A319 confused descent clearance with heading assignment in ZLA airspace.

Attributes
ACN	600735
Time
Date	200311
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	navaid : hec.vortac
State Reference	CA
Altitude	msl bound lower : 28000 msl bound upper : 31000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla.artcc
Operator	common carrier : air carrier
Make Model Name	A319
Operating Under FAR Part	Part 121
Flight Phase	descent : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : cfi pilot : atp
Experience	flight time last 90 days : 50 flight time total : 8000 flight time type : 600
ASRS Report	600735
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

At the time of the occurrence, the first officer was absent from the cockpit (lavatory) and a company dispatcher was doing a required observation flight. Just before the first officer left, we were given a descent clearance from FL350 to, I think, FL240 and began our descent. I then received a transmission to 'turn right to 280 degrees' and read back 'right to 280' and began the turn. When the first officer returned, I advised him the only change was heading 280 degrees, and he resumed handling the radios. A min or 2 later, ZLA directed us to turn left to 180 degrees and asked what heading we were rolling through. The first officer advised '280 degrees assigned.' ZLA responded by asking if we received a new clearance and said his original call was to 'expedite to 280' meaning FL280. We clarified the altitude and heading and continued the flight. Contributing factors: single pilot in cockpit with no xchk of radio transmission available. Preventive steps: always use full titles of heading and altitude assignments, ie, FL280 or heading 280 degrees. Confusion: expedite to 280 versus turn right to 280. Suggested phraseology: expedite through FL280, maintain FL240.

Original NASA ASRS Text

Title: A319 CONFUSED DSCNT CLRNC WITH HDG ASSIGNMENT IN ZLA AIRSPACE.

Narrative: AT THE TIME OF THE OCCURRENCE, THE FO WAS ABSENT FROM THE COCKPIT (LAVATORY) AND A COMPANY DISPATCHER WAS DOING A REQUIRED OBSERVATION FLT. JUST BEFORE THE FO LEFT, WE WERE GIVEN A DSCNT CLRNC FROM FL350 TO, I THINK, FL240 AND BEGAN OUR DSCNT. I THEN RECEIVED A XMISSION TO 'TURN R TO 280 DEGS' AND READ BACK 'R TO 280' AND BEGAN THE TURN. WHEN THE FO RETURNED, I ADVISED HIM THE ONLY CHANGE WAS HDG 280 DEGS, AND HE RESUMED HANDLING THE RADIOS. A MIN OR 2 LATER, ZLA DIRECTED US TO TURN L TO 180 DEGS AND ASKED WHAT HDG WE WERE ROLLING THROUGH. THE FO ADVISED '280 DEGS ASSIGNED.' ZLA RESPONDED BY ASKING IF WE RECEIVED A NEW CLRNC AND SAID HIS ORIGINAL CALL WAS TO 'EXPEDITE TO 280' MEANING FL280. WE CLARIFIED THE ALT AND HDG AND CONTINUED THE FLT. CONTRIBUTING FACTORS: SINGLE PLT IN COCKPIT WITH NO XCHK OF RADIO XMISSION AVAILABLE. PREVENTIVE STEPS: ALWAYS USE FULL TITLES OF HDG AND ALT ASSIGNMENTS, IE, FL280 OR HDG 280 DEGS. CONFUSION: EXPEDITE TO 280 VERSUS TURN R TO 280. SUGGESTED PHRASEOLOGY: EXPEDITE THROUGH FL280, MAINTAIN FL240.

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.