Narrative:

Having rented an small aircraft for a business trip from reid-hillview airport in san jose, I departed nb over calaveras reservoir toward sunol intersection to proceed eb. I had been assured by the owner of the flying school where I am taking my instrument training, and from which I rented the plane, that said school's planes were fully equipped and meticulously maintained. I had no reason to suspect otherwise, as I had seen numerous daily training flts follow the same route. The trip was uneventful for me, but upon my return, I learned that the plane I was flying did not have mode C. During the trip I entered the 30 mi buffer zone of the san francisco TCA. Similarly equipped aircraft continue to follow the route described, but do so at an altitude which places them below the ridgeline of the hills immediately west. I presume the radar antenna is on the other side of the hills and that the aircraft are therefore not visible to the controllers. I am certain that this event went unnoticed, however, other trusting individuals ought to note well that one cannot believe what one is told by a flight school which is no doubt under pressure to keep as many planes in the air as possible, regardless of their actual condition. The TCA buffer zone starts slightly over 1 mi from the departure end of the northwest runways. That this flight school/FBO continues to operate aircraft without mode C surely defies reason.

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Original NASA ASRS Text

Title: GA SMA UNAUTH PENETRATION OF AIRSPACE.

Narrative: HAVING RENTED AN SMA FOR A BUSINESS TRIP FROM REID-HILLVIEW ARPT IN SAN JOSE, I DEPARTED NB OVER CALAVERAS RESERVOIR TOWARD SUNOL INTXN TO PROCEED EB. I HAD BEEN ASSURED BY THE OWNER OF THE FLYING SCHOOL WHERE I AM TAKING MY INSTRUMENT TRAINING, AND FROM WHICH I RENTED THE PLANE, THAT SAID SCHOOL'S PLANES WERE FULLY EQUIPPED AND METICULOUSLY MAINTAINED. I HAD NO REASON TO SUSPECT OTHERWISE, AS I HAD SEEN NUMEROUS DAILY TRAINING FLTS FOLLOW THE SAME ROUTE. THE TRIP WAS UNEVENTFUL FOR ME, BUT UPON MY RETURN, I LEARNED THAT THE PLANE I WAS FLYING DID NOT HAVE MODE C. DURING THE TRIP I ENTERED THE 30 MI BUFFER ZONE OF THE SAN FRANCISCO TCA. SIMILARLY EQUIPPED ACFT CONTINUE TO FOLLOW THE ROUTE DESCRIBED, BUT DO SO AT AN ALT WHICH PLACES THEM BELOW THE RIDGELINE OF THE HILLS IMMEDIATELY WEST. I PRESUME THE RADAR ANTENNA IS ON THE OTHER SIDE OF THE HILLS AND THAT THE ACFT ARE THEREFORE NOT VISIBLE TO THE CTLRS. I AM CERTAIN THAT THIS EVENT WENT UNNOTICED, HOWEVER, OTHER TRUSTING INDIVIDUALS OUGHT TO NOTE WELL THAT ONE CANNOT BELIEVE WHAT ONE IS TOLD BY A FLT SCHOOL WHICH IS NO DOUBT UNDER PRESSURE TO KEEP AS MANY PLANES IN THE AIR AS POSSIBLE, REGARDLESS OF THEIR ACTUAL CONDITION. THE TCA BUFFER ZONE STARTS SLIGHTLY OVER 1 MI FROM THE DEP END OF THE NW RWYS. THAT THIS FLT SCHOOL/FBO CONTINUES TO OPERATE ACFT WITHOUT MODE C SURELY DEFIES REASON.

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.