Narrative:

I was working the radar when an aircraft called climbing to FL230. The altitudes corresponded to another aircraft I had track control on, and I replied 'air carrier Y ZFW roger, climb and maintain FL290.' the aircraft acknowledged, but the transmission was not very clear. I believed it was air carrier Y. Moments later, an adjoining sector became concerned about an aircraft climbing into their airspace. That aircraft was aircraft X. A moment later, aircraft X called on my frequency (likely as a result of the other sector calling them on 243.), and per their instructions, I assigned aircraft X FL260, and switched aircraft X to the correct frequency. The incident was initially pursued as a pilot deviation, but later, blame was shifted to me and the incident changed to an operational deviation. The quality of the radio xmissions from aircraft X were very poor, making it difficult to understand the entire transmission. This is a standard and common problem amongst military aircraft. The call signs air carrier Y and aircraft X are very dissimilar and pilots should not confuse them. Aircraft X did.

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Original NASA ASRS Text

Title: UNINTENTIONALLY, AN ARTCC CTLR AT ZFW MAY HAVE ALLOWED A MIL ACFT TO ENTER AND CLB IN AN ADJACENT SECTOR WITHOUT A HDOF OR POINTOUT.

Narrative: I WAS WORKING THE RADAR WHEN AN ACFT CALLED CLBING TO FL230. THE ALTS CORRESPONDED TO ANOTHER ACFT I HAD TRACK CTL ON, AND I REPLIED 'ACR Y ZFW ROGER, CLB AND MAINTAIN FL290.' THE ACFT ACKNOWLEDGED, BUT THE XMISSION WAS NOT VERY CLR. I BELIEVED IT WAS ACR Y. MOMENTS LATER, AN ADJOINING SECTOR BECAME CONCERNED ABOUT AN ACFT CLBING INTO THEIR AIRSPACE. THAT ACFT WAS ACFT X. A MOMENT LATER, ACFT X CALLED ON MY FREQ (LIKELY AS A RESULT OF THE OTHER SECTOR CALLING THEM ON 243.), AND PER THEIR INSTRUCTIONS, I ASSIGNED ACFT X FL260, AND SWITCHED ACFT X TO THE CORRECT FREQ. THE INCIDENT WAS INITIALLY PURSUED AS A PLTDEV, BUT LATER, BLAME WAS SHIFTED TO ME AND THE INCIDENT CHANGED TO AN OPDEV. THE QUALITY OF THE RADIO XMISSIONS FROM ACFT X WERE VERY POOR, MAKING IT DIFFICULT TO UNDERSTAND THE ENTIRE XMISSION. THIS IS A STANDARD AND COMMON PROB AMONGST MIL ACFT. THE CALL SIGNS ACR Y AND ACFT X ARE VERY DISSIMILAR AND PLTS SHOULD NOT CONFUSE THEM. ACFT X DID.

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.