Drain holes (A matter of safety)

When I was building "Rough Red" (RV6), if there were an instruction about drain holes I didn't give it much thought. I was aware that I should consider drainage but decided not to put holes at each bulkhead to drain to the outside. Rather I would allow any water to drain through internal bulkhead holes which lead to the tail and let gravity do the work. (This could have been too smart by half!)

Rough red morphed from an RV6 to the 6A so what of drainage now that the tail is off the ground? Well Australia may be drought ridden but lately we have just had a massive amount of rain and I don't have Rough Red in a hangar yet.

While I was checking the control linkages which requires lifting the floor, I found several pints of water round about the rear spar. Quickly fixed with two 1/4" holes at the lowest point, I asked others on the airfield if there were any other aircraft which may have had drainage problems. I was told that there was a Cessna 172 which recently dramatically changed trim on take off due to water ingress.

I guess I am posting this so that if anyone out there hasn't focussed on drain holes then perhaps they should.

Ted
Rough Red (RV6A)

Good Idea and reminder Ted! I putting it in my notes..

I kept meaning to ask that question too. There doesn't seem to be anything in the plans about it.

Does anyone know what the factory line is?

Jim Sharkey

water

There is an old addage from some old pilots. "Don't worry about how the water gets in, worry about how you are going to get it out"! Also, I put a 1/8" hole in front of the spar under the fuel valve just in case fuel leaks into the cabin area. I had a friend who didn't tighten up his lines and he had a leak and we found about a quart of gas laying up against his spar under his carpet. Granted the small hole would not get rid of all that gas but if you have a weap it will show fuel on the belly and you can start looking around. Aden Rich

Spam can

I was working on a 172 that I was a part owner of a few years back. I forget why, but I removed the access panel behind the baggage area to work on the encoder or somthing. I was SHOCKED to see water level with the top of each bulkhead in the tail cone. There must have been several gallons of nasty green water back there. I found drain holes just aft of each bulkhead plugged with nasty green algae. I used a wire to unplug each hole. The scary part is a buddy of mine had flown it the day before like that! Talk about aft CG! Yes drain holes are a VERY good idea!

jsharkey said:

I kept meaning to ask that question too. There doesn't seem to be anything in the plans about it.

Does anyone know what the factory line is?

Jim Sharkey

Click to expand...

Van's encourages building in water drain points in one of the "23 Years of the Rvator" articles. I haven't seen anything in the plans though. I was mildly amused watching all the RV- A pilots at Oshkosh last summer trying to push down on their tails to get all the water out after one of the typical Midwest storms.

I drilled a 1/8" drain hole fwd of every bulkhead. On the 6A the nose sits about 4.5 degrees nose high so it will drain sitting on the ground. I am sure there is no drag increase and no whistling sounds in flight.