I started working on the cowling installation today. Earlier this week I began studying the drawings related to the cowling and had a bit of a shock, it seems my old plans have let me down again. The previous plan owner received the first drawings over 15 years ago hence some revisions have happened since then. I have been using the Sonex published revision list to make sure I'm all up to date but now I have noticed for the second time a revision that has been made to the plans but has not been published in the revision list: The installation of the cowling begins with installing a couple of piano hinge half's at the bottom of the firewall. I made the hinge half's and looked at installing them only to find out there is no way I could drill the outer 3 holes on the hinges because the motor mount is in the way. I then noticed on drawing P13 a producibility change that says this installation was moved to drawing F11 (firewall installation) in 2002. My P13 drawing is rather new but my F11 drawing is one of the original ones and it does not have the revision included. Because the revision list does not include it either I missed this one. I now had to think about what to do There was no way I could drill the outer 3 holes from the outside. Worst case I had to remove the engine and motor mount but I really did not want to do that.
Anyway, in the end it was not all that bad, I was able to drill most holes from the outside, then move the hinge to the inside of the firewall and cleco it in place to use as a template to drill the outer 3 holes from the inside. It just took a bit of time and required me to duck down head first under the panel and fuel tank. I will not be able to install those outer rivets from the outside either, they'll need to go in from the inside as well, but that does not bother me.
