----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]----
Some time ago, I advocated using wing removal as the easiest method of complying with the center section AD. In my own case, I have done a number of wing removals, and felt that I could spot serious corrosion using this method. I had taken my own wings off for a mini restoration, and was of the opinion that I was free of all corrosion. Since I had taken the wings off before the effective date of the AD I didn't sign the AD off. I decided to install the inspection holes to allow inspection every annual. On the pilots side, rear inboard inspection hole I found the inner rib had a stiffener that was almost powder. The rib itself is fine at this time only the small stiffener is affected. In addition, there is some surface corrosion that will progress to pitting in the near future. This was NOT visible with the wings off. Had I not put the inspection holes in, the inner rib would require replacement in the future, and the surface corrosion would be much more difficult to control. This was my first installation of the inspection holes. I wanted to do it to my own plane first before I did it to anyone else's. I took me 4 hours for the job. This includes some very careful measuring since I have the ribbed skin and there isn't much room for the three inch holes. It also includes some OH S--T time spent contemplating the ugly stiffener. Also this was the first opening I cut, and I was half afraid to look in the next holes. <G> To pull the wings and reinstall them takes me 5 hours with help. The openings an hour less. After this eye opener, I would have to retract any advice I gave about wing removal, and say scope or openings is the way to go. In fact, if you wanted to do a really thorough job, wing removal AND openings. You can't get a look behind the tanks. or at the wing attach fittings with the inspection holes. As it stands, I have about 3-4 hours work to remove the corroded stiffener and make another plus clean up the surface stuff. Perhaps in 3 years I'd have an inner rib to replace--possibly more. If any of you Western Washington Coupers want the inspection holes, I'll be glad to help very reasonably. Cheers: Paul NC2273H ========================================================================== ==== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/
<<attachment: winmail.dat>>
