B737 flight crew landing ord expressed frustration regarding ATC assigned speed of 160 KTS.

Attributes
ACN	597389
Time
Date	200310
Day	Sat
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : c90.tracon
State Reference	IL
Altitude	msl single value : 8000
Environment
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : c90.tracon
Operator	common carrier : air carrier
Make Model Name	B737-500
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Route In Use	arrival : on vectors
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
ASRS Report	597389
Person 2
Affiliation	company : air carrier
Function	flight crew : first officer
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted
Supplementary
Problem Areas	ATC Human Performance Aircraft Flight Crew Human Performance
Primary Problem	Ambiguous

Narrative:

Just after switching over to approach control, heard controller giving speeds of 160 KTS to all the aircraft. In fact, we also got an assigned speed of 160 KTS while still around 4000 ft. Not really a complaint as such, but could someone remind the controllers that when speeds of less than 170 KTS are assigned to the B737's, we must lower the gear in order to select the proper flap setting. The occasional assignment of speeds of less than 170 KTS is ok, but it really adds to our fuel burn when it happens repeatedly. It appeared that today, the controller was using 160 KTS for all approachs, which leads me to believe the spacing could have been different to begin with. I would not be surprised if the controller was not aware of the speed restrs we have on our guppies. (We can go as slow as 170 KTS using flaps 10 degrees. Any slower requires flaps 15+ degrees. Whenever we use flaps 15+ degrees, we have to lower the gear in order to get rid of the flap warning horn.)

Original NASA ASRS Text

Title: B737 FLT CREW LNDG ORD EXPRESSED FRUSTRATION REGARDING ATC ASSIGNED SPD OF 160 KTS.

Narrative: JUST AFTER SWITCHING OVER TO APCH CTL, HEARD CTLR GIVING SPDS OF 160 KTS TO ALL THE ACFT. IN FACT, WE ALSO GOT AN ASSIGNED SPD OF 160 KTS WHILE STILL AROUND 4000 FT. NOT REALLY A COMPLAINT AS SUCH, BUT COULD SOMEONE REMIND THE CTLRS THAT WHEN SPDS OF LESS THAN 170 KTS ARE ASSIGNED TO THE B737'S, WE MUST LOWER THE GEAR IN ORDER TO SELECT THE PROPER FLAP SETTING. THE OCCASIONAL ASSIGNMENT OF SPDS OF LESS THAN 170 KTS IS OK, BUT IT REALLY ADDS TO OUR FUEL BURN WHEN IT HAPPENS REPEATEDLY. IT APPEARED THAT TODAY, THE CTLR WAS USING 160 KTS FOR ALL APCHS, WHICH LEADS ME TO BELIEVE THE SPACING COULD HAVE BEEN DIFFERENT TO BEGIN WITH. I WOULD NOT BE SURPRISED IF THE CTLR WAS NOT AWARE OF THE SPD RESTRS WE HAVE ON OUR GUPPIES. (WE CAN GO AS SLOW AS 170 KTS USING FLAPS 10 DEGS. ANY SLOWER REQUIRES FLAPS 15+ DEGS. WHENEVER WE USE FLAPS 15+ DEGS, WE HAVE TO LOWER THE GEAR IN ORDER TO GET RID OF THE FLAP WARNING HORN.)

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.