Narrative:

On apr/wed/02, I was the PIC for the flight operated by air carrier X from mht to iad. About 20 mi south of the bwz VOR, I (PNF) switched off the main frequency to make a passenger announcement (required by our flight operations manual). During the time I was off, my first officer was given a clearance to descend to FL200. He acknowledge the controller and programmed the autoplt to FL200. Shortly after (according to him) he thought he understood a clearance to FL190. He set the autoplt accordingly. When I came back on frequency, he briefed me that a descent to FL190 (which we wre near leveling) was issued. A little bit of time later, I noticed an aircraft approaching from the east. I queried ATC and I was asked my altitude I advised ATC that we were leveling at FL190 and that I had noted some traffic. There were no TA/RA advisories and no action taken by either aircraft. After the aircraft passed, the controller advised me that we were only cleared to FL200. I had a discussion with the first officer who stated that he understood the clearance to be FL190. No further action was taken and shortly we were handed off to another controller. The flight continued to the destination without further incident. On the ground, I made notification to our ATC manager, chief pilot and the ATC supervisor for ZNY. I advised them of the incident and also advised them that we were able to maintain visual contact at all times with the aircraft. I filed the required paperwork.

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Original NASA ASRS Text

Title: A CARJ CREW RESPONDED TO WHAT THEY THOUGHT WAS A CLRNC TO DSND FROM FL200 TO FL190. THE CREW'S QUERY OF ATC ABOUT SIGHTED TFC, REVEALED THEIR DSCNT TO FL190 WAS IN ERROR.

Narrative: ON APR/WED/02, I WAS THE PIC FOR THE FLT OPERATED BY ACR X FROM MHT TO IAD. ABOUT 20 MI S OF THE BWZ VOR, I (PNF) SWITCHED OFF THE MAIN FREQ TO MAKE A PAX ANNOUNCEMENT (REQUIRED BY OUR FLT OPS MANUAL). DURING THE TIME I WAS OFF, MY FO WAS GIVEN A CLRNC TO DSND TO FL200. HE ACKNOWLEDGE THE CTLR AND PROGRAMMED THE AUTOPLT TO FL200. SHORTLY AFTER (ACCORDING TO HIM) HE THOUGHT HE UNDERSTOOD A CLRNC TO FL190. HE SET THE AUTOPLT ACCORDINGLY. WHEN I CAME BACK ON FREQ, HE BRIEFED ME THAT A DSCNT TO FL190 (WHICH WE WRE NEAR LEVELING) WAS ISSUED. A LITTLE BIT OF TIME LATER, I NOTICED AN ACFT APCHING FROM THE E. I QUERIED ATC AND I WAS ASKED MY ALT I ADVISED ATC THAT WE WERE LEVELING AT FL190 AND THAT I HAD NOTED SOME TFC. THERE WERE NO TA/RA ADVISORIES AND NO ACTION TAKEN BY EITHER ACFT. AFTER THE ACFT PASSED, THE CTLR ADVISED ME THAT WE WERE ONLY CLRED TO FL200. I HAD A DISCUSSION WITH THE FO WHO STATED THAT HE UNDERSTOOD THE CLRNC TO BE FL190. NO FURTHER ACTION WAS TAKEN AND SHORTLY WE WERE HANDED OFF TO ANOTHER CTLR. THE FLT CONTINUED TO THE DEST WITHOUT FURTHER INCIDENT. ON THE GND, I MADE NOTIFICATION TO OUR ATC MGR, CHIEF PLT AND THE ATC SUPVR FOR ZNY. I ADVISED THEM OF THE INCIDENT AND ALSO ADVISED THEM THAT WE WERE ABLE TO MAINTAIN VISUAL CONTACT AT ALL TIMES WITH THE ACFT. I FILED THE REQUIRED PAPERWORK.

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.