I found out late that the RNCs were being deleted from NOAA site, so I have been trying to source them. Thanks so much for making the large repository available. I found a complete list of all RNC charts (cancelled or not) on the NOAA site and cross checked it against your collection. Here's what yours is missing: Lake Tahoe #18665 (which I have and can send to you), 15 charts from AK #16041 - 16082, and 17 charts from MN #14982 - 14998. Maybe this will help track them down...