Narrative:

Proceeding nwbound on V94 at 8425 ft MSL, I was overtaken by a bonanza (straight tail type). Other aircraft appeared above me, in view exactly on my centerline, about 75 ft above. Because the horizontal separation was precisely zero, I never did see his registration number. He continued level above me, about 25 KTS faster than my cherokee-6- 300, and pulled away. I questioned -- ZAB with whom I was squawking a discrete code on flight following. Previously in the flight, in another sector, I had been alerted about overtaking traffic. They told me they were not showing any other traffic near me. At the time they said that, the bonanza was readily visible a mi or so ahead. Discovery earlier visually impossible in PA32-300 with no rear overhead window. Avoidance visually impossible for same reason. Discovery and avoidance only possible using TCASII (TCASII for small GA aircraft). I believe he was probably on autoplt with altitude hold. My altitude hold had misfunctioned and I was on heading autoplt only, flying altitude manually. Maybe its a good idea to fly near but not exactly on the chosen altitude. I wouldn't be here if I had.

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Original NASA ASRS Text

Title: NMAC BTWN 2 SMA SEL ACFT WHERE THE OTHER ACFT OVERTOOK THE RPTR DIRECTLY ABOVE BY 75 FT.

Narrative: PROCEEDING NWBOUND ON V94 AT 8425 FT MSL, I WAS OVERTAKEN BY A BONANZA (STRAIGHT TAIL TYPE). OTHER ACFT APPEARED ABOVE ME, IN VIEW EXACTLY ON MY CTRLINE, ABOUT 75 FT ABOVE. BECAUSE THE HORIZ SEPARATION WAS PRECISELY ZERO, I NEVER DID SEE HIS REGISTRATION NUMBER. HE CONTINUED LEVEL ABOVE ME, ABOUT 25 KTS FASTER THAN MY CHEROKEE-6- 300, AND PULLED AWAY. I QUESTIONED -- ZAB WITH WHOM I WAS SQUAWKING A DISCRETE CODE ON FLT FOLLOWING. PREVIOUSLY IN THE FLT, IN ANOTHER SECTOR, I HAD BEEN ALERTED ABOUT OVERTAKING TFC. THEY TOLD ME THEY WERE NOT SHOWING ANY OTHER TFC NEAR ME. AT THE TIME THEY SAID THAT, THE BONANZA WAS READILY VISIBLE A MI OR SO AHEAD. DISCOVERY EARLIER VISUALLY IMPOSSIBLE IN PA32-300 WITH NO REAR OVERHEAD WINDOW. AVOIDANCE VISUALLY IMPOSSIBLE FOR SAME REASON. DISCOVERY AND AVOIDANCE ONLY POSSIBLE USING TCASII (TCASII FOR SMALL GA ACFT). I BELIEVE HE WAS PROBABLY ON AUTOPLT WITH ALT HOLD. MY ALT HOLD HAD MISFUNCTIONED AND I WAS ON HDG AUTOPLT ONLY, FLYING ALT MANUALLY. MAYBE ITS A GOOD IDEA TO FLY NEAR BUT NOT EXACTLY ON THE CHOSEN ALT. I WOULDN'T BE HERE IF I HAD.

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.