Narrative:

Event: failure to comply with ATC instructions. Aircraft: C150M. Chain of events: returning to ryan airport after a local flight, I contacted ryan tower for landing instructions. I was told to report entering right downwind for runway 24L. There were at least 3 other aircraft being directed by ryan ATC during this time. I turned downwind and reported my position, but ATC issued instructions to the 3 other aircraft before advising me of departing crosswind traffic. I realize now that my transmission was probably blocked and ATC did not receive my downwind report, but at the time I took the TA as an indication that the tower was aware of my position on downwind (first major mistake). I was approaching the point at which I normally begin to configure the airplane for landing and 'force of habit' took over. A few moments later I was rolling out on runway 24L and ryan tower was not at all pleased that I had landed without clearance (second even- more-major mistake). Human performance factors: very little recent flight time. I usually fly during times when the tower is closed or not very busy, so recent experience with ATC operations is limited. Pilot nearing saturation from trying to avoid unseen traffic and visualize the situation from ATC directives while setting-up for a landing. Assuming ATC had received my report and knew my position without explicit acknowledgment. Upon reaching a point in the situation with which I was very familiar (the actual setup for landing), my mind simply forgot about everything else and went into 'automatic landing mode.' remedies: correcting factors above are fairly obvious: fly more often and don't assume anything. Factor 5 is far more scary. I slipped into a state of mind without any realization that it was happening and didn't even realize what I had done until ATC made it abundantly clear. As far as I knew everything was just fine, same as it had been a thousand times before. I'm not at all sure how to correct this.

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Original NASA ASRS Text

Title: PLT OF C150 LANDS WITHOUT CLRNC. HE WAS GIVEN INSTRUCTIONS TO ENTER DOWNWIND AND RPTED BUT NEVER ISSUED LNDG CLRNC.

Narrative: EVENT: FAILURE TO COMPLY WITH ATC INSTRUCTIONS. ACFT: C150M. CHAIN OF EVENTS: RETURNING TO RYAN ARPT AFTER A LCL FLT, I CONTACTED RYAN TWR FOR LNDG INSTRUCTIONS. I WAS TOLD TO RPT ENTERING R DOWNWIND FOR RWY 24L. THERE WERE AT LEAST 3 OTHER ACFT BEING DIRECTED BY RYAN ATC DURING THIS TIME. I TURNED DOWNWIND AND RPTED MY POS, BUT ATC ISSUED INSTRUCTIONS TO THE 3 OTHER ACFT BEFORE ADVISING ME OF DEPARTING XWIND TFC. I REALIZE NOW THAT MY XMISSION WAS PROBABLY BLOCKED AND ATC DID NOT RECEIVE MY DOWNWIND RPT, BUT AT THE TIME I TOOK THE TA AS AN INDICATION THAT THE TWR WAS AWARE OF MY POS ON DOWNWIND (FIRST MAJOR MISTAKE). I WAS APCHING THE POINT AT WHICH I NORMALLY BEGIN TO CONFIGURE THE AIRPLANE FOR LNDG AND 'FORCE OF HABIT' TOOK OVER. A FEW MOMENTS LATER I WAS ROLLING OUT ON RWY 24L AND RYAN TWR WAS NOT AT ALL PLEASED THAT I HAD LANDED WITHOUT CLRNC (SECOND EVEN- MORE-MAJOR MISTAKE). HUMAN PERFORMANCE FACTORS: VERY LITTLE RECENT FLT TIME. I USUALLY FLY DURING TIMES WHEN THE TWR IS CLOSED OR NOT VERY BUSY, SO RECENT EXPERIENCE WITH ATC OPS IS LIMITED. PLT NEARING SATURATION FROM TRYING TO AVOID UNSEEN TFC AND VISUALIZE THE SIT FROM ATC DIRECTIVES WHILE SETTING-UP FOR A LNDG. ASSUMING ATC HAD RECEIVED MY RPT AND KNEW MY POS WITHOUT EXPLICIT ACKNOWLEDGMENT. UPON REACHING A POINT IN THE SIT WITH WHICH I WAS VERY FAMILIAR (THE ACTUAL SETUP FOR LNDG), MY MIND SIMPLY FORGOT ABOUT EVERYTHING ELSE AND WENT INTO 'AUTOMATIC LNDG MODE.' REMEDIES: CORRECTING FACTORS ABOVE ARE FAIRLY OBVIOUS: FLY MORE OFTEN AND DON'T ASSUME ANYTHING. FACTOR 5 IS FAR MORE SCARY. I SLIPPED INTO A STATE OF MIND WITHOUT ANY REALIZATION THAT IT WAS HAPPENING AND DIDN'T EVEN REALIZE WHAT I HAD DONE UNTIL ATC MADE IT ABUNDANTLY CLR. AS FAR AS I KNEW EVERYTHING WAS JUST FINE, SAME AS IT HAD BEEN A THOUSAND TIMES BEFORE. I'M NOT AT ALL SURE HOW TO CORRECT THIS.

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.