A DAN Adventure

[Colin]

Do you mean the crack in the gel coat? Can you just wipe off the grease and cover that with some touch up paint?

[mhoran]

I didn't look to closely, I was too frustrated that our governor is still leaking after three weeks downtime to supposedly fix it (on top of the previous three weeks to "fix" the same issue). But the crack seemed to be more than just the gel coat. The shop deemed it airworthy though.

[Rich]

Not to be alarmist, but it looks like it might be a crack in the seam between the fuselage and the bulkhead to which the rudder is attached. I'd definitely look real closely at that.

[mhoran]

It does look pretty bad. It's definitely worse than when I brought it in. Which means that either happened when they reattached or in flight.

Here's a before photo:

[mhoran]

Performed a more thorough inspection today with Jim Markey of Take Flight, who initially discovered this. Looks like it is just a crack in the paint as Colin suggested. But I will have a more thorough inspection performed next annual (May).

[jwx96]

Thanks for the report and the photos showing the rudder attachment area and hardware. Something to look at in more detail during preflights.

[Steve]

In the midst of my Annual Inspection. Removed the rudder today, this is what the attachment area on mine looks like:

Rudder attachment area

There is a metal doubler inside the rudder that the attachment studs are fixed to. The edge of the doubler is in the area where your crack is. I would be very nervous about this. I am always careful to check the two Nyloc nuts that attach the rudder to the lower pivot. I have never agreed on the use of Nylocs in an area with this level of criticality. I would have preferred castellated nuts with cotter pins, as are used in the trim tab friction damper assembly and the nose gear axle shaft. Any failure in the rudder attachment could lead to loss of the aircraft.

Matt: Did you look inside the rudder with a borescope?

[mhoran]

Thanks Steve, that's very helpful. We are fairly positive that the crack does not go through the composite. Looking very closely, the material is intact on the front side and the crack does appear only to be in the paint. There is no crack that can be felt on the rear side.

I'm not sure if they borescoped, but I'll be going back in a week or so when I get a replacement governor to try and stop the learking, and we can check it out then.

I'm scheduled to bring the plane to SouthTec in December to repair the rudder regardless.

[Rich]

I would have preferred castellated nuts with cotter pins, as are used in the trim tab friction damper assembly and the nose gear axle shaft.

Both of those are self-locking on my aircraft, as are many others.

[Steve]

Sounds like a plan. I know that the gel coat can crack with a completely intact structure underneath. In fact, my airplane has a 8 inch long crack where the left rear wing root extension meets the fuselage. Luckily, this area is easy to examine directly from below, and there is no crack in the composite. This crack appeared about a year into ownership (so 21 years ago) and has not changed since then. I sent photos to DAI and they stated that it was not an issue...