Narrative:

I was midway through a turn from left base to final for runway 29 at san jose international. I was cleared to land. I was at approximately 800 ft and an MD80 flew directly under my aircraft, with about 60-70 ft of vertical separation. I did not see the MD80 until it was below and to my left as I made my turn to final. It first appeared on a line which bisected the angle created between the leading edge of my left wing and the 'post' at the forward edge of my left front window. Background: I was the sole occupant of my aircraft. I was on a VFR flight. Departed palo alto with half moon bay as an initial destination, then to san jose international for some night lndgs. Upon climbing to 4500 ft and on the west side of the pacific coast range, I could see half moon bay was not VFR, so I turned southeast, climbed to 5500 ft until about 15 mi southwest of san jose. While level at 5500 ft I got san jose's ATIS, and contacted bay approach with a request inbound full stop at san jose international. I advised approach that I was unfamiliar with the airport. He had me descend to 3000 ft. When I was at about 3300 ft he had me descend to 2000 ft. San jose tower described an aiming point of 'the pruneyard' and I was cleared to land runway 29 and advised me of an MD80 on an 8 mi final. I didn't clearly hear which runway and asked 'say again' I had clearly heard the TA, and responded 'no joy.' san jose tower confirmed runway 29. I also indicated I wasn't familiar with the 'pruneyard.' tower then advised me to look for a single large building to the left of the downtown group of large buildings. Tower advised the MD80 of my aircraft at 10 O'clock position, 1 1/2 mi, to which he responded, 'we're looking.' tower further advised me of a departing B757 causing wake turbulence, wind 300 degrees at 6 KTS. Tower further advised the MD80 'your traffic is position and hold on runway 30.' to the best of my knowledge, that was the last transmission prior to the MD80 passing underneath my aircraft.

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Original NASA ASRS Text

Title: NMAC BTWN A PIPER PA28 TURNING FINAL FOR SJC RWY 29, AND A SUPER MD80 ON FINAL TO RWY 30L. THE PA28 HAD OVERSHOT RWY 29, WHICH WAS ONLY 500 FT FROM RWY 30L.

Narrative: I WAS MIDWAY THROUGH A TURN FROM L BASE TO FINAL FOR RWY 29 AT SAN JOSE INTL. I WAS CLRED TO LAND. I WAS AT APPROX 800 FT AND AN MD80 FLEW DIRECTLY UNDER MY ACFT, WITH ABOUT 60-70 FT OF VERT SEPARATION. I DID NOT SEE THE MD80 UNTIL IT WAS BELOW AND TO MY L AS I MADE MY TURN TO FINAL. IT FIRST APPEARED ON A LINE WHICH BISECTED THE ANGLE CREATED BTWN THE LEADING EDGE OF MY L WING AND THE 'POST' AT THE FORWARD EDGE OF MY L FRONT WINDOW. BACKGROUND: I WAS THE SOLE OCCUPANT OF MY ACFT. I WAS ON A VFR FLT. DEPARTED PALO ALTO WITH HALF MOON BAY AS AN INITIAL DEST, THEN TO SAN JOSE INTL FOR SOME NIGHT LNDGS. UPON CLBING TO 4500 FT AND ON THE W SIDE OF THE PACIFIC COAST RANGE, I COULD SEE HALF MOON BAY WAS NOT VFR, SO I TURNED SE, CLBED TO 5500 FT UNTIL ABOUT 15 MI SW OF SAN JOSE. WHILE LEVEL AT 5500 FT I GOT SAN JOSE'S ATIS, AND CONTACTED BAY APCH WITH A REQUEST INBOUND FULL STOP AT SAN JOSE INTL. I ADVISED APCH THAT I WAS UNFAMILIAR WITH THE ARPT. HE HAD ME DSND TO 3000 FT. WHEN I WAS AT ABOUT 3300 FT HE HAD ME DSND TO 2000 FT. SAN JOSE TWR DESCRIBED AN AIMING POINT OF 'THE PRUNEYARD' AND I WAS CLRED TO LAND RWY 29 AND ADVISED ME OF AN MD80 ON AN 8 MI FINAL. I DIDN'T CLRLY HEAR WHICH RWY AND ASKED 'SAY AGAIN' I HAD CLRLY HEARD THE TA, AND RESPONDED 'NO JOY.' SAN JOSE TWR CONFIRMED RWY 29. I ALSO INDICATED I WASN'T FAMILIAR WITH THE 'PRUNEYARD.' TWR THEN ADVISED ME TO LOOK FOR A SINGLE LARGE BUILDING TO THE L OF THE DOWNTOWN GROUP OF LARGE BUILDINGS. TWR ADVISED THE MD80 OF MY ACFT AT 10 O'CLOCK POS, 1 1/2 MI, TO WHICH HE RESPONDED, 'WE'RE LOOKING.' TWR FURTHER ADVISED ME OF A DEPARTING B757 CAUSING WAKE TURB, WIND 300 DEGS AT 6 KTS. TWR FURTHER ADVISED THE MD80 'YOUR TFC IS POS AND HOLD ON RWY 30.' TO THE BEST OF MY KNOWLEDGE, THAT WAS THE LAST XMISSION PRIOR TO THE MD80 PASSING UNDERNEATH MY 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.