Narrative:

Descending for approach at portland, maine, ZBW had cleared us to 11000 ft. During the descent prior to 11000 ft, we were handed off to portland approach (119.75). Approach cleared us to 4000 ft. At 10000 ft we leveled off to slow to 250 KIAS before descending to 4000 ft. Our airspeed prior to level off was 330 KIAS. At this speed it would take us approximately 7-8 mi to slow to 250 KIAS at idle power. While at 10000 ft, approach asked us if we knew that we were cleared to 4000 ft. We acknowledged again our clearance to 4000 ft and told him we were decelerating to 250 KIAS. Again he asked us if we knew we were cleared to 4000 ft. Again I acknowledged and told him as soon as we slowed to 250 KIAS, we would continue the descent. Also, during our descent we were told about traffic at a lower altitude heading in the opposite direction. We did not see the traffic, stated that, and were given a vector to avoid. This had no bearing on our airspeed reduction. It is my understanding that aircraft descending below 10000 ft, are allowed and expected to level off at 10000 ft until 250 KIAS then continue descent. This controller did not appear to know this. It may be possible we were at 10000 ft longer than he was used to seeing. I believe we followed the far's and are not in error.

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Original NASA ASRS Text

Title: FLC OF AN MLG FAILED TO COMPLY WITH ATC CLRNC WHEN THEY LEVELED OFF DURING DSCNT TO SLOW THE ACFT TO THE MAX PERMITTED SPD BELOW 10000 FT.

Narrative: DSNDING FOR APCH AT PORTLAND, MAINE, ZBW HAD CLRED US TO 11000 FT. DURING THE DSCNT PRIOR TO 11000 FT, WE WERE HANDED OFF TO PORTLAND APCH (119.75). APCH CLRED US TO 4000 FT. AT 10000 FT WE LEVELED OFF TO SLOW TO 250 KIAS BEFORE DSNDING TO 4000 FT. OUR AIRSPD PRIOR TO LEVEL OFF WAS 330 KIAS. AT THIS SPD IT WOULD TAKE US APPROX 7-8 MI TO SLOW TO 250 KIAS AT IDLE PWR. WHILE AT 10000 FT, APCH ASKED US IF WE KNEW THAT WE WERE CLRED TO 4000 FT. WE ACKNOWLEDGED AGAIN OUR CLRNC TO 4000 FT AND TOLD HIM WE WERE DECELERATING TO 250 KIAS. AGAIN HE ASKED US IF WE KNEW WE WERE CLRED TO 4000 FT. AGAIN I ACKNOWLEDGED AND TOLD HIM AS SOON AS WE SLOWED TO 250 KIAS, WE WOULD CONTINUE THE DSCNT. ALSO, DURING OUR DSCNT WE WERE TOLD ABOUT TFC AT A LOWER ALT HDG IN THE OPPOSITE DIRECTION. WE DID NOT SEE THE TFC, STATED THAT, AND WERE GIVEN A VECTOR TO AVOID. THIS HAD NO BEARING ON OUR AIRSPD REDUCTION. IT IS MY UNDERSTANDING THAT ACFT DSNDING BELOW 10000 FT, ARE ALLOWED AND EXPECTED TO LEVEL OFF AT 10000 FT UNTIL 250 KIAS THEN CONTINUE DSCNT. THIS CTLR DID NOT APPEAR TO KNOW THIS. IT MAY BE POSSIBLE WE WERE AT 10000 FT LONGER THAN HE WAS USED TO SEEING. I BELIEVE WE FOLLOWED THE FAR'S AND ARE NOT IN ERROR.

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.