Narrative:

Descended from 10500 ft MSL to land, after conducting maintenance flight test. Cavu WX conditions. Utilizing radar service, using visual scan, observed cessna T310R approaching head on at 12 O'clock position with estimated 400+ KT closure speed combined. Initiated evasive coordinated 50 degree left bank. Advised ATC of near miss. They confirmed primary only target at my 6 O'clock position eastbound. Advised target 'wasn't squawking or talking' by ATC. Target heading 090 degrees. My heading was 270 degrees. ATC advised that occurrences such as this warrant class C (TRSA) for waco. I advised ATC I would be filing NASA report. Controller advised he would also. The other pilot was an idiot. I don't think he ever saw me. He was eastbound cruising at 5000 ft MSL, an IFR altitude, with an inoperative or 'off' transponder. The entire event, from the time I initially saw him and I was close enough to tell he was a male, until he was past me, was 3 seconds. It was a white with yellow and brown stripes cessna T310R (long nose) paint scheme. This is as close as I have ever come to dying in an airplane. I was terrified. The waco area needs to be class C airspace. I was extremely lucky.

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Original NASA ASRS Text

Title: CPR PLT IN AN SMT TWIN ACFT AT ACT SPOTS A C310 HEAD-ON AND BANKS SHARPLY TO AVOID A COLLISION.

Narrative: DSNDED FROM 10500 FT MSL TO LAND, AFTER CONDUCTING MAINT FLT TEST. CAVU WX CONDITIONS. UTILIZING RADAR SVC, USING VISUAL SCAN, OBSERVED CESSNA T310R APCHING HEAD ON AT 12 O'CLOCK POS WITH ESTIMATED 400+ KT CLOSURE SPD COMBINED. INITIATED EVASIVE COORDINATED 50 DEG L BANK. ADVISED ATC OF NEAR MISS. THEY CONFIRMED PRIMARY ONLY TARGET AT MY 6 O'CLOCK POS EBOUND. ADVISED TARGET 'WASN'T SQUAWKING OR TALKING' BY ATC. TARGET HDG 090 DEGS. MY HDG WAS 270 DEGS. ATC ADVISED THAT OCCURRENCES SUCH AS THIS WARRANT CLASS C (TRSA) FOR WACO. I ADVISED ATC I WOULD BE FILING NASA RPT. CTLR ADVISED HE WOULD ALSO. THE OTHER PLT WAS AN IDIOT. I DON'T THINK HE EVER SAW ME. HE WAS EBOUND CRUISING AT 5000 FT MSL, AN IFR ALT, WITH AN INOP OR 'OFF' XPONDER. THE ENTIRE EVENT, FROM THE TIME I INITIALLY SAW HIM AND I WAS CLOSE ENOUGH TO TELL HE WAS A MALE, UNTIL HE WAS PAST ME, WAS 3 SECONDS. IT WAS A WHITE WITH YELLOW AND BROWN STRIPES CESSNA T310R (LONG NOSE) PAINT SCHEME. THIS IS AS CLOSE AS I HAVE EVER COME TO DYING IN AN AIRPLANE. I WAS TERRIFIED. THE WACO AREA NEEDS TO BE CLASS C AIRSPACE. I WAS EXTREMELY LUCKY.

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.