What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Fuse Drain Hole

L

lr172

Well Known Member
Did a search but couldn't find anything. Where are you guys putting a fuselage drain hole in the 10? I have 2 on the 6A and glad I did, as I have had a few events where I took on a lot of water.

Just wondering if anyone has taken effort to find the best spot. I am not on the gear yet, so can't really tell where the low point will be.

Larry
 
My basic plan was going to be: build the fuselage, ground level it, throw a cup of water in at various locations and see where it ends up, then determine if a drain hole is appropriate there. I'd be interested in hearing whether others have done this already.
 
1001001 said:
My basic plan was going to be: build the fuselage, ground level it, throw a cup of water in at various locations and see where it ends up, then determine if a drain hole is appropriate there. I'd be interested in hearing whether others have done this already.
Click to expand...

Ah, maybe some kind of oil, linseed or something instead of water.
 
BMC_Dave said:
Ah, maybe some kind of oil, linseed or something instead of water.
Click to expand...
Why not water?

A couple of cups of clean water isn't going to harm your fuselage; however, oil of any type will be mess to clean up and will attract dirt and grime.
 
N941WR said:
Why not water?

A couple of cups of clean water isn't going to harm your fuselage; however, oil of any type will be mess to clean up and will attract dirt and grime.
Click to expand...

But won't foster the transfer of ions.

I mean it's not terrible, and it's not like water isn't going to get in there at some point. But why intentionally introduce it? And wicking between surfaces as Bob mentioned, seems... unnecessary.
 
Last edited:
Even

Even at that low RH, if the water gets in a sufficiently tight space, it will take a long time to evaporate...but now we are splitting hairs...

If someone does do the test, please lost the results!
 
rocketman1988 said:
Even at that low RH, if the water gets in a sufficiently tight space, it will take a long time to evaporate...but now we are splitting hairs...

If someone does do the test, please lost the results!
Click to expand...

That's OK, it will usually have 2 months to do it...:D
 
BMC_Dave said:
But won't foster the transfer of ions.

I mean it's not terrible, and it's not like water isn't going to get in there at some point. But why intentionally introduce it? And wicking between surfaces as Bob mentioned, seems... unnecessary.
Click to expand...

Don't worry; I'm sealing the entire inside of the fuselage with Rhino Liner anyway.
 
lr172 said:
Did a search but couldn't find anything. Where are you guys putting a fuselage drain hole in the 10? I have 2 on the 6A and glad I did, as I have had a few events where I took on a lot of water.

Just wondering if anyone has taken effort to find the best spot. I am not on the gear yet, so can't really tell where the low point will be.

Larry
Click to expand...

Mine is on gear, engine mounted, and in the garage.

Based on eyeballing it, I would say that behind the rear spar and in front of the main spar are the two obvious locations. The rear spar *looks* like the low spot, but any water that gets in the front of the airplane would be blocked by the main spar, which I certainly don't want to get wet and stay wet. Therefore a hole in front of it...
 
Don't use any oil-like substance. It'll attract dirt and you'll have a long-term problem.

Back after I'd had my Cessna 180 taildragger a few years, I decided to clean out the fuselage. I removed the interior, pushed the plane onto some grass, and proceeded to spend a warm weekend with swimming trunks, a hose, a bucket and some rags and a lot of soap. I'd let water flow into the tailcone, get it soapy, and scrub it out. Then let it drain and rinse it.

I found that water would accumulate anywhere there was a relative low spot. I had to clean out most of the drain holes - they were at every bulkhead, about 1/4" diameter. They'd gotten clogged by dirt over the years. Once open, they did a good job of letting the fuselage drain.

Now this was in a taildragger. I'd expect that a nose-wheel airplane will accumulate water more under the cockpit floor than in the tailcone, but don't neglect that. You should assume that someone will aggressively try to clean it out, and if you don't have proper drain holes they'll drill some. Best to do it for them.

And I do recommend using a LOT more than a few cupfuls of water. You'll be surprised where it migrates to.

Cessna had installed some neat little snap-in drain fairing plugs. They didn't restrict the hole much but provided a rearward-facing exit. Unfortunately I don't have that part number now.

Dave

Dave
 
Kyle Boatright said:
Mine is on gear, engine mounted, and in the garage.

Based on eyeballing it, I would say that behind the rear spar and in front of the main spar are the two obvious locations. The rear spar *looks* like the low spot, but any water that gets in the front of the airplane would be blocked by the main spar, which I certainly don't want to get wet and stay wet. Therefore a hole in front of it...
Click to expand...

Thanks. Be carefull with too many holes. The bottom of the interior of my 6 is very oily. I am convinced that either the water coming in the hole brings the oil from the belly or, more likely the stream of air mixed with atomized oil from the breather works into the hole (negative pressure in cabin). There is really no other way the interior fuse bottom could have gotten an oily residue.

Larry
 
David Paule said:
Don't use any oil-like substance. It'll attract dirt and you'll have a long-term problem.
Click to expand...

Not sure where this is coming from. Linseed oil is used in tubular structures, though somewhat more protected from dirt. Hinges are lubed with grease and those are flapping out in the elements. And have you seen how greasy an engine cowl is? Had a Piper wing apart and it was pretty dirty in there after 39 years, primed aluminum was fine...

But sure, pour loads of water in your fuselage, couldn't hurt and totally necessary right?
 
Definitely put one in the bottom of the rudder fairing
We found a good bit of water in there during the prebuy on the -10 (plane had been washed)
 
Hey Dave,

If the fuselage wasn't going to get water in it, there'd be no need for drain holes, right? And it *is* going to happen, unless you only fly in the Sahara or some place similar. In the southeast corner of the USA, there are mornings after a cool night when there are big puddles of water in/on/under anything metal, including airplanes. My -4 can condense way more than a cup of water when conditions are right. And that's in a closed hangar.

Charlie
 
rv7charlie said:
Hey Dave,

If the fuselage wasn't going to get water in it, there'd be no need for drain holes, right? And it *is* going to happen, unless you only fly in the Sahara or some place similar. In the southeast corner of the USA, there are mornings after a cool night when there are big puddles of water in/on/under anything metal, including airplanes. My -4 can condense way more than a cup of water when conditions are right. And that's in a closed hangar.

Charlie
Click to expand...

Not contesting that water gets in there, heck I even say so in one of my posts if you go back and read it... But why on Earth would you do that on purpose?

Sometimes I find it useful to describe, in literal terms, what action is being advocated.

This is what some of you are advocating he do:

Intentionally introduce water into your fuselage so every nook, cranny, and faying surface of the lower portion of an aluminum aircraft structure will be immersed.

This seriously sounds like a good idea? Doing this is worth it, you can't just eyeball where you think moisture could accumulate without introducing a corrosion-inducing solvent to critical joints in your primary structure? Technical counselors don't see anything wrong with this and say water that has wicked into such areas will "just dry out" (paraphrase)?

This is bananas...
 
Please re-read my earlier post. It happens *every time* the plane is in a humid environment and the temps swing through the dew point. Our emotional reactions to this doesn't alter reality for the plane. :)
 
rv7charlie said:
Please re-read my earlier post. It happens *every time* the plane is in a humid environment and the temps swing through the dew point. Our emotional reactions to this doesn't alter reality for the plane. :)
Click to expand...

Re-re-read the post where I acknowledge this happens before you even commented...

Again, why on Earth would you do this on purpose?

Is your only rebuttal seriously "Well moisture accumulates there already, so it doesn't matter if we completely submerge the airframe"? Does that make logical sense to you? ;-)
 
No (though there would be minimal impact even if you did, in controlled conditions). Just that a controlled application in controlled conditions (as others have advocated) will have far less negative impact than undetected retention of water in the belly or tail. That's the point of checking & drilling the holes; so any water that accumulates will drain out instead of remaining inside.

Charlie
 
Or you could, you know, use something that won't foster the transfer of ions, like linseed oil or CorrosionX. Products that are literally designed for this...

Yet another process advocated here that people who build commercial airplanes for a living have laughed at, take of that what you will. Do not intentionally fill your fuselage with water. If you do, make sure to add lots of salt first :rolleyes:
 
You must log in or register to reply here.
Back
Top