Glad you asked that....good excuse to direct you to Jack Bales site which has a 78",1/16th scale PBY (and a lot of other interesting aircraft, including oddities). I think that Mr Bale may not be with us any more but a relation is continuing to keep the plans available. Try an email to
jackbale@dreamsoft.com The website is
http://web.dreamsoft.com/jackbale/home.htm There are numerous kits available of course from other sources.