On Sun, 09 Sep 2007 13:06:21 GMT, Michael Bushey
wrote:

My 15 year old boat has black patches on the indoor outdoor carpet. It
appears to be old mildew. Vinegar and baking soda didn't touch it. Carpet
cleaner doesn't work. Any suggestions appreciated.

The traditional remedy for mildew is chlorine bleach. It works but
will probably leave you with blotchy coloration. After 15 years it
may be time to replace the carpet.