Narrative:

I was approaching an uncontrolled airport (petaluma, ca.) at 1700 ft from the south for landing. The airport is 87 ft MSL and the pattern is 1087 ft MSL. I was going to overhead the airport and then turn left and descend into a 45 for a right downwind to runway 29. There are hills north of the field rising to about 1700-1800 ft. I called on the CTAF and observed planes in the pattern. As I was crossing what would have been a wide (but acceptable) downwind, I heard a beech duchess yelling about a cherokee's intentions. I quickly looked and saw him directly out my left side window. I looked at my altimeter and was amazed to see I was just over 1000 ft. I had just flown directly through the downwind leg of the pattern. There was some more yelling on the radio and by this time I was completely devastated by my stupidity. I try very hard to be a safe pilot and could not believe I had just done this. I am also very familiar with this airport. I think there were several factors leading up to this. I have been very concerned about my job and events had transpired earlier that day that were still weighing heavily on my mind. I also had the alternator trip off-line when I turned on the landing light, coming up over the field. I was thinking about this and deciding whether to reset it now (and lose communication capability) or wait till I was on the ground. I also think a contributing factor is that the windscreen is 'full of mountains' prior to making the turn, so the horizon is lost. My lack of recent flight experience didn't help either.

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Original NASA ASRS Text

Title: PLT OF PA28-180 DSNDING FOR A DOWNWIND PATTERN ENTRY FINDS HIMSELF AT PATTERN ALT AND ABEAM AN ACFT ON DOWNWIND WHO QUERIES HIM AS TO HIS INTENTIONS.

Narrative: I WAS APPROACHING AN UNCONTROLLED ARPT (PETALUMA, CA.) AT 1700 FT FROM THE S FOR LNDG. THE ARPT IS 87 FT MSL AND THE PATTERN IS 1087 FT MSL. I WAS GOING TO OVERHEAD THE AIRPORT AND THEN TURN L AND DSND INTO A 45 FOR A R DOWNWIND TO RWY 29. THERE ARE HILLS N OF THE FIELD RISING TO ABOUT 1700-1800 FT. I CALLED ON THE CTAF AND OBSERVED PLANES IN THE PATTERN. AS I WAS CROSSING WHAT WOULD HAVE BEEN A WIDE (BUT ACCEPTABLE) DOWNWIND, I HEARD A BEECH DUCHESS YELLING ABOUT A CHEROKEE'S INTENTIONS. I QUICKLY LOOKED AND SAW HIM DIRECTLY OUT MY L SIDE WINDOW. I LOOKED AT MY ALTIMETER AND WAS AMAZED TO SEE I WAS JUST OVER 1000 FT. I HAD JUST FLOWN DIRECTLY THROUGH THE DOWNWIND LEG OF THE PATTERN. THERE WAS SOME MORE YELLING ON THE RADIO AND BY THIS TIME I WAS COMPLETELY DEVASTATED BY MY STUPIDITY. I TRY VERY HARD TO BE A SAFE PLT AND COULD NOT BELIEVE I HAD JUST DONE THIS. I AM ALSO VERY FAMILIAR WITH THIS ARPT. I THINK THERE WERE SEVERAL FACTORS LEADING UP TO THIS. I HAVE BEEN VERY CONCERNED ABOUT MY JOB AND EVENTS HAD TRANSPIRED EARLIER THAT DAY THAT WERE STILL WEIGHING HEAVILY ON MY MIND. I ALSO HAD THE ALTERNATOR TRIP OFF-LINE WHEN I TURNED ON THE LNDG LIGHT, COMING UP OVER THE FIELD. I WAS THINKING ABOUT THIS AND DECIDING WHETHER TO RESET IT NOW (AND LOSE COM CAPABILITY) OR WAIT TILL I WAS ON THE GROUND. I ALSO THINK A CONTRIBUTING FACTOR IS THAT THE WINDSCREEN IS 'FULL OF MOUNTAINS' PRIOR TO MAKING THE TURN, SO THE HORIZON IS LOST. MY LACK OF RECENT FLT EXPERIENCE DIDN'T HELP EITHER.

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.