Why can't I find a tail number in the FAA registery? I'm reviewing my pilot logbook in preparation to move everything over to my EFB logbook. As part of that process, I have been looking up the various aircraft I've flown in the FAA registry to get details about those aircraft to make my log complete (my digital pilot logbook tracks more information on an aircraft than my paper logbook and I'd like to have the details for my own nostalgic purposes). 

One particular aircraft I flew in 2005, N7635A, is nowhere to be found. Clearly the plane existed - I flew it! And it's in my logbook 3 times complete with my CFI instructor's signatures in those entries, so he seems to have thought the plane existed as well.

When I look up N7635A, I get a Cessna 180 (circa 1960s). I never flew a 180 (seems like I would have noticed that since the rest of the fleet was made up of 2002 - 2004 Cessna 172SPs and they all had that new plane smell). https://registry.faa.gov/aircraftinquiry/NNum_Results.aspx?NNumbertxt=7635A

My first thought was maybe the FAA drops registration records if a plane leaves the country - but that Cessna 180 is deregistered because it was exported to Canada. Also, another plane I flew, N65460, is also deregistered but still has a record with the FAA: https://registry.faa.gov/aircraftinquiry/NNum_Results.aspx?NNumbertxt=65460

I have tried different combinations:


N7635A - 1960 Cessna 180 (wrong plane)
N763SA - 1979 Cessna 152 (wrong plane)
N7G35A - not valid
N7G3SA - not valid


N60432 is another mystery 172S in my logbook but that's from 2013 and I only have a single entry for that one.

Do I have a correct understanding of the FAA N-Number registry? Am I wrong to think it's a complete record of all FAA N-Number registrations (going back to at least 1960)?
I think wrong to believe N-numbers are not recycled.  The process has changed, but now we (owners) must register every two years (I think two years).  //see comment below, registration update is every 3 years and $5 which is background noise compared to an annual