Narrative:

This occurred in the southern california special airspace corridor over lax. I was nwbound at 3500 ft. I inadvertently selected the wrong altitude. Should have been at 4500 ft. Other aircraft was at 4000 ft approximately, should have been at 3500 ft. I announced my entry to the corridor as 3500 ft and flew it. Did not hear the cessna. I think center should monitor frequency 128.55 and watch aircraft squawking 1201. Traffic is heavy and accidents could easily happen when people make an honest mistake.

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Original NASA ASRS Text

Title: PA32R TRANSITIONING THE LAX SPECIAL AIRSPACE CORRIDOR, FLEW NW AT 3500 FT, SHOULD BE 4500 FT. ENCOUNTERED C182 SEBOUND AT 4000 FT. NO EVASIVE TAKEN.

Narrative: THIS OCCURRED IN THE SOUTHERN CALIFORNIA SPECIAL AIRSPACE CORRIDOR OVER LAX. I WAS NWBOUND AT 3500 FT. I INADVERTENTLY SELECTED THE WRONG ALT. SHOULD HAVE BEEN AT 4500 FT. OTHER ACFT WAS AT 4000 FT APPROX, SHOULD HAVE BEEN AT 3500 FT. I ANNOUNCED MY ENTRY TO THE CORRIDOR AS 3500 FT AND FLEW IT. DID NOT HEAR THE CESSNA. I THINK CTR SHOULD MONITOR FREQ 128.55 AND WATCH ACFT SQUAWKING 1201. TFC IS HVY AND ACCIDENTS COULD EASILY HAPPEN WHEN PEOPLE MAKE AN HONEST MISTAKE.

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.