Descent clearance was missed as a result of frequency congestion.

Attributes
ACN	318020
Time
Date	199510
Day	Tue
Local Time Of Day	0601 To 1200
Place
Locale Reference	atc facility : dxo
State Reference	MI
Altitude	msl bound lower : 18000 msl bound upper : 18000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zob
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent other
Route In Use	arrival other arrival star : star enroute airway : zob
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : flight engineer pilot : atp
Experience	flight time last 90 days : 210 flight time total : 10000 flight time type : 210
ASRS Report	318020
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : flight engineer pilot : cfi pilot : atp
Experience	flight time last 90 days : 90 flight time total : 9500 flight time type : 2000
ASRS Report	318040
Events
Anomaly	other anomaly other
Independent Detector	other flight crewa
Resolutory Action	controller : issued new clearance other
Consequence	Other
Supplementary
Air Traffic Incident	other

Narrative:

Descending into dtw, many aircraft and a lot of frequency congestion, cleared to FL180 and maximum forward speed. At spica intersection, we attempted several times to call ZOB and request lower. We were not answered, and we were stepped on. We finally got through and ZOB stated we were given 12000 ft a couple of times. We never heard that call or acknowledged it. We descended to 12000 ft, no further calls. Flight continued as normal.

Original NASA ASRS Text

Title: DSCNT CLRNC WAS MISSED AS A RESULT OF FREQ CONGESTION.

Narrative: DSNDING INTO DTW, MANY ACFT AND A LOT OF FREQ CONGESTION, CLRED TO FL180 AND MAX FORWARD SPD. AT SPICA INTXN, WE ATTEMPTED SEVERAL TIMES TO CALL ZOB AND REQUEST LOWER. WE WERE NOT ANSWERED, AND WE WERE STEPPED ON. WE FINALLY GOT THROUGH AND ZOB STATED WE WERE GIVEN 12000 FT A COUPLE OF TIMES. WE NEVER HEARD THAT CALL OR ACKNOWLEDGED IT. WE DSNDED TO 12000 FT, NO FURTHER CALLS. FLT CONTINUED AS NORMAL.

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.