Monday, July 20, 2009

Big toys for little repairs




A couple of weeks ago while training some seaplane students we noticed a squeak while the plane was sitting at the dock. This was odd and we initially decided that the squeak was the dock making noises. We later determined that the noise was coming from the plane since we heard it on the water miles from dock. I went over the plane after each flight, tightening this and that, thinking that I had resolved the issue. Since we had had the floats off during the winter restoration, I believed that some things had just loosened up after the redo.


Finally I found a crack in the forward cross bar that connects the floats to the plane. You could not see the crack unless you looked inside the engine compartment. No more flying would occur until we found a new part and fixed it. The plane would have to be lifted and the engine separately lifted in order to replace this part, since the plane sits on it and the engine connects to the plane through this part. I arranged for my mechanic, Kevin Williams, to come up and look and replace it once I found the part. Buying parts for a rare bird (there are not many Cessna 150 seaplanes) that is 40 years old can sometimes be an adventure. In this case it was fairly easy.


Now I had to find a way to lift the plane. The airplane is built to be lifted by 4 rings located on the tops of the wings. Land planes can generally be jacked up, but this does not work for straight floatplanes which may need to be swapped from land gear to water gear. If we were at an airport with a hangar we could have lifted it with a chain hoist, but here at the lake this is not an option. I investigated a local marina with a huge forklift for boats, but we would not be able to get the plane out of the water safely there. I called the RSC equipment rental people in Alexander City. They hooked me up with a fork lift with an extendable arm capable of lifting 6,000lbs. They were very helpful and delivered the monster as well as demonstrated how to work it.


Everything came together nicely. I had an aircraft mechanic, a huge lifting mechanism, my new part, and good weather. The whole operation took place in a few hours. We only had to remove and replace a few critical and terribly placed bolts. We got big man points and testosterone from operating the large machine and accomplishing our goal. We even got to watch Kevin drive two trucks home. One truck was on the trailer that we used to pull the broken seaplane out of the water, but it was still a sight to see.

I had a excellent flight that afternoon and proclaimed the seaplane to be the best lake toy ever.

Saturday, July 18, 2009

Rejuvenation -- Stripping the plane

The first step in an aircraft paint job is to prepare the surface for paint. This means stripping. Paint adds many pounds to an aircraft and the best paint jobs start with a good prep. I have heard of people painting over the old paint but this is generally a bad idea. Paint sticks best to a primer coat and a primer coat sticks best to a clean metal surface.



There are several chemical methods to strip paint and these are the most commonly used. The other option is sanding, but that is hard work and hard on the airplane. We were looking for a quick and environmentally clean method. We chose to strip the plane using Soda Blasting. http://www.ibssodablasting.com/ This is kind of like sand blasting but using much more delicate baking soda. The process took two days and cost a little over $3,000. I felt that this was expensive, but it was fast, effective, and environmentally safe. The surface of the blasted plane was very nice for paint application. Once the blasting was done we went over the entire airframe and floats to look for damage that needs to be repaired. Can you feel the pain of my wallet?

Time for Rejuvenation-taking the plane out of the water

My plane's paint was getting very tired, the floats were leaking, and parts of the interior could use some love. It has given and given and given over the years. It has sat out in the summer sun...through numerous thunder storms...and alone all winter in the cold. I think it knows that our other airplanes live in hangars.


The 25 year old paint job has done its work, and the floats are starting to leak more than they should. So how does one deal with the rejuvenation of a plane that lives at a dock? You put the plane on a trailer, take the wings off, and drive the plane to a hangar for the work to be done. I had a really good final flight and parked the plane back on the trailer, which is really just a pontoon boat trailer with the bunks set at the proper width for the floats. It was very sad to park it for the last time for months

The first step was to drain all the fuel from the wings, otherwise it would be messy when we removed them. This took about 30 minutes. While that was happening the mechanic, Kevin, started unhooking things like control cables and flaps. Once that was done we stood precariously on the bed of the truck holding the wing tips while Kevin took out the four bolts that connect each wing to the plane. Two hold the strut on and two hold the wing root to the plane. In about 3 hours we had everything dealt with and I watched my dearly loved plane drive away. It would be months before I could fly it again.


Ahead of us we had stripping, fixing everything we can find to fix, replacing the glass, updating some of the avionics, replacing the carpet and the insulation, repairing the floats, and generally doing everything to the plane that can and needs to be done while the paint is not an issue--cosmetic things that have been put off for years because it might mess up the paint. I should get back a plane in excellent shape that looks like new. So she would be down for a while. I would spend more money than I planned. There would be unexpected issues to be dealt with. For now I would just have to fly other types of planes, dream of my rejuvenated plane to come, and pine for for seaplane flying.