B777 pilot slows below ATC assigned speed causing go around at ord.

Attributes
ACN	606548
Time
Date	200401
Day	Wed
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : c90.tracon
State Reference	FL
Altitude	msl single value : 4000
Environment
Flight Conditions	IMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : c90.tracon
Operator	common carrier : air carrier
Make Model Name	B777-200
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 60 flight time total : 15000 flight time type : 500
ASRS Report	606548
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	non adherence : clearance other anomaly
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance flight crew : executed go around
Supplementary
Problem Areas	Flight Crew Human Performance Airport Weather
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

Held at teddy intersection for approximately 20 mins, then vectored for runway 22R ILS in IFR conditions. During vectors, approach control sequenced us pretty tight to the aircraft in front of us and told us to maintain 170 KTS to the marker. I started to slow to approach speed about 1 NM prior to the marker and ATC took deference to that. I was on an IFR approach to a patchy snow covered runway and didn't want to have to go around due to another aircraft still on the runway is why I elected to start the slowdown 1 mi early. ATC had to break out a flight who was behind us and send him over to runway 27. I don't know how close ATC vectored that other aircraft behind us, but approach was trying hard to get everyone sequenced for arrs to the 2 runways in use.

Original NASA ASRS Text

Title: B777 PLT SLOWS BELOW ATC ASSIGNED SPD CAUSING GAR AT ORD.

Narrative: HELD AT TEDDY INTXN FOR APPROX 20 MINS, THEN VECTORED FOR RWY 22R ILS IN IFR CONDITIONS. DURING VECTORS, APCH CTL SEQUENCED US PRETTY TIGHT TO THE ACFT IN FRONT OF US AND TOLD US TO MAINTAIN 170 KTS TO THE MARKER. I STARTED TO SLOW TO APCH SPD ABOUT 1 NM PRIOR TO THE MARKER AND ATC TOOK DEFERENCE TO THAT. I WAS ON AN IFR APCH TO A PATCHY SNOW COVERED RWY AND DIDN'T WANT TO HAVE TO GO AROUND DUE TO ANOTHER ACFT STILL ON THE RWY IS WHY I ELECTED TO START THE SLOWDOWN 1 MI EARLY. ATC HAD TO BREAK OUT A FLT WHO WAS BEHIND US AND SEND HIM OVER TO RWY 27. I DON'T KNOW HOW CLOSE ATC VECTORED THAT OTHER ACFT BEHIND US, BUT APCH WAS TRYING HARD TO GET EVERYONE SEQUENCED FOR ARRS TO THE 2 RWYS IN USE.

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.