Narrative:

Aircraft #1 approaching from southwest (from eastern tn), contacted tower 12 mi out, again at 5 mi. Tower cleared aircraft to 'left base to runway 34,' confirmed by pilot. As pilot #1 was approaching the extended centerline of runway 3 I heard tower clear aircraft #2 to land on runway 3. Alarmed, because I had no idea where the aircraft was since it had not called before. I leaned sharply forward, looked up and right and saw it coming straight toward a collision course. I said something like 'look out' into the microphone at the same time I dove and turned right. Aircraft #2 climbed and turned right. We both then continued on our cleared approachs. The tower controller yelled at me 'I thought I cleared you to a left base for runway 34!' I reported 'I am on a left base for runway 34!' I approached runway 34 and asked for clearance to land which was denied. There were no other aircraft in the air nor on the runways. I then asked the tower controller what he now wanted me to do and continued on a heading of about 070 degrees or 060 degrees. He then said 'cleared to land runway 34' and I landed. Several people on the ground heard the radio xmissions including the flight school director and a man in the office of the tower building. I am still trying to get the name of the controller. He must have had some kind of spatial disorientation and not realized that his clrncs put the 2 aircraft on a collision course which was only avoided by my awareness of its possibility.

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Original NASA ASRS Text

Title: HLG LCL CTLR INSTRUCTED TFC TO ENTER A L BASE BUT APPARENTLY MEANT A R BASE.

Narrative: ACFT #1 APCHING FROM SW (FROM EASTERN TN), CONTACTED TWR 12 MI OUT, AGAIN AT 5 MI. TWR CLRED ACFT TO 'L BASE TO RWY 34,' CONFIRMED BY PLT. AS PLT #1 WAS APCHING THE EXTENDED CTRLINE OF RWY 3 I HEARD TWR CLR ACFT #2 TO LAND ON RWY 3. ALARMED, BECAUSE I HAD NO IDEA WHERE THE ACFT WAS SINCE IT HAD NOT CALLED BEFORE. I LEANED SHARPLY FORWARD, LOOKED UP AND R AND SAW IT COMING STRAIGHT TOWARD A COLLISION COURSE. I SAID SOMETHING LIKE 'LOOK OUT' INTO THE MIKE AT THE SAME TIME I DOVE AND TURNED R. ACFT #2 CLBED AND TURNED R. WE BOTH THEN CONTINUED ON OUR CLRED APCHS. THE TWR CTLR YELLED AT ME 'I THOUGHT I CLRED YOU TO A L BASE FOR RWY 34!' I RPTED 'I AM ON A L BASE FOR RWY 34!' I APCHED RWY 34 AND ASKED FOR CLRNC TO LAND WHICH WAS DENIED. THERE WERE NO OTHER ACFT IN THE AIR NOR ON THE RWYS. I THEN ASKED THE TWR CTLR WHAT HE NOW WANTED ME TO DO AND CONTINUED ON A HEADING OF ABOUT 070 DEGS OR 060 DEGS. HE THEN SAID 'CLRED TO LAND RWY 34' AND I LANDED. SEVERAL PEOPLE ON THE GND HEARD THE RADIO XMISSIONS INCLUDING THE FLT SCHOOL DIRECTOR AND A MAN IN THE OFFICE OF THE TWR BUILDING. I AM STILL TRYING TO GET THE NAME OF THE CTLR. HE MUST HAVE HAD SOME KIND OF SPATIAL DISORIENTATION AND NOT REALIZED THAT HIS CLRNCS PUT THE 2 ACFT ON A COLLISION COURSE WHICH WAS ONLY AVOIDED BY MY AWARENESS OF ITS POSSIBILITY.

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.