Installing gear fairing with wings off, 7A

[Jekyll]

I searched but, didn't find what I was looking for. I'm finishing my build and thought I would do the gear fairings in my garage before I go to the paint booth. My question is whether or not I can install my intersection fairings with the wings off? I have Fairing Etc. upper and lowers and a 7A.

I held the top fairings up to the belly and it looks like I should be able to install and align them using just the bottom skin that extends out past the fuselage; the molded lip on the fairing snuggles nicely into position. I'll need to make a stand to raise and level the back of the plane while using an engine hoist to lift the front. I recognize I may need to do some final fitting after I install the wings but, I can easily repaint the upper fairings afterwards, if necessary.

Have others done it this way?

Am I missing something (besides the wings)?

Jekyll
7A

[mcencula]

If my friend, Tom's, RV-7A is typical, I believe the answer is no. Here's a photo of his left intersection fairing. You can see it overlaps the gap seal and wing fairing slightly.

[Captain Avgas]

Originally Posted by Jekyll

I searched but, didn't find what I was looking for. I'm finishing my build and thought I would do the gear fairings in my garage before I go to the paint booth. My question is whether or not I can install my intersection fairings with the wings off? I have Fairing Etc. upper and lowers and a 7A.

I held the top fairings up to the belly and it looks like I should be able to install and align them using just the bottom skin that extends out past the fuselage; the molded lip on the fairing snuggles nicely into position. I'll need to make a stand to raise and level the back of the plane while using an engine hoist to lift the front. I recognize I may need to do some final fitting after I install the wings but, I can easily repaint the upper fairings afterwards, if necessary.

Have others done it this way?

Am I missing something (besides the wings)?

Jekyll
7A

Whatever you do my suggestion would be to NOT instal the Fairings Etc top intersection fairing until you have properly aligned the gear leg fairing. I suspect that many builders who use the Fairings Etc intersection fairings instal the top fairing first to best fuselage fit and then that dictates the rotational orientation of the gear leg fairing.

However the best fit of the Fairings Etc upper intersection fairing to the fuselage (with the lip "snuggled" into position as you put it) may dictate that the gear leg fairing is not optimally orientated to eliminate assymetrical drag.

In other words the orientation of the gear leg fairing should dictate the orientation of the upper intersection fairing (not the other way around).

Vans has stated that a misalignment of only 1/4" in the trailing edge of the gear leg fairing can result in a half scale displacement of the skid ball. Assymetrical drag of that nature probably accounts for many reports of "heavy wing" in flight.

Personally, I'd align and instal the gear leg fairing and the lower intersection fairing (to the wheel fairing) and then wait until the wing was installed to locate the upper fairing. The idea would be to assure that the instalation of the upper fairing did not induce any twist into the gear leg fairing.

[docskj]

One of the smarter things I did in construction of my 9A was to do everything possible at home in my shop with good lighting, tools, and a relatively clean floor. The gear fairings require hours laying on the floor, lots of string lines, lasers, and drawing countless marks on the floor.

It is true you cannot do the final upper main gear intersection fairings until the wing is on as the screws penetrate the bottom wing skin in addition to the fuselage belly. The alignment of the gear intersection fairings is totally dependent on the correct alignment of the gear leg fairings. In fact, the upper intersection fairings "lock in" the leg fairings on the top end.

What I did was to get everything aligned just right, put the upper intersection fairings on and drill 3 small pilot holes for clecos into the fuselage to serve as the alignment holes. These were later drilled to full size for the nutplates once the wings are on at the airport. You can then add any further holes and nutplates penetrating the lower wing skin. This resulted in minimal fuss and time laying on a dark and dirty hanger floor.