On Monday, September 9, 2019 at 5:33:06 AM UTC-7, Bob Youngblood wrote:
On Sunday, September 8, 2019 at 7:30:01 PM UTC-4, wrote:
I've been approached by an estate of a former club member who's glider is stored at my club. Its a 1978 PIK20-D. They have gone through his entire belongings and have not found any logbooks for the glider. Our club records indicate the glider has not flown since 2003. Its been at the club since at least 1998. We have gone through the plane and trailer and no logs. Its a certified aircraft and our local AI said there is a process to start a new log book after an inspection. The question I ask is how much value is lost with no history of the airframe? I'm trying to help the estate come up with a reasonable value.

Personally I would not bee too concerned about a lost log. You can start all over and create a new log going forward. A good inspection of the glider should allow you the ability to determine the overall condition and other variables. Don't give up on finding the logs. the old owner stashed them away and the family may just find them. It happened to me recently with a Pawnee, and I did get all the logs.
Discount the price a bit and move forward with a good inspection and enjoy that glider. Find the past couple of owners or someone who can give you details on how much the bird flew and try to determine approximate time.

This all depends upon what you mean by "a bit." I would suggest "a lot," like 50%.