Narrative:

Dec/xa/00 I was making a local flight with departure from montgomery airport, san diego, ca, about XA09. I have a new portable intercom in my C175 and it was ingesting noise into the radio system so that I was having difficulty communicating with the tower. I should have returned to base. But, instead, I thought I had clearance for takeoff when, in fact, I did not. As a result, I caused the tower to order a go around for another aircraft.

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Original NASA ASRS Text

Title: A C175 PLT THOUGHT HE HAD CLRNC FOR TKOF WHEN, IN FACT, HE DID NOT AT MYF.

Narrative: DEC/XA/00 I WAS MAKING A LCL FLT WITH DEP FROM MONTGOMERY ARPT, SAN DIEGO, CA, ABOUT XA09. I HAVE A NEW PORTABLE INTERCOM IN MY C175 AND IT WAS INGESTING NOISE INTO THE RADIO SYS SO THAT I WAS HAVING DIFFICULTY COMMUNICATING WITH THE TWR. I SHOULD HAVE RETURNED TO BASE. BUT, INSTEAD, I THOUGHT I HAD CLRNC FOR TKOF WHEN, IN FACT, I DID NOT. AS A RESULT, I CAUSED THE TWR TO ORDER A GAR FOR ANOTHER ACFT.

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.