Tail inspection panel

[rodsmith]

I would like to see what others have done for inspection panels at the tail, pictures would be great. At the front stab attach I am thinking make an aluminum ring similar size to the plastic inspection plate rings, and a slotted cover so it can be slid off. I want to be able to change the stab incidence angle if test flying indicates it. The rear panel needs to extend above and below the longeron and the cover needs to be in two pieces. I'm thinking having one on both sides will make attaching the elevator and trim cables much easier.

[whee]

Here is was we did; it is a pretty good example of what NOT to do.



I haven't made the covers yet but the cover for the front stab attach will be two overlapping pieces which I think will look better than a single slotted piece. Also possible to hide the slot with the stab fairing. I wish we had made these access panels 1" larger in diameter. Rings are made of 0.032 2024 which we cut out on a wood lathe.

We don't have the factory style BH trim system so our rear access panel did not need to be as big. It is pretty tight but is big enough.

Also put a access on the lower left side to access the tail spring bolt.

]

Make your panels plenty big. I was trying to keep our plane looking clean and sleek but now regret making the access panels so small.

[interstate al]

Nice pics and your fabric work looks great Whee!

[Ray Strickland]

Rodsmith, I followed much the same thought process as you did. I glued an aluminum sheet perimeter ring to the inside of each opening and folded and glued the fabric over the rings. The rear rings have nutplates installed. For the front I used sheet metal screws. The rear covers are two-pieced. The front covers are slotted, but the slot is covered by the stab root fairing.

[jaredyates]

I was just making an incidence adjustment yesterday and found that the standard inspection ring is smaller than I'd really like for the leading edge attachment of the horizontal stab. I was able to get it done, but it took some fiddling. An incidence change requires changing out the spacer but also changing out the bolt, and the latter was the most difficult. My opening at the trailing edge looks a lot like Ray's in the previous post. In some places I embedded plastic reinforcing rings, which are fine when a round inspection plate is held in place with the spring, but for anything involving rivets or screws, an aluminum reinforcement is a must. Drilling a hole in the plastic ring makes the ring very weak at that spot. For something I don't expect to open on condition inspections, I use soft all aluminum pop rivets.They are easy to drill if the need arises.

[Ray Strickland]

More photos.

[rodsmith]

Thanks for the replies and photos. Jared that is good information on the front opening, I will make mine a little larger than the standard plastic ring. Time to get busy with the fly cutter. Great looking plane Ray!

[Ray Strickland]

Thank you.

[jaredyates]

[stinger]

Several of you have done the same I guess. I always go with KISS. Stinger

[Flygirl1]

We cut our own ring with a Malco hole cutter. You put it in your drill or drill press and set it to the size you want and cut holes, or covers or whatever you want. Then we match drilled the cover to the ring and put riv nuts in the ring and glued the ring to the fabric and put fabric tape over that and then used a wood burning tool to burn out the holes the fabric was covering. Then we beveled the edge of the cover slightly and cut it in half, or close to it and made the cuts to fit around the horizontal tubes. The horizontal fairing covers it all up nicely so you don’t see any of those cuts. We may have attached the riv nuts after we glued the ring to the fabric, can't remember but the riv nuts work great for this job.

[Battson]

I put in a large "armhole" and I am very happy I did.
Maintenance would never be easy without it, it is my go-to access panel for tailwheel main bolt tightening / changes, access to the electric trim (never needed any work so far), and general inspection of the internals in the aft fuselage.

[Rollie]

I wanted easy access for connecting everything. For stab forward mount I put rings on there but didn't cut the holes. If I need access at some point it will be easy to just cut and add a cover at that time.