A typical Cessna Cardinal carry through spar eddy current inspection, part of the carry through AD.

A quick look at a typical process used to do the eddy current inspection required as one of the steps in the recent FAA airworthiness directive on the spar carry through.
For more information please visit cardinalflyers.com

[@hughboyle]

Nice job Keith. Helped take some of the mystery out of it.

[@gendaminoru3195]

You probably know this, but why did Cessna chose to rout the fuel tank vents all the way to their opposite sides? Think I saw the lines exposed there. Thanks for being THE guru of Cardinals

[@cardinalflyer]

The question to ponder is what will happen if a Cardinal is parked on a side slope? If a tank is vented out its own wingtip, that wingtip could become the lowest point in the fuel system and let all the fuel out. But crossing the vents over the top they avoid that issue. It took them a couple of years to come to this conclusion... the early year or two didn't do it that way. This led to the POH requirement to always select the right tank when parking... those years were designed to have minimum risk in that setting.

[@177flyer3]

Hello Keith, it seems the spar still has its anti corrosion paint on it. There was no need to remove it before inspection?

[@cardinalflyer]

Are you referring to the Corban or the Alodyne? The Alodyne stayed on through the whole process. There was no need to remove the CorBan for inspection, but I could not put the epoxy on over the CorBan. So the Corban needed to come off just to get the layers into the proper order.

[@Roboliver712]

The AD requires cleaning inspection for corrosion metal prep alidine eddy current then zinc chromate. It looks like your spar has already been treated and painted. So to tell pilots it's no big deal at 200 dollars is misleading them . Someone has spent alot of time on that spar.

[@cardinalflyer]

You seem to have misunderstood on several counts. The coatings preferred by the AD are epoxy primer and Corban... zinc chromate is an option but not preferred, and that's not the last coat. Also, Alodine is only required if not already done. At the time of this video my spar was still as original, although with Corban applied during one of the SEL stages. No one had spent time cleaning or alodining.... that's how it has been for some 50 some years. After this video I cleaned off the Corban, epoxy primed then re-applied Corban, along with paperwork as mentioned. As for misleading, I clearly said this was inspection was done of part of the overall process. In my case this was the only portion which required writing a check, but most other people won't be in a position to avoid hiring some of the work done or buying materials for the process. Check out my video about the headliner removal for more information on the overall process. kzbin.info/www/bejne/nZSrZoSMqp6lnqs As for whether it's a big deal, that will depend on what they find!

[@Roboliver712]

I was sent your video from a pilot who now believes his AD inspection should only cost 200 dollars. His spar was in bad shape and required a lot of work. I told him you probably had the SIL done first leaving only the eddy current inspection.

[@n5407c]

How often is this required?

[@cardinalflyer]

So far just once, for the 2023 AD.

[@Roboliver712]

The old aircraft spars don't look like yours. They where bare aluminium. We spent a day buffing the spar and it is nowhere as nice as yours. Doesn't the AD still ask you to prime the spare with zinc chromate. You only did the eddy current.

[@cardinalflyer]

How may times are you going to make the same general comment? You are incorrect on several levels here... you would do well to not try to mislead people! Read my answer to your last comment for specific answers.