Narrative:

At takeoff from pain field as a flight of 2, the other pilot misinterpreted my hand signal as a clearance to takeoff, making an unauthorized takeoff. We had been waiting to takeoff from runway 29 for about 3 mins, on the runway in a hold position. The tower approved takeoff approximately 10-15 seconds after the other aircraft lifted off the runway. Other aircraft's radio was intermittent. I was doing the radio communications for both aircraft. I was advised to phone the tower as soon as possible. The problem was enhanced by the other pilot's radio. This radio became intermittent as we were preparing for takeoff. We had agreed that I would do the radio communications with the tower as a flight of 2. I had not advised the tower of the radio problem. I believe that I should have advised the tower of the radio problem and ask for a light signal for takeoff clearance.

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Original NASA ASRS Text

Title: GA SMA UNAUTH TKOF FROM PAE.

Narrative: AT TKOF FROM PAIN FIELD AS A FLT OF 2, THE OTHER PLT MISINTERPRETED MY HAND SIGNAL AS A CLRNC TO TKOF, MAKING AN UNAUTH TKOF. WE HAD BEEN WAITING TO TKOF FROM RWY 29 FOR ABOUT 3 MINS, ON THE RWY IN A HOLD POS. THE TWR APPROVED TKOF APPROX 10-15 SECS AFTER THE OTHER ACFT LIFTED OFF THE RWY. OTHER ACFT'S RADIO WAS INTERMITTENT. I WAS DOING THE RADIO COMS FOR BOTH ACFT. I WAS ADVISED TO PHONE THE TWR ASAP. THE PROB WAS ENHANCED BY THE OTHER PLT'S RADIO. THIS RADIO BECAME INTERMITTENT AS WE WERE PREPARING FOR TKOF. WE HAD AGREED THAT I WOULD DO THE RADIO COMS WITH THE TWR AS A FLT OF 2. I HAD NOT ADVISED THE TWR OF THE RADIO PROB. I BELIEVE THAT I SHOULD HAVE ADVISED THE TWR OF THE RADIO PROB AND ASK FOR A LIGHT SIGNAL FOR TKOF CLRNC.

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.