Less than standard separation occurred when a pilot took a climb clearance for another aircraft.

Attributes
ACN	153580
Time
Date	199008
Day	Fri
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : apr
State Reference	OH
Altitude	msl bound lower : 13700 msl bound upper : 14000
Environment
Flight Conditions	Marginal
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zlc
Operator	common carrier : air carrier
Make Model Name	Light Transport, Low Wing, 2 Turboprop Eng
Navigation In Use	Other
Flight Phase	climbout : intermediate altitude
Route In Use	enroute airway : zid
Flight Plan	IFR
Aircraft 2
Operator	general aviation : personal
Make Model Name	Small Transport, Low Wing, 2 Turbojet Eng
Flight Phase	climbout : intermediate altitude
Flight Plan	IFR
Person 1
Affiliation	government : faa
Function	controller : radar
Qualification	controller : radar
Experience	controller military : 4 controller non radar : 4 controller radar : 1
ASRS Report	153580
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	conflict : airborne less severe non adherence : required legal separation non adherence : published procedure other anomaly other
Independent Detector	atc equipment other atc equipment : unspecified
Resolutory Action	controller : issued new clearance other
Consequence	faa : investigated
Miss Distance	horizontal : 21606 vertical : 300
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	Operational Error

Narrative:

Light transport Z called on frequency at 14000'. Small transport X called on climbing to 12000'. Small transport Y called on climbing to 12000'. I restated to maintain 12000'. I climbed small transport X to FL190. Small transport Y took the clearance and acknowledged by saying, 'FL190 ty.' I noticed the error when small transport Y was leaving 13200' and advised him to maintain 13000' and issued the light transport Z 14000' traffic. The adep activated and I lost vertical sep before I gained latitude. I was very busy at the time. I had a handoff person to assist me. The frequency was very busy at the time. The fact that small transport Y replied with the #south ty help me to miss the readback. Also, small transport Y was only requesting FL180. If he would have questioned the different I probably would have caught the mistake. When listening to the playback of the error I clearly transmitted small transport X FL190, small transport Y came back weakly on the readback. This also lead to my missing the call sign difference.

Original NASA ASRS Text

Title: LESS THAN STANDARD SEPARATION OCCURRED WHEN A PLT TOOK A CLIMB CLRNC FOR ANOTHER ACFT.

Narrative: LTT Z CALLED ON FREQ AT 14000'. SMT X CALLED ON CLBING TO 12000'. SMT Y CALLED ON CLBING TO 12000'. I RESTATED TO MAINTAIN 12000'. I CLBED SMT X TO FL190. SMT Y TOOK THE CLRNC AND ACKNOWLEDGED BY SAYING, 'FL190 TY.' I NOTICED THE ERROR WHEN SMT Y WAS LEAVING 13200' AND ADVISED HIM TO MAINTAIN 13000' AND ISSUED THE LTT Z 14000' TFC. THE ADEP ACTIVATED AND I LOST VERT SEP BEFORE I GAINED LAT. I WAS VERY BUSY AT THE TIME. I HAD A HDOF PERSON TO ASSIST ME. THE FREQ WAS VERY BUSY AT THE TIME. THE FACT THAT SMT Y REPLIED WITH THE #S TY HELP ME TO MISS THE READBACK. ALSO, SMT Y WAS ONLY REQUESTING FL180. IF HE WOULD HAVE QUESTIONED THE DIFFERENT I PROBABLY WOULD HAVE CAUGHT THE MISTAKE. WHEN LISTENING TO THE PLAYBACK OF THE ERROR I CLEARLY XMITTED SMT X FL190, SMT Y CAME BACK WEAKLY ON THE READBACK. THIS ALSO LEAD TO MY MISSING THE CALL SIGN DIFFERENCE.

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.