Narrative:

I was working local control. I noticed aircraft X, a PA28, entering my airspace from the southwest. I called out to the aircraft with no response. I called the N90 sector to have them send the aircraft over. When the aircraft called it was on a close in left base. I told the aircraft to join downwind. Aircraft X asked me to turn up the lights, I told him there were other aircraft on final ahead of him, join the downwind and I would call his sequence. I noticed the aircraft continuing to descend and still on a base heading. I told aircraft X to go around and to climb immediately. I put aircraft X on a 020 degree heading and climbed him to 1500 ft. He missed a CL60, aircraft Y, by my estimate less than 100 ft vertically and horizontally. I have never seen 2 aircraft in such close proximity. Aircraft X returned for landing, said he had field in sight. I cleared him to land on runway 34 and he landed on runway 29. I allowed that to occur just to get aircraft X safely on the ground. ATCT management talked to the pilot of aircraft X. Management did not log the incident, did not call the regional communications center, did not fill out paperwork concerning near midair, pilot deviation or any incident reporting forms. The supervisor told me that he told aircraft X that he would have to wait to see if aircraft Y calls to see if any further action would be taken.

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Original NASA ASRS Text

Title: PIPER PLT ENTERS CLASS C AIRSPACE WITHOUT A HDOF FROM TRACON TO TWR WHICH REPORTEDLY RESULTS IN AN NMAC AND A WRONG RWY LNDG.

Narrative: I WAS WORKING LCL CTL. I NOTICED ACFT X, A PA28, ENTERING MY AIRSPACE FROM THE SW. I CALLED OUT TO THE ACFT WITH NO RESPONSE. I CALLED THE N90 SECTOR TO HAVE THEM SEND THE ACFT OVER. WHEN THE ACFT CALLED IT WAS ON A CLOSE IN L BASE. I TOLD THE ACFT TO JOIN DOWNWIND. ACFT X ASKED ME TO TURN UP THE LIGHTS, I TOLD HIM THERE WERE OTHER ACFT ON FINAL AHEAD OF HIM, JOIN THE DOWNWIND AND I WOULD CALL HIS SEQUENCE. I NOTICED THE ACFT CONTINUING TO DSND AND STILL ON A BASE HEADING. I TOLD ACFT X TO GO AROUND AND TO CLB IMMEDIATELY. I PUT ACFT X ON A 020 DEG HDG AND CLBED HIM TO 1500 FT. HE MISSED A CL60, ACFT Y, BY MY ESTIMATE LESS THAN 100 FT VERTLY AND HORIZLY. I HAVE NEVER SEEN 2 ACFT IN SUCH CLOSE PROX. ACFT X RETURNED FOR LNDG, SAID HE HAD FIELD IN SIGHT. I CLRED HIM TO LAND ON RWY 34 AND HE LANDED ON RWY 29. I ALLOWED THAT TO OCCUR JUST TO GET ACFT X SAFELY ON THE GND. ATCT MGMNT TALKED TO THE PLT OF ACFT X. MGMNT DID NOT LOG THE INCIDENT, DID NOT CALL THE REGIONAL COMS CTR, DID NOT FILL OUT PAPERWORK CONCERNING NEAR MIDAIR, PLTDEV OR ANY INCIDENT RPTING FORMS. THE SUPVR TOLD ME THAT HE TOLD ACFT X THAT HE WOULD HAVE TO WAIT TO SEE IF ACFT Y CALLS TO SEE IF ANY FURTHER ACTION WOULD BE TAKEN.

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.