Oratex Drain Vent Holes

[Greg79]

Where and how many drain holes should be put in? I have covered everything but my wings and had not thought about drain holes just inspection holes. Thanks!

[PapuaPilot]

Basically you want one at any low point where water could gather. For wings you want a drain hole in every rib bay at the inboard aft corner. I put two on each elevator, rudder and horizontal stabilizers. I can't remember how many are on the fuselage bottom, but you want one as far back as possible near the tailwheel mount area.

Like DenaliFox said, seaplane grommets create suction and will draw out the moisture and humidity. That's why I like them and recommend their use over the flat washers.

[alexM]

Where and how many drain holes should be put in? I have covered everything but my wings and had not thought about drain holes just inspection holes. Thanks!

Thanks for asking that, and thanks to Phil for the answer.

I'm finally covering my wings now so I could use all the idiot proof instructions I can get.

[Denalifox]

i did every rib bay in the wings and lowest points in the drooping elevator and rudder. Beauty of Oratex is you just poke a hole and glue whatever grommet of your choosing to the spot and you are done. I would not just poke holes (cauterized or not) without some form of reinforcement (that being a grommet). The amount of drain holes sort of depends on your area. Up here having water in your airplane is near impossible to avoid. So water mitigation is more the name of the game here. After figuring out all my little hidden spots water liked to creep I have yet to have any issues. Another thing to note, Water doesnt effect Oratex glue nor does subzero temps. Not a single issue through out the winter.

[alexM]

Where and how many drain holes should be put in? I have covered everything but my wings and had not thought about drain holes just inspection holes. Thanks!

On the subject of inspection holes, where did you put those? So far the only one I can see needing is by the pitot tube.

[Denalifox]

On the subject of inspection holes, where did you put those? So far the only one I can see needing is by the pitot tube.

Alex I didnt put any inspection holes. If I ever need to get into a certain place, I plan to glue a ring and then add a cover. Gotta love Oratex!

[PapuaPilot]

I have two on each wing, one of the outboard ones is for accessing the pitot tube. The inboard ones are between the lift strut attach point and fuel tanks (bay 4?). At times I wish I had more for the sake of internal inspection or the possibility of getting debris or a dead critter, but I can see a lot by pulling the wingtips and two covers.

For Oratex planes this isn't an big issue because you can always add a ring and fabric patch later if you want to cut more holes. With any of the other covering processes you need plan ahead and put the rings and fabric patch on before the finishing coats. During covering you can put as many rings as you want and never cut them open; it only costs the weight of the plastic rings. FYI I didn't even cut out my wing inspection holes for a couple years. I painted the inspection covers (plus a couple spares) and had them waiting for that day.

[jiott]

I recommend putting two in the very back of the tailcone, one on each side of the trim jackscrew mounting. Also one right underneath the rear elevator pushrod swing arm; then you don't have to remove the baggage sack and crawl back there to inspect/lube the rod ends at annual time.

[alexM]

All responses greatly appreciated. Good tip about considering them by the stab trim jack screw. I'm tentatively planning to put my ELT just aft of the jack screw. I've gone through the ergonomic exercise of seeing if I can get it in/out through the openings around the stabilizer. I can, but not by a wide margin. Certainly easier than crawling in the tail cone though.

I'm building a series 5 so I don't have that other pivot point on the elevator push-pull tube.

[airlina]

All responses greatly appreciated. Good tip about considering them by the stab trim jack screw. I'm tentatively planning to put my ELT just aft of the jack screw. I've gone through the ergonomic exercise of seeing if I can get it in/out through the openings around the stabilizer. I can, but not by a wide margin. Certainly easier than crawling in the tail cone though.

I'm building a series 5 so I don't have that other pivot point on the elevator push-pull tube.

Alex, on my Series 5 (IO-240) my ELT is aft of the empennage mounted battery (CG) probably where you are looking to place yours. I am able to remove the ELT for battery install thru the stock empennage panels. As you say its a tight squeeze but doable. Another areas to consider for inspection ports is the aft greaseable plastic bushing for the elevator torque tube . I have 2 ports on the bottom of the fuse here to get one hand in each for this task. Going flying this morning so I'll take a few pics and post later. Bruce N199CL