Narrative:

I was being trained to fly a lake amphibian by an instructor who was from a different state. We entered class D airspace that was less than 2 yrs old. I used a unicom channel that was obsolete and didn't discover the correct channel until we were well within class D airspace. I didn't have the sectional in front of me and he didn't know it was class D airspace because he inadvertently grabbed a sectional that was expired although we had a current sectional in the aircraft. The unicom frequency we used was being monitored by the airport FBO but no one called me to let me know I was on the incorrect frequency. The tower was very helpful and understanding as well as courteous to me even as we were in his airspace (st cloud; mn).

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Original NASA ASRS Text

Title: LAKE LA-4 PLT ENTERS STC CLASS D AIRSPACE WITHOUT CLRNC.

Narrative: I WAS BEING TRAINED TO FLY A LAKE AMPHIBIAN BY AN INSTRUCTOR WHO WAS FROM A DIFFERENT STATE. WE ENTERED CLASS D AIRSPACE THAT WAS LESS THAN 2 YRS OLD. I USED A UNICOM CHANNEL THAT WAS OBSOLETE AND DIDN'T DISCOVER THE CORRECT CHANNEL UNTIL WE WERE WELL WITHIN CLASS D AIRSPACE. I DIDN'T HAVE THE SECTIONAL IN FRONT OF ME AND HE DIDN'T KNOW IT WAS CLASS D AIRSPACE BECAUSE HE INADVERTENTLY GRABBED A SECTIONAL THAT WAS EXPIRED ALTHOUGH WE HAD A CURRENT SECTIONAL IN THE ACFT. THE UNICOM FREQ WE USED WAS BEING MONITORED BY THE ARPT FBO BUT NO ONE CALLED ME TO LET ME KNOW I WAS ON THE INCORRECT FREQ. THE TWR WAS VERY HELPFUL AND UNDERSTANDING AS WELL AS COURTEOUS TO ME EVEN AS WE WERE IN HIS AIRSPACE (ST CLOUD; MN).

Data retrieved from NASA's ASRS site as of January 2009 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.