Narrative:

ATC cleared us for visual approach approximately 8 mi southwest of the airport. I asked my copilot (PNF) to tune the tower on the alternate tuner for the radio we were using. He tuned the tower on the active tuner, changing from approach to tower without being cleared by ATC. We contacted tower, and they cleared us for an uneventful landing. This was most likely a switchology problem by the copilot (accidental). I have at least 500 hours with this copilot, our cockpit resource management together is excellent and he knows better. All of that said, it was still my responsibility and I should have supervised him more closely.

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Original NASA ASRS Text

Title: APCH CTL CLRED ACFT FOR VISUAL APCH BUT HAD NOT CHANGED THEM OVER TO TWR FREQ. WHEN SETTING TWR FREQ ON ALTERNATE TUNER, FO INADVERTENTLY SET IT ON ACTIVE TUNER AND WAS ON TWR FREQ WITHOUT APCH CTL CLRNC. TWR CLRED THEM TO LAND.

Narrative: ATC CLRED US FOR VISUAL APCH APPROX 8 MI SW OF THE ARPT. I ASKED MY COPLT (PNF) TO TUNE THE TWR ON THE ALTERNATE TUNER FOR THE RADIO WE WERE USING. HE TUNED THE TWR ON THE ACTIVE TUNER, CHANGING FROM APCH TO TWR WITHOUT BEING CLRED BY ATC. WE CONTACTED TWR, AND THEY CLRED US FOR AN UNEVENTFUL LNDG. THIS WAS MOST LIKELY A SWITCHOLOGY PROB BY THE COPLT (ACCIDENTAL). I HAVE AT LEAST 500 HRS WITH THIS COPLT, OUR COCKPIT RESOURCE MGMNT TOGETHER IS EXCELLENT AND HE KNOWS BETTER. ALL OF THAT SAID, IT WAS STILL MY RESPONSIBILITY AND I SHOULD HAVE SUPERVISED HIM MORE CLOSELY.

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.