Narrative:

While we were descending from 7000 ft to 5000 ft MSL, ATC asked what our speed was. The first officer replied that we were slowing through 250 KTS to our assigned 170 KTS. I was flying and had been looking outside for traffic. When I heard the reply, I looked at the airspeed, which was 255 KTS. I attribute my lack of situational awareness to 2 nights of very little sleep. The first night was a reduced rest of 8 hours because we had to wait for a connecting flight attendant. In addition to a late departure, when we arrived at our destination, we were sent to the wrong hotel. This was the first overnight at a new station for our company. We may have gotten about 4 hours sleep. The second night, we were at a hotel with noisy adults and children running up and down the hallway until about midnight. We might have received 4 hours sleep that night. I couldn't recall if we had been given any speed restr prior to the 170 KT assignment. After landing, I removed myself from the trip. I figured that if I was fatigued enough to miss something as basic as airspeed control, I did not belong on the flight deck.

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Original NASA ASRS Text

Title: AIRSPD DEV FROM ASSIGNED AIRSPD RPTED AS OVER 250 KTS BELOW 10000 FT BY A PIC OF A CRJ INTO ORD, IL.

Narrative: WHILE WE WERE DSNDING FROM 7000 FT TO 5000 FT MSL, ATC ASKED WHAT OUR SPD WAS. THE FO REPLIED THAT WE WERE SLOWING THROUGH 250 KTS TO OUR ASSIGNED 170 KTS. I WAS FLYING AND HAD BEEN LOOKING OUTSIDE FOR TFC. WHEN I HEARD THE REPLY, I LOOKED AT THE AIRSPD, WHICH WAS 255 KTS. I ATTRIBUTE MY LACK OF SITUATIONAL AWARENESS TO 2 NIGHTS OF VERY LITTLE SLEEP. THE FIRST NIGHT WAS A REDUCED REST OF 8 HRS BECAUSE WE HAD TO WAIT FOR A CONNECTING FLT ATTENDANT. IN ADDITION TO A LATE DEP, WHEN WE ARRIVED AT OUR DEST, WE WERE SENT TO THE WRONG HOTEL. THIS WAS THE FIRST OVERNIGHT AT A NEW STATION FOR OUR COMPANY. WE MAY HAVE GOTTEN ABOUT 4 HRS SLEEP. THE SECOND NIGHT, WE WERE AT A HOTEL WITH NOISY ADULTS AND CHILDREN RUNNING UP AND DOWN THE HALLWAY UNTIL ABOUT MIDNIGHT. WE MIGHT HAVE RECEIVED 4 HRS SLEEP THAT NIGHT. I COULDN'T RECALL IF WE HAD BEEN GIVEN ANY SPD RESTR PRIOR TO THE 170 KT ASSIGNMENT. AFTER LNDG, I REMOVED MYSELF FROM THE TRIP. I FIGURED THAT IF I WAS FATIGUED ENOUGH TO MISS SOMETHING AS BASIC AS AIRSPD CTL, I DID NOT BELONG ON THE FLT DECK.

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.