B757 captain expressed frustration with ZMP controller's approach to airspeed assignments.

Attributes
ACN	614735
Time
Date	200404
Day	Mon
Local Time Of Day	1801 To 2400
Place
Locale Reference	navaid : msp.vortac
State Reference	MN
Altitude	msl single value : 22000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zmp.artcc
Operator	common carrier : air carrier
Make Model Name	B757 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	other
Flight Phase	descent : vacating altitude descent : intermediate altitude
Flight Plan	IFR
Aircraft 2
Controlling Facilities	artcc : zmp.artcc
Make Model Name	Any Unknown or Unlisted Aircraft Manufacturer
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 200 flight time total : 23000 flight time type : 2700
ASRS Report	614735
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
Consequence	faa : reviewed incident with flight crew
Supplementary
Problem Areas	Flight Crew Human Performance ATC Human Performance Aircraft Company
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

About 45 mins out of msp ATC asked us to 'maintain best forward airspeed.' at the time that was about 280 KTS and we agreed to do so. Once we approached the point of the incident, ATC asked what our speed was. The first officer responded '300 KTS.' ATC asked if we could maintain 320 KTS and the first officer said yes without checking with me first. At this point the controller said if we had agreed to do 'best forward' then we should be at 320 KTS not 300 KTS and he chided us for not doing so. As I felt 300 KTS was our best forward speed given the fact there was some light turbulence in the area and the company turbulence speed for their B757 fleet is 290 KTS I told the controller as much. He remained angry with us and told following traffic that we were 'uncooperative.' as the captain of the aircraft I decide what is 'best forward' based upon present conditions. Had we been assigned a 'hard' airspeed I would have notified ATC if we could not maintain it, but that was not the case here. I felt then and I still do that the controller incorrectly admonished us.

Original NASA ASRS Text

Title: B757 CAPT EXPRESSED FRUSTRATION WITH ZMP CTLR'S APCH TO AIRSPD ASSIGNMENTS.

Narrative: ABOUT 45 MINS OUT OF MSP ATC ASKED US TO 'MAINTAIN BEST FORWARD AIRSPD.' AT THE TIME THAT WAS ABOUT 280 KTS AND WE AGREED TO DO SO. ONCE WE APCHED THE POINT OF THE INCIDENT, ATC ASKED WHAT OUR SPD WAS. THE FO RESPONDED '300 KTS.' ATC ASKED IF WE COULD MAINTAIN 320 KTS AND THE FO SAID YES WITHOUT CHKING WITH ME FIRST. AT THIS POINT THE CTLR SAID IF WE HAD AGREED TO DO 'BEST FORWARD' THEN WE SHOULD BE AT 320 KTS NOT 300 KTS AND HE CHIDED US FOR NOT DOING SO. AS I FELT 300 KTS WAS OUR BEST FORWARD SPD GIVEN THE FACT THERE WAS SOME LIGHT TURB IN THE AREA AND THE COMPANY TURB SPD FOR THEIR B757 FLEET IS 290 KTS I TOLD THE CTLR AS MUCH. HE REMAINED ANGRY WITH US AND TOLD FOLLOWING TFC THAT WE WERE 'UNCOOPERATIVE.' AS THE CAPT OF THE ACFT I DECIDE WHAT IS 'BEST FORWARD' BASED UPON PRESENT CONDITIONS. HAD WE BEEN ASSIGNED A 'HARD' AIRSPD I WOULD HAVE NOTIFIED ATC IF WE COULD NOT MAINTAIN IT, BUT THAT WAS NOT THE CASE HERE. I FELT THEN AND I STILL DO THAT THE CTLR INCORRECTLY ADMONISHED US.

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.