Flight crew failed to comply with ATC clearance. Pilot deviation.

Attributes
ACN	127368
Time
Date	198910
Day	Tue
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : sea
State Reference	WA
Altitude	msl bound lower : 6000 msl bound upper : 6000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : sea
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Route In Use	departure other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 145 flight time total : 9505
ASRS Report	127368
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 320 flight time total : 17000
ASRS Report	126727
Events
Anomaly	non adherence : clearance other spatial deviation
Independent Detector	other controllera
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Taking off north on the summa two departure at the seatac airport, we failed to make the turn at the 8 DME fix to a 070 heading. After takeoff tower instructed us to track the 338 radial and contact departure. Departure called out conflicting traffic. I thought he wanted us to maintain the last heading because of traffic. Departure then told us we were clear of traffic then informed us we were late on our turn. We initiated the turn at that time (approximately 6000') and continued on the summa two departure without incident.

Original NASA ASRS Text

Title: FLT CREW FAILED TO COMPLY WITH ATC CLRNC. PLT DEVIATION.

Narrative: TAKING OFF NORTH ON THE SUMMA TWO DEP AT THE SEATAC ARPT, WE FAILED TO MAKE THE TURN AT THE 8 DME FIX TO A 070 HDG. AFTER TKOF TWR INSTRUCTED US TO TRACK THE 338 RADIAL AND CONTACT DEP. DEP CALLED OUT CONFLICTING TFC. I THOUGHT HE WANTED US TO MAINTAIN THE LAST HDG BECAUSE OF TFC. DEP THEN TOLD US WE WERE CLEAR OF TFC THEN INFORMED US WE WERE LATE ON OUR TURN. WE INITIATED THE TURN AT THAT TIME (APPROX 6000') AND CONTINUED ON THE SUMMA TWO DEP WITHOUT INCIDENT.

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.