Narrative:

We taxied out for takeoff at lax using the #1 radio. It worked fine for ground control. We switched to tower frequency to cross runways 25L and runway 25R again on the #1 radio. All communications were normal. We were cleared into position and hold on runway 25R. While in position, no other communications were heard for about 2 mins. We then heard the tower calling us on 121.5 which was set on the #2 radio. At that time we were cleared for takeoff. The #1 radio appeared to be working again, but later failed intermittently. This was a very unusual problem and monitoring 121.5 on the #2 radio helped the situation.

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Original NASA ASRS Text

Title: A DC-10 FLT CREW HAS AN INTERMITTENT RADIO PROB.

Narrative: WE TAXIED OUT FOR TKOF AT LAX USING THE #1 RADIO. IT WORKED FINE FOR GND CTL. WE SWITCHED TO TWR FREQ TO CROSS RWYS 25L AND RWY 25R AGAIN ON THE #1 RADIO. ALL COMS WERE NORMAL. WE WERE CLRED INTO POS AND HOLD ON RWY 25R. WHILE IN POSITION, NO OTHER COMS WERE HEARD FOR ABOUT 2 MINS. WE THEN HEARD THE TWR CALLING US ON 121.5 WHICH WAS SET ON THE #2 RADIO. AT THAT TIME WE WERE CLRED FOR TKOF. THE #1 RADIO APPEARED TO BE WORKING AGAIN, BUT LATER FAILED INTERMITTENTLY. THIS WAS A VERY UNUSUAL PROB AND MONITORING 121.5 ON THE #2 RADIO HELPED THE SIT.

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.