Narrative:

Routine VFR flight made for state of illinois inspection work of potential heliport sites in the joliet area. Flight was made under the chicago TCA 22 NM southwest of O'hare. I was not aware that the aircraft was not equipped with mode C until an inquiry was made to the maintenance department after the flight, because ATC at spi said they were not receiving an altitude readout on the aircraft. I was under the mistaken impression that all our aircraft had mode C installed prior to the july 89 deadline for operation within 30 NM of a TCA. The lesson I learned (obviously not too well) from this and another maintenance related incident not 2 weeks ago, is to check all aircraft maintenance and equipment personally and not put blind faith in others to do my checking.

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Original NASA ASRS Text

Title: ACFT NOT EQUIPPED WITH MODE C TRANSPONDER TO COMPLY WITH NEW RULING OF MODE C REQUIRED WITHIN 30 MILES OF A TCA.

Narrative: ROUTINE VFR FLT MADE FOR STATE OF ILLINOIS INSPECTION WORK OF POTENTIAL HELIPORT SITES IN THE JOLIET AREA. FLT WAS MADE UNDER THE CHICAGO TCA 22 NM SW OF O'HARE. I WAS NOT AWARE THAT THE ACFT WAS NOT EQUIPPED WITH MODE C UNTIL AN INQUIRY WAS MADE TO THE MAINT DEPT AFTER THE FLT, BECAUSE ATC AT SPI SAID THEY WERE NOT RECEIVING AN ALT READOUT ON THE ACFT. I WAS UNDER THE MISTAKEN IMPRESSION THAT ALL OUR ACFT HAD MODE C INSTALLED PRIOR TO THE JULY 89 DEADLINE FOR OPERATION WITHIN 30 NM OF A TCA. THE LESSON I LEARNED (OBVIOUSLY NOT TOO WELL) FROM THIS AND ANOTHER MAINT RELATED INCIDENT NOT 2 WEEKS AGO, IS TO CHECK ALL ACFT MAINT AND EQUIPMENT PERSONALLY AND NOT PUT BLIND FAITH IN OTHERS TO DO MY CHECKING.

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.