Air carrier large transport deviated from clearance route.

Attributes
ACN	96718
Time
Date	198810
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : buj airport : dfw
State Reference	TX
Altitude	msl bound lower : 24000 msl bound upper : 24000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zfw tower : lax
Operator	common carrier : air carrier
Make Model Name	Large Transport, Low Wing, 3 Turbojet Eng
Flight Phase	cruise other
Route In Use	enroute : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : instrument pilot : atp
Experience	flight time last 90 days : 200 flight time total : 5800 flight time type : 2800
ASRS Report	96718
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp pilot : flight engineer pilot : cfi
Experience	flight time last 90 days : 200 flight time total : 10000 flight time type : 7000
ASRS Report	96734
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
Situations
ATC Facility	procedure or policy : unspecified

Narrative:

Controller was busy giving headings and speed restrictions for spacing. Gave us a heading. There was confusion amongst the crew whether the assigned heading was 170 degree or 270 degree. (Several other aircraft on the arrival were being given 270 degree). Captain attempted several times to verify heading with controller but was blocked and/or unable because of frequency congestion. First officer began turn to 270 degree. Finally controller verified the assigned heading was 170 degree. First officer changed direction of turn. No resulting conflicts are known. Classic example of a controller being overloaded causing a breakdown in communications. Supplemental information from acn 96734. Controller gave a vector of L-170, read back by the captain. First officer understood R-270 and started a right turn to 270. When finally acknowledging our calls, the controller gave us direct buj.

Original NASA ASRS Text

Title: ACR LGT DEVIATED FROM CLRNC ROUTE.

Narrative: CTLR WAS BUSY GIVING HDGS AND SPD RESTRICTIONS FOR SPACING. GAVE US A HDG. THERE WAS CONFUSION AMONGST THE CREW WHETHER THE ASSIGNED HDG WAS 170 DEG OR 270 DEG. (SEVERAL OTHER ACFT ON THE ARR WERE BEING GIVEN 270 DEG). CAPT ATTEMPTED SEVERAL TIMES TO VERIFY HDG WITH CTLR BUT WAS BLOCKED AND/OR UNABLE BECAUSE OF FREQ CONGESTION. F/O BEGAN TURN TO 270 DEG. FINALLY CTLR VERIFIED THE ASSIGNED HDG WAS 170 DEG. F/O CHANGED DIRECTION OF TURN. NO RESULTING CONFLICTS ARE KNOWN. CLASSIC EXAMPLE OF A CTLR BEING OVERLOADED CAUSING A BREAKDOWN IN COMS. SUPPLEMENTAL INFO FROM ACN 96734. CTLR GAVE A VECTOR OF L-170, READ BACK BY THE CAPT. F/O UNDERSTOOD R-270 AND STARTED A R TURN TO 270. WHEN FINALLY ACKNOWLEDGING OUR CALLS, THE CTLR GAVE US DIRECT BUJ.

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.