bilge pump

02-17-2012, 02:28 PM

Dean | bilge pump

I have found that any water that should happen to leak into the hull, ends up in the tail because the aircraft sits tail low when on the water. It will not flow forward to the bilge pump in the botton of the step. This probably contributed to the fatality in New Zealand. If you run the nose up on the bank (gear up) it is possible to submerge the tail cone sufficently to allow water to enter the lower hole in the vert stab--especially if you're parked on a beach and the tide comes in. I have installed a second bilge pump in the tail which pumps to the existing pump in the step--one switch runs both pumps.

02-18-2012, 09:29 AM

Russ Kotlarek | Lake Amhib. too

Dean In the Lake amphibs a number of owners did the same thing. Water in the tail even if it did flow forward is also capable of flowing backwards as you plow onto the step. Certainly too much weight in the tail from water is extremely dangerous.

Where in the tail did you put your bilge pump ?

Russ Kotlarek

02-18-2012, 05:58 PM

Fred Lohr

these are very useful comments, as I have also had the experience of parking on a beach thru two tide cycles and having the tail of the plane fill up with water. Most likely, even if I had a second bilge pump, my battery would not have lasted at the rate water probably came in thru the two tubes containing cables to my rudder. This has led me two consider eliminating the "snorkle tube/cable" system of turning the water rudder , back to the original factory system of a push rod (modified with o ring where it passes thru top of hull) on a shaft to the water rudder.

of course the russ method of a stern thruster eliminates those holes altogether

until then, i have decided that i will park my seawind on any beaches with potential for tide with the nose of the aircraft facing seaward if i am going to be ashore more than an hour or two. My current system involves an anchor out front for the bow and a line from the stern to the beach. Tides in my part of maryland are seldon more than about three feet, but it is amazing how fast they come and go sometimes.

it has been my understanding, that once in the water, the water in the tail flows toward the bilge pump, which means you have to taxi in the water until no water is seen exiting the aircraft. Whether this is true fully loaded with a more aft CG, i do not know.

02-19-2012, 03:27 PM


On the thread of bilge pumps: planemarkers helped me swap out all my afte floor inspection covers with clear lexan covers. now, a quick peak verifies if there's water in the bilge. I once made the unfortunate assumption that the bilge was doing its thing, only later to discover a broken zip tie had clogged the bilge pump.

for whatever its worth, i've had my Seawind on a mooring (14' water) for five nights with no problems. My water rudder's (Craig Easter design?) up-cable allows a small amount of water in when I'm in afte CG config, but when the plane is empty, the cable hole is above the waterline (99% certain). I can't definitively say that the bilge pump doesnt kick on several times at night, but it's worked well so far, although I'd like to see if Planemakers can help me move that cable up just a bit further or waterproof the hole. I hate allowing any water, especially saltwater.

Russ, excellent idea with the electric thruster! Please keep up your posts.


02-22-2012, 01:27 PM

Dean | aft bilge pump

Russ, my w/r is electric with sealed compartments on both sides. pump is in center section with weep holes (ala lake amphib) any water leaking from bushings or by compression of tail under water which forces water up over bulkheads in tail section ends up in bilge pump. Dean

08-13-2012, 03:52 PM

Rusty | Lightweight "bilgepump"

You guys are scaring me--makes me want to fill the whole tailcone w/ foam and taped over beer cans. (Beer cans light as foam?--better check that.)

The "bilgepump" on my first boat was a 1/2" thru hull fitting connected to tubing that arced up above the waterline and back down to the bottom on the inside. Planing @ 25mph kept it dry down to the 1/8" gap.

Since "ugly" doesn't bother me much, I plan to mount my water rudder on the outside like any floatplane--do what I can to make it not too offensive to look at.

08-13-2012, 04:54 PM

Tom Saccio | Water in the bilge

Although I get water in my bilge just like all of us do, I think I solved the problem of water coming in through the cable tubes for the water rudder. I took some dense foam, bigger then the tube holes, sliced it half way down the middle and stuck it in both tubes. As the cable moves back and forth it creates a grove where the cable goes through. Any water going into the tube is blocked from entering into the hull through those tubes. It seems to work quite well.

08-14-2012, 03:56 PM


Tom, I think I understand what you're describing... but if its not too late (sealed up that aft-bulkhead) could you post a picture of the foam in the "tubes"? On my water rudder setup, I've got a metal grommet where the stainless rudder cable penetrates. In the picture I've attached - excuse the heavy grease - there doesn't appear to be enough room for foam inside that grommet.

08-14-2012, 08:57 PM

Tom Saccio | Rudder tubes

What you did is similar to what I did. only you used Metal. I took a circular piece of dense rubber cut it slightly larger then the tube, sliced it to slip over the cable and stuffed it in the hole. When the cable moves the rubber does not stop the cable from moving but seals the hole. If water does get in the tube the rubber stops it from going into the fuselage. I put two pieces of rubber in each tube as a precaution. If you need a picture please let me know.

08-15-2012, 06:15 AM


Got it! Thanks.