Track and heading deviation.

Attributes
ACN	121616
Time
Date	198908
Day	Mon
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : lax
State Reference	CA
Altitude	msl bound lower : 24000 msl bound upper : 24000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zla
Operator	common carrier : air carrier
Make Model Name	Widebody, Low Wing, 2 Turbojet Eng
Navigation In Use	Other Other
Flight Phase	descent other
Route In Use	arrival : profile descent arrival other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time total : 20000 flight time type : 75
ASRS Report	121616
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : instrument pilot : flight engineer pilot : cfi pilot : atp pilot : commercial
Experience	flight time last 90 days : 150 flight time total : 15500 flight time type : 300
ASRS Report	121194
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During civit profile descent to lax air carrier flight, xx received several speed, altitude and heading changes. Flight xx was given a heading change, and descend to 160. I understood the 160 phraseology to be heading 160, ATC questioned our heading, then issued another heading and took us out of the profile. They reinserted us back into the profile. We proceeded to lax and landed as cleared. Supplemental information from acn 121194: reasons: controllers talking too rapidly, plus frequency congestion making clarification impossible. Aircraft design: heading knob and speed knob are identical and are positioned close together. It is not uncommon to turn the wrong knob, particularly in a dark cockpit, and especially if numbers are the same (eg, heading 250, speed 250). Knobs and number drums are physically identical and positioned side by side.

Original NASA ASRS Text

Title: TRACK AND HEADING DEVIATION.

Narrative: DURING CIVIT PROFILE DSCNT TO LAX ACR FLT, XX RECEIVED SEVERAL SPEED, ALT AND HDG CHANGES. FLT XX WAS GIVEN A HDG CHANGE, AND DSND TO 160. I UNDERSTOOD THE 160 PHRASEOLOGY TO BE HDG 160, ATC QUESTIONED OUR HDG, THEN ISSUED ANOTHER HDG AND TOOK US OUT OF THE PROFILE. THEY REINSERTED US BACK INTO THE PROFILE. WE PROCEEDED TO LAX AND LANDED AS CLRED. SUPPLEMENTAL INFORMATION FROM ACN 121194: REASONS: CTLRS TALKING TOO RAPIDLY, PLUS FREQ CONGESTION MAKING CLARIFICATION IMPOSSIBLE. ACFT DESIGN: HDG KNOB AND SPEED KNOB ARE IDENTICAL AND ARE POSITIONED CLOSE TOGETHER. IT IS NOT UNCOMMON TO TURN THE WRONG KNOB, PARTICULARLY IN A DARK COCKPIT, AND ESPECIALLY IF NUMBERS ARE THE SAME (EG, HDG 250, SPEED 250). KNOBS AND NUMBER DRUMS ARE PHYSICALLY IDENTICAL AND POSITIONED SIDE BY SIDE.

Data retrieved from NASA's ASRS site as of August 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.