Narrative:

Aircraft speed. New first officer was flying this leg. We had, by previous controller, been assigned FL300. I was completing checklists when approach asked us our speed. I realized that the first officer had slowed to 250 KTS after he had leveled from the previous descent. Chicago reminded us that we had been given 300 KTS. We were then told, since we had slowed, to now descend to 7000 ft. No further reference was made by the controller. I told the first officer how important, especially in chicago's airspace, it is not to slow without their blessing. I take responsibility for not having caught it immediately.

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Original NASA ASRS Text

Title: MD80 CREW HAD SPD DEV.

Narrative: ACFT SPD. NEW FO WAS FLYING THIS LEG. WE HAD, BY PREVIOUS CTLR, BEEN ASSIGNED FL300. I WAS COMPLETING CHKLISTS WHEN APCH ASKED US OUR SPD. I REALIZED THAT THE FO HAD SLOWED TO 250 KTS AFTER HE HAD LEVELED FROM THE PREVIOUS DSCNT. CHICAGO REMINDED US THAT WE HAD BEEN GIVEN 300 KTS. WE WERE THEN TOLD, SINCE WE HAD SLOWED, TO NOW DSND TO 7000 FT. NO FURTHER REF WAS MADE BY THE CTLR. I TOLD THE FO HOW IMPORTANT, ESPECIALLY IN CHICAGO'S AIRSPACE, IT IS NOT TO SLOW WITHOUT THEIR BLESSING. I TAKE RESPONSIBILITY FOR NOT HAVING CAUGHT IT IMMEDIATELY.

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.