Narrative:

While climbing to a cruise altitude of 7500 ft MSL, after departing lse on a heading of 100 degrees, VFR en route to osh via dll, I became aware of another mooney passing behind me on a northerly heading. Upon seeing the mooney I rocked my wings to acknowledge visual contact. My altimeter was indicating 5600 ft and climbing, my airspeed was 100 KTS. There were scattered clouds about 10 mi to the south of me and my path was clear. I couldn't understand why he didn't see me as I was broadside to his field of vision. And if he were IFR then center would inform him of my position as my transponder was squawking 1200 with mode C on. This incident is causing me to install a tcasi unit in my mooney. I was relaxed and looking for military aircraft to the northeast so my scan to the south was not what it should have been.

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Original NASA ASRS Text

Title: PLT IN MOONEY ACFT ON EASTERLY HDG AFTER DEPARTING LSE ARPT OBSERVES ANOTHER MOONEY PASS CLOSE BY ON A NORTHERLY HDG.

Narrative: WHILE CLBING TO A CRUISE ALT OF 7500 FT MSL, AFTER DEPARTING LSE ON A HDG OF 100 DEGS, VFR EN RTE TO OSH VIA DLL, I BECAME AWARE OF ANOTHER MOONEY PASSING BEHIND ME ON A NORTHERLY HDG. UPON SEEING THE MOONEY I ROCKED MY WINGS TO ACKNOWLEDGE VISUAL CONTACT. MY ALTIMETER WAS INDICATING 5600 FT AND CLBING, MY AIRSPD WAS 100 KTS. THERE WERE SCATTERED CLOUDS ABOUT 10 MI TO THE S OF ME AND MY PATH WAS CLR. I COULDN'T UNDERSTAND WHY HE DIDN'T SEE ME AS I WAS BROADSIDE TO HIS FIELD OF VISION. AND IF HE WERE IFR THEN CTR WOULD INFORM HIM OF MY POS AS MY XPONDER WAS SQUAWKING 1200 WITH MODE C ON. THIS INCIDENT IS CAUSING ME TO INSTALL A TCASI UNIT IN MY MOONEY. I WAS RELAXED AND LOOKING FOR MIL ACFT TO THE NE SO MY SCAN TO THE S WAS NOT WHAT IT SHOULD HAVE BEEN.

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.