Continuing the series of backing plates, this time for the COM1 antenna on the underside of the tailcone. A Comant CI-122 bent whip antenna will be placed here.
The layout of the antenna fits just right between two stiffeners near the center part of the tailcone. Here the rough plate is marked for initial drilling.
The initial drill of three holes was done inside the plane. Then the plate was moved to the outside to match drill first the holes for the antenna mount, finally the plate holding rivets.
Here the final hole pattern for the antenna mount.
Here’s how the plate looks clecoed back into position on the inside.
And finally … a view of the antenna mounting location from outside. As with the other plates, alodine and prime treatment will occur before final attachment.