Protecting the seaplane from birds

We have three kinds of critters that attack our plane. We will take them on one at a time.




Birds like planes. They have lots of places to perch. Planes have many orifices in which build nests. Planes are generally tougher for bird predators to get into. Birds are experts at building nests. They pick a spot and they start bringing in materials. In our neck of the woods, pine straw is the chosen building material.




Hangar doors are pretty good at keeping out most birds, assuming that they are closed and attached to a fairly secure hangar. The next best bet is a set of cowl plugs. I purchased a set from Bruce's Custom Covers http://www.aircraftcovers.com/ for less than $100. These are nicely made to fit your plane and generally have your N-Number embroidered into the cover. They even have little idiot flags that stick up beyond the cowling to signal that you should not start the engine with them installed. I imagine the spinner would catch on the string that holds the plugs together and it would rip them out and toss them aside, before they could let the aircooled engine cook itself, but I know of instances where pilots have taken off with the plugs intalled only to cook the engine. So use these during a post flight and don't forget to remove them during the preflight.




I have still had one bird nest problem even when using the plugs. The bird went in through the hole in the bottom of the cowling where the hot air gets out of the engine and the nose wheel would protrude, if I had one. I am very happy with my plugs and I use them religously. My only issue with them now is they matched the old paint scheme and they have the old N-Number on them. I can live with it. The plugs that came with my plane were just cut out pieces of foam that someone drilled a hole in for the rope that tied them together. The vinyl covered plugs are much nicer and neater to work with. Do a thorough preflight. Look for telltale pieces of pine straw around and on the plane. If you find some, investigate thoroughly.

The other problem planes have with birds is the droppings. These are corrosive to aluminum and at best they can stain your paint. I had bird stain all over the wings of my Cub from where the previous owner let this happen and did not clean the droppings off quickly enough. I have not found a solution for fixing the paint. Statues and blow up representations of predatory birds and snakes in the vicinity of your plane will help scare off some of these intruders. If you have droppings on your paint, deal with them immediately. Damage can start in 24 hours.

Birds

So far this year I have dealt with two bird's nests. The first was while we were still rebuilding the seaplane at Bibb Co. Airport. A bird built a nest in one of my wings while it was still dissassembled and waiting for paint. The latest one was last weekend. The plane was out of the water, on the trailer overnight after some work being done.

Birds built a nest inside the engine compartment. This one was only noticed becase I saw a little bit of pine straw on the spreader bar under the engine. Being curious and a good preflighter, I reached up into the engine compartment where the nose wheel would normally protrude, were it not a seaplane, to find much more pine straw. The bird had built a nest on top of my air intake box. I cleaned all of this out. I caught it early so there were no eggs or birdies harmed in this endeavour.

Last summer, I found a nest only after flying for a bit and noticing high oil temps. This nest was behind the back cylinder on the left side of the plane between the cylinder and the oil cooler (see above pic). Unfortunately these eggs were cooked by the time I found the nest. This nest was not visible except maybe for one strand of pine straw poking up beyond the back cylinder. My plane gives a pretty good view of the top of the engine from the front. Many planes give a very poor view into the engine.

I do use cowl plugs just to be extra vigilant this time of year, and I thought I was pretty safe. The birds are actively nesting and airplane orifices make a pretty inviting spot. They are elevated off the ground, which keeps ground critters away from eggs, have plenty of bird friendly openings, and they provide protection from the elements.

So what are the dangers of bird's nests? There is the obvious fire danger from the pine straw igniting from a hot engine. There is engine damage because air cooled engines don’t get cooled when a birds nest insulates them and blocks the air. Finally there is the corrosion issue from caustic bird droppings on our precious aluminum.

What to do? If you see anything unusual around, on, or under your plane, investigate it further. The time to find a bird's nest is not when you are on fire or doing damage to an expensive engine. If you find something, clean it out thoroughly, so that any blockages are removed and any corrosion is stopped early or never started. Use cowl plugs to reduce the risk. Cowl plugs also require removal before running an engine. There have been many engines ruined by leaving the cowl plugs in and overheating. So go out and enjoy the spring and all the new life that it brings, but do your part to keep that new life out of your engine compartment.