.tower
Operator	common carrier : air carrier
Make Model Name	A320
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : vacating altitude
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zla.artcc
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Flight Phase	cruise : level
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 250 flight time total : 16000 flight time type : 8000
ASRS Report	523637
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	conflict : airborne critical non adherence : published procedure non adherence : required legal separation
Independent Detector	atc equipment other atc equipment : radar aircraft equipment : tcas other controllera other flight crewa
Resolutory Action	controller : issued new clearance flight crew : took evasive action
Miss Distance	vertical : 400
Supplementary
Problem Areas	ATC Human Performance
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

We were given a descent clearance pilot discretion to FL240. Shortly after leaving FL270, we were told to return to FL270 and our TCASII RA alert 'climb' went off. There was an aircraft at our 11:30-12 O'clock position, 400 ft. We complied with the RA (TCASII worked excellent).

Original NASA ASRS Text

Title: A320 FLC ACT ON TCASII RA AS ZLA AMENDS DSCNT CLRNC.

Narrative: WE WERE GIVEN A DSCNT CLRNC PLT DISCRETION TO FL240. SHORTLY AFTER LEAVING FL270, WE WERE TOLD TO RETURN TO FL270 AND OUR TCASII RA ALERT 'CLB' WENT OFF. THERE WAS AN ACFT AT OUR 11:30-12 O'CLOCK POS, 400 FT. WE COMPLIED WITH THE RA (TCASII WORKED EXCELLENT).

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.