Narrative:

Atx X departed detroit city airport, climbing sbound to FL130, requesting FL160. Air carrier Y, overflt nwbound at FL160. Upon entering my airspace, I climbed X to FL160. Went and did a couple other controller actions. I realized my mistake. I tried to stop atx X at FL150. Pilot read back that he was descending back down to FL150. Had X get Y in sight and maintain visual separation. Supplemental information from acn 303338: on a flight from detroit city airport to mansfield ohio, the following occurred. We were flying a learjet on vectors maintaining a heading of 210 degrees south of detroit. We were climbing on a clearance to 16000 ft. Climbing through 15500 ft, the controller asked us to descend to 15000 ft adding there was traffic at 1 O'clock and 1 mi at 16000 ft on a perpendicular heading. We idented the traffic visually. I immediately initiated a descent stopping the climb at 15600 ft. The traffic passed overhead as we were descending through 15500 ft, therefore passing 500 ft above us. The rest of the flight continued without incident. Supplemental information from acn 302350: ATC then called 'traffic 8-9 O'clock level 16000 ft,' we both looked. I could not see the traffic because of its relative position, above and directly off the left wing. The captain could see it and advised ATC 'traffic in sight.' we were told to maintain visual separation with the traffic, which the PF did. Descending back through 15700 ft a beech 1900 passed directly overhead, which was the first I had seen the traffic.

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Original NASA ASRS Text

Title: ATX X CLB TO OCCUPIED ALT HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: ATX X DEPARTED DETROIT CITY ARPT, CLBING SBOUND TO FL130, REQUESTING FL160. ACR Y, OVERFLT NWBOUND AT FL160. UPON ENTERING MY AIRSPACE, I CLBED X TO FL160. WENT AND DID A COUPLE OTHER CTLR ACTIONS. I REALIZED MY MISTAKE. I TRIED TO STOP ATX X AT FL150. PLT READ BACK THAT HE WAS DSNDING BACK DOWN TO FL150. HAD X GET Y IN SIGHT AND MAINTAIN VISUAL SEPARATION. SUPPLEMENTAL INFO FROM ACN 303338: ON A FLT FROM DETROIT CITY ARPT TO MANSFIELD OHIO, THE FOLLOWING OCCURRED. WE WERE FLYING A LEARJET ON VECTORS MAINTAINING A HDG OF 210 DEGS S OF DETROIT. WE WERE CLBING ON A CLRNC TO 16000 FT. CLBING THROUGH 15500 FT, THE CTLR ASKED US TO DSND TO 15000 FT ADDING THERE WAS TFC AT 1 O'CLOCK AND 1 MI AT 16000 FT ON A PERPENDICULAR HDG. WE IDENTED THE TFC VISUALLY. I IMMEDIATELY INITIATED A DSCNT STOPPING THE CLB AT 15600 FT. THE TFC PASSED OVERHEAD AS WE WERE DSNDING THROUGH 15500 FT, THEREFORE PASSING 500 FT ABOVE US. THE REST OF THE FLT CONTINUED WITHOUT INCIDENT. SUPPLEMENTAL INFO FROM ACN 302350: ATC THEN CALLED 'TFC 8-9 O'CLOCK LEVEL 16000 FT,' WE BOTH LOOKED. I COULD NOT SEE THE TFC BECAUSE OF ITS RELATIVE POS, ABOVE AND DIRECTLY OFF THE L WING. THE CAPT COULD SEE IT AND ADVISED ATC 'TFC IN SIGHT.' WE WERE TOLD TO MAINTAIN VISUAL SEPARATION WITH THE TFC, WHICH THE PF DID. DSNDING BACK THROUGH 15700 FT A BEECH 1900 PASSED DIRECTLY OVERHEAD, WHICH WAS THE FIRST I HAD SEEN THE TFC.

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.