Narrative:

Captain was off frequency checking in with company. First officer was PF, received descent clearance out of 10000 ft MSL. Due to momentary loss of altitude situational awareness failed to slow aircraft to 250 KIAS or less prior to initiating descent. Captain came back on frequency and called speed excursion out to first officer who initiated immediate speed reduction. First officer stated ATC queried his speed and he acknowledged greater than 250 KIAS below 10000 ft. Total time of speed excursion less than 2 mins and within 2000 ft of descent from 10000 ft MSL. First officer indicated onset of seasonal flu created distraction and subsequently went home ill prior to end of 3 day assignment. I believe crew coordination allowed us to catch this deviation in a timely fashion and correction was made immediately, although I regret not seeing it immediately due to preoccupation with other cockpit task. First officer said he relearned the effects illness can have on his performance and will be more wary in future. Crew conducted postflt CRM debrief to examine clearance. Supplemental information from acn 598639: it was a complete oversight and was not intentional to fly over 250 KTS. Cvg acknowledged the transmission and did not ask us to slow, nor did they ask why we were cruising at 300 KTS. I believe that the short flight, combined with 1 pilot off frequency, and flying at an unusually low cruise altitude (10000 ft planned cruise altitude) were some contributing factors/considerations that led to this event.

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Original NASA ASRS Text

Title: A CL65 FLT CREW INADVERTENTLY ARE AT 300 KTS BELOW 10000 FT.

Narrative: CAPT WAS OFF FREQ CHKING IN WITH COMPANY. FO WAS PF, RECEIVED DSCNT CLRNC OUT OF 10000 FT MSL. DUE TO MOMENTARY LOSS OF ALT SITUATIONAL AWARENESS FAILED TO SLOW ACFT TO 250 KIAS OR LESS PRIOR TO INITIATING DSCNT. CAPT CAME BACK ON FREQ AND CALLED SPD EXCURSION OUT TO FO WHO INITIATED IMMEDIATE SPD REDUCTION. FO STATED ATC QUERIED HIS SPD AND HE ACKNOWLEDGED GREATER THAN 250 KIAS BELOW 10000 FT. TOTAL TIME OF SPD EXCURSION LESS THAN 2 MINS AND WITHIN 2000 FT OF DSCNT FROM 10000 FT MSL. FO INDICATED ONSET OF SEASONAL FLU CREATED DISTR AND SUBSEQUENTLY WENT HOME ILL PRIOR TO END OF 3 DAY ASSIGNMENT. I BELIEVE CREW COORD ALLOWED US TO CATCH THIS DEV IN A TIMELY FASHION AND CORRECTION WAS MADE IMMEDIATELY, ALTHOUGH I REGRET NOT SEEING IT IMMEDIATELY DUE TO PREOCCUPATION WITH OTHER COCKPIT TASK. FO SAID HE RELEARNED THE EFFECTS ILLNESS CAN HAVE ON HIS PERFORMANCE AND WILL BE MORE WARY IN FUTURE. CREW CONDUCTED POSTFLT CRM DEBRIEF TO EXAMINE CLRNC. SUPPLEMENTAL INFO FROM ACN 598639: IT WAS A COMPLETE OVERSIGHT AND WAS NOT INTENTIONAL TO FLY OVER 250 KTS. CVG ACKNOWLEDGED THE XMISSION AND DID NOT ASK US TO SLOW, NOR DID THEY ASK WHY WE WERE CRUISING AT 300 KTS. I BELIEVE THAT THE SHORT FLT, COMBINED WITH 1 PLT OFF FREQ, AND FLYING AT AN UNUSUALLY LOW CRUISE ALT (10000 FT PLANNED CRUISE ALT) WERE SOME CONTRIBUTING FACTORS/CONSIDERATIONS THAT LED TO THIS EVENT.

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.