Captain Avgas
Well Known Member
Vans calls for addition of relief notches
Step 8 of the relevant Service Bulletin reinforcement instructions states as follows:
"Inspect the corners at the inboard end of the top and bottom fwd spar flanges on the left and right spar halves for the presence of relief notches as depicted in Figure 3.
If notches are not present, use a round file to add relief notches (first refer to the following step... adding a missing notch may be done in conjunction with removing a crack). This will require trimming the skin slightly as shown in Figure 2 to gain access for the file".
I think that's your answer.
I think it also addresses concerns raised by a number of posters that the relief notches might in fact be precipitating the problem.
Rvbuilder2002,
Would you be willing to comment on the relief notches vs normal smoothed radius as it relates to FEA?
Step 8 of the relevant Service Bulletin reinforcement instructions states as follows:
"Inspect the corners at the inboard end of the top and bottom fwd spar flanges on the left and right spar halves for the presence of relief notches as depicted in Figure 3.
If notches are not present, use a round file to add relief notches (first refer to the following step... adding a missing notch may be done in conjunction with removing a crack). This will require trimming the skin slightly as shown in Figure 2 to gain access for the file".
I think that's your answer.
I think it also addresses concerns raised by a number of posters that the relief notches might in fact be precipitating the problem.
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