Narrative:

Shortly after leveloff at cruise, first officer heard an mlt callup and recognized the call sign as one from his 'old unit' and he said he wondered if 'so-and-so' was still there, followed immediately by him asking the mlt to come up 123.45. I had a somewhat vague feeling that frequency was restr and said so. He assured me that he had used it a lot in military air command, no questions asked. I should have told him not to do it just on grounds of not being very professional, but let him go ahead, and he was on it (123.45) about a minute. Found out later, checking with 'the guy in the office', that my vague feeling was caused by an operations bulletin about 7 months ago, stating that frequency is illegal for air-to-air. Have since spoken to first officer and myself about never doing that again.

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Original NASA ASRS Text

Title: FLT CREW MEMBER USED RESTRICTED FREQ TO COMMUNICATE WITH 'OLD UNIT' WHEN HEARD CALL TO CENTER.

Narrative: SHORTLY AFTER LEVELOFF AT CRUISE, F/O HEARD AN MLT CALLUP AND RECOGNIZED THE CALL SIGN AS ONE FROM HIS 'OLD UNIT' AND HE SAID HE WONDERED IF 'SO-AND-SO' WAS STILL THERE, FOLLOWED IMMEDIATELY BY HIM ASKING THE MLT TO COME UP 123.45. I HAD A SOMEWHAT VAGUE FEELING THAT FREQ WAS RESTR AND SAID SO. HE ASSURED ME THAT HE HAD USED IT A LOT IN MIL AIR COMMAND, NO QUESTIONS ASKED. I SHOULD HAVE TOLD HIM NOT TO DO IT JUST ON GROUNDS OF NOT BEING VERY PROFESSIONAL, BUT LET HIM GO AHEAD, AND HE WAS ON IT (123.45) ABOUT A MINUTE. FOUND OUT LATER, CHECKING WITH 'THE GUY IN THE OFFICE', THAT MY VAGUE FEELING WAS CAUSED BY AN OPERATIONS BULLETIN ABOUT 7 MONTHS AGO, STATING THAT FREQ IS ILLEGAL FOR AIR-TO-AIR. HAVE SINCE SPOKEN TO F/O AND MYSELF ABOUT NEVER DOING THAT AGAIN.

Data retrieved from NASA's ASRS site as of August 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.