by Doug Nelson
“The Bird Boat”
I was looking through a boat trader magazine one Sunday afternoon when I came across a Tunnel Hull I/O and immediately thought of the boat we all worked on while I was in the service. I sat down and using the pictures in the magazine, drew up a set of sketches on how to go about building one. From the sketches, I refined the plans with some help from ideas and mistakes from past experience.
I then put together a parts list of materials I would need to get it started. The skeleton would be 2×6 Birch, the skin would be 2 layers of ¼” marine plywood and the exterior would be fiberglass. I went to the local home improvement store and purchased what I needed. I began with the runners and built the frame from there up. I then sheeted the tunnel to give the frame rigidity. Next, I sheeted the sides, then the top. On the deck, I laid mahogany tongue and groove boards side by side, sanded them smooth and routed the edges.
I went to the local junk yard and bought a 1959 Cadillac engine and transmission. I built the engine mount at work and secured it inside the hull. I then set the motor on the mount and ran a shaft through the hull. The tunnel was one foot deep, so I needed to extend the shaft to reach the water. This meant I needed some type of brace to support the propeller end of the shaft which was one foot behind the transom.
I then began the dizzying task of fiber glassing the hull. I put 2 layers of glass cloth and 5 coats of resin. The last coat had color added. I was now ready to take it to the river and see if it would float and if the engine would push it. I called up Bill, Terry and Allen, and we loaded it on a flat trailer I had rented from the junk yard. I designed it to look like my Superbird with the big dorsal fin and pointed nose. We hitched the boat to the Bird and off we went to the river.
When we pulled up to the boat ramp, it made quite a commotion. We shoved it into the water, and it floated. Not only did it float, I had done the math correct and it floated just at the water line. The four of us got in, and I started the engine. I put it in reverse and we began to slowly leave the dock. All of the other boats had either come to a stop or were going very slowly to see what we were going to do next. I had left the automatic transmission on the engine so I shifted to neutral and revved the engine. I put it in low, and we began to move forward. As I increased the throttle, our speed increased. I didn’t have a speedometer but when the engine was about ¾ max I shifted into second. I forgot to throttle back, and we took off like we were shot out of a cannon. I immediately throttled back and put it in third. I eased the throttle forward, and the boat rose up on the one foot wide skis. I would guess we were running about 40 mph at half throttle when we hit the wake of another boat. We heard something crack and then pop. I slowed down to a crawl so we could try to find out what had happened.
The torque from the engine had pulled a mounting bolt through the hull and we were leaking badly. We headed for the dock but by the time we got there, the boat was sitting six inches lower in the water than it had been. I backed the Bird up to the dock and we pulled the boat on to the trailer. The bilge pump was pumping as fast as it could but it wasn’t keeping up with the leak. We tried to pull the boat out but with all the added water it was much too heavy. A guy with a 4-wheel drive jeep, seeing our problem, came to assist us. I pulled the Bird away and he hooked onto the boat with his jeep. His tires just spun, so I hooked on to him with the Bird and we finally got it out. I would need to reinforce the hull where the mount was located before we would try it again.