Crew was issued go around vectors for spacing at sea.

Attributes
ACN	453298
Time
Date	199910
Day	Fri
Local Time Of Day	0601 To 1200
Place
State Reference	WA
Altitude	msl single value : 3500
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : s46.tracon
Operator	common carrier : air carrier
Make Model Name	Medium Large Transport, Low Wing, 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Plan	IFR
Aircraft 2
Navigation In Use	ils localizer only : 16r
Flight Phase	descent : approach descent : intermediate altitude
Route In Use	arrival : on vectors
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 240 flight time total : 11500 flight time type : 7500
ASRS Report	453298
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp
Experience	flight time last 90 days : 270 flight time total : 4300 flight time type : 850
ASRS Report	453212
Events
Anomaly	non adherence : far non adherence : published procedure other anomaly
Independent Detector	other controllera
Resolutory Action	controller : issued new clearance
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	FAA ATC Human Performance Flight Crew Human Performance ATC Facility
Primary Problem	ATC Human Performance
Situations
ATC Facility	procedure or policy : s46.tracon

Narrative:

Assigned 170 KIAS on base/dogleg. Turned final and cleared for ILS approach to runway 16R at 17 DME. I was told to maintain 170 KIAS until the marker (parkk 5.8 DME). At 11 DME, due to TCASII traffic at 3 mi and closing, I slowed to 160 KIAS. At approximately 10 DME sea approach broke us out of traffic (heading 090 degrees and 3000 ft). Problem occurred because I failed to inform sea approach that I was slowing my aircraft to maintain separation on the aircraft ahead. I called sea approach when I got on the ground to discuss the situation. The watch supervisor explained the breakout was necessary because of traffic following closely behind me. Lesson learned: if the pilot needs to take steps to keep his flight safe, tell ATC. Even if you think it is only a small change (and no one will notice), tell ATC -- they will revise the game plan.

Original NASA ASRS Text

Title: CREW WAS ISSUED GAR VECTORS FOR SPACING AT SEA.

Narrative: ASSIGNED 170 KIAS ON BASE/DOGLEG. TURNED FINAL AND CLRED FOR ILS APCH TO RWY 16R AT 17 DME. I WAS TOLD TO MAINTAIN 170 KIAS UNTIL THE MARKER (PARKK 5.8 DME). AT 11 DME, DUE TO TCASII TFC AT 3 MI AND CLOSING, I SLOWED TO 160 KIAS. AT APPROX 10 DME SEA APCH BROKE US OUT OF TFC (HDG 090 DEGS AND 3000 FT). PROB OCCURRED BECAUSE I FAILED TO INFORM SEA APCH THAT I WAS SLOWING MY ACFT TO MAINTAIN SEPARATION ON THE ACFT AHEAD. I CALLED SEA APCH WHEN I GOT ON THE GND TO DISCUSS THE SIT. THE WATCH SUPVR EXPLAINED THE BREAKOUT WAS NECESSARY BECAUSE OF TFC FOLLOWING CLOSELY BEHIND ME. LESSON LEARNED: IF THE PLT NEEDS TO TAKE STEPS TO KEEP HIS FLT SAFE, TELL ATC. EVEN IF YOU THINK IT IS ONLY A SMALL CHANGE (AND NO ONE WILL NOTICE), TELL ATC -- THEY WILL REVISE THE GAME PLAN.

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.