Messed up the holes to attach the floor stiffeners to the F-704

[idubrov]

Originally Posted by sahrens

You are correct that is the mil-spec. Interestingly AC 43-13 states the minimum edge distance is 2D or in this case 0.250. It will be interesting to see which standard Vans recommends

Yes, this has been discussed many times. My understanding is that Vans uses MIL-R-47196A, which is both listed in the Chapter 5 and also given in their technical FAQ area. It's also my understanding that AC 43-13 is a generic recommendation that applies unless there are specific manufacturer recommendations.

Generally, my attitude is that I aim for 2D and verify with the MIL Spec.

[idubrov]

Okay, so the update:

1. The "short" edge distance on the stiffener is not a problem.
2. Countersinks for 1/8" are acceptable, since it's just a single location.
3. After drilling the aftmost hole that attaches the F-783B cover support rib, I found that this hole is even worse, this time it's definitely "out of spec" with the ~0.190" edge distance. Also, according to Van's support, not a problem.

So I think I'll go the simplest path and do it the way instructions say, but with a -4 rivet.

This is the edge distance from the third item above: