By Keith Eisberg, EAA Lifetime 1136501
This piece originally ran in the July 2024 issue of EAA Sport Aviation magazine.
My SkyRocket, a kitbuilt Glasair Sportsman, is my first kitbuilt aircraft. It is also the first kit sold by Glasair and the first kit flying. The famously successful Two Weeks to Taxi program previously offered by Glasair for building an airplane had stopped during COVID which made my build tremendously more difficult than I anticipated. I have been flying for more than 40 years and have rebuilt two Cessnas, but I had never built an airplane from a kit. It was quite an eye-opening experience. Lots of highs and lows but pure satisfaction seeing the final result. Building from a kit is tremendously different than rebuilding a certified airplane. My issue is the fact that I am a perfectionist. So, when it came to building SkyRocket, I did not compromise and in fact continued to build it along the same principles of a certified airplane. I started the build in April 2022 with a builder assist from a one-man shop that told me the airplane would be finished in two months, and then I’d be able to fly it. That was wrong in so many ways. After those two months, I was on my own to complete the airplane. There were other experienced Glasair builders that helped me when I needed extra help. It took me until September to be ready for the first test flight. And it took me another year to get the airplane completely finished to my standards — one and a half years total.
My mission statement: Build a four-place aircraft burning fuel at 8-9 gph yet be able to fly fast across the country from the Midwest to the Idaho backcountry for slow, controlled landings. And, the fuel system must be a simple gravity-fed system rather than extra fuel pumps and tanks in the outer wings. I fly tailwheel, which means I want the weight of the fuel inboard.
To meet my mission, I made several modifications to the factory kit design. Modifications included a wet wing, extended gear legs, welding a metal support bar inside the safety cage to attach a four-point shoulder harness, designing carbon fiber floorboards in passenger and cargo areas, adding an extended baggage area, Beringer wheels and brakes, Michelin 7.00-6 tubeless 8-ply tires, and a few other modifications. The most dramatic issue was building a wet wing that eliminated four metal fuel tanks and two fuel pumps. With the assistance of Ted Setzer, we designed a wet wing that allows for a Sportsman STOL kit to be added to the leading edge if ever in the future I wanted one. The fuel capacity went from factory 50 gallons to 64 gallons in my wet wing. We had to make a separate compartment for the flap bellcrank as seen in the picture. Note the detail for sealant that was placed in the critical areas. Each rivet has sealant on, in, and around it, which was critical to prevent any leaks. It became more difficult once we added the second skin, leaving only access holes to complete the seal around each rivet. We tested the tanks by pouring fuel into them and letting gravity do the work.
I chose a Lycoming IO-390 Thunderbolt engine, adding port and polish at the factory. The port and polish provide an additional 10-15 hp for a total of 225 hp. Mounting the Lycoming engine went fairly smoothly. Using a standard engine hoist, we mounted the engine and bolted it down. I chose the Hartzell three-bladed carbon prop, an 80-inch Pathfinder. The prop went on quite easily, but it took me a while to get the safety wires correctly on the prop bolts. I chose double P-Mags for my Thunderbolt. I simply love P-Mags along with the engine and prop.
Since I fly backcountry, I added an additional bar to the steel safety cage upon which I mounted a four-point shoulder harness release system. I’m a parachute rigger so I designed the shoulder harnesses and had a master parachute rigger build them to my specifications. I custom designed carbon fiber floorboards that extend continuously back behind bulkhead B. The floorboards were built with piano hinges, allowing for storage underneath. A canvas bulkhead cover provides quick access to the extended baggage area. I built in nut plates for attaching the floorboards with bolts rather screws. The nut plates with bolts make it easy for annual condition inspections. This design allows easy conversion from carrying passengers to converting the area into a true utility aircraft capable of carrying camping equipment, bikes, hunting supplies, etc.
For the past year I have continued to tweak and perfect the airplane for even better handling for my mission. I am redesigning the curved control stick that came with the new interior design but had issues in its design. Soon I’ll test-fly the big 26-inch Alaskan bush tires mounted on separate Beringer wheels. Beringer wheels allow you to easily and quickly change the wheels without changing the brake system.
Continuing to work on my airplane with an FAA repairman’s certificate has given me great satisfaction that my SkyRocket is truly my modified design, and it’s nearly perfect.