I acquired a 35 HP Global 1/2 VW engine, and decided to build a HummelBird behind it. This is my first build, so I've done some research before deciding on it, including looking up every NTSB report on the plane and reading the entire builder's group archive (1999-present) on Yahoo. I started copying from the builder's group to a file the answers to where people had difficulty, but only from 2008-present, I'm going back through them to get the rest so I can know what to expect. A few established, Hummel- acknowledged modifications to the plans will be made:
Riblett GA30-613.5 Airfoil replacing the Clark Y. This will require a slightly larger spar web, and a small angle to the front spar.
Firewall 2 inches forward. This will allow for a slightly larger fuel tank.
Engine mount 2 inches longer
Other possible modifications that I will decide upon later, these have been done before by others:
Wing tanks
Rudder cables instead of pushrods.
Plans were received 9/5/17, since then the garage has been mostly cleaned out and organized thanks to a convenient junk day in my neighborhood, and some needed tools purchased/ordered. The Riblett airfoil and flange have been modeled in CAD, still a work in progress. I plan on having the ribs laser cut, as I can use a laser very inexpensively. I'm going to start work on the fuselage, so I have some time to complete this.
The first physical work on the actual project began 9/28/27, a "light table" (actually a sheet of acrylic on two milk crates with a clamp lamp underneath) is being used to trace the bulkheads and all other full size parts to plain white, removable, contact paper, a suggestion from the builder's group. This will allow me to cut the parts out and keep them protected until used, and preserves the plans. All full size fuselage parts on the plans but one bulkhead ("C") have been traced, still need to trace the bulkhead forms. Forms will be made this weekend/next week, then it's aluminum cutting and smashing time.
Riblett GA30-613.5 Airfoil replacing the Clark Y. This will require a slightly larger spar web, and a small angle to the front spar.
Firewall 2 inches forward. This will allow for a slightly larger fuel tank.
Engine mount 2 inches longer
Other possible modifications that I will decide upon later, these have been done before by others:
Wing tanks
Rudder cables instead of pushrods.
Plans were received 9/5/17, since then the garage has been mostly cleaned out and organized thanks to a convenient junk day in my neighborhood, and some needed tools purchased/ordered. The Riblett airfoil and flange have been modeled in CAD, still a work in progress. I plan on having the ribs laser cut, as I can use a laser very inexpensively. I'm going to start work on the fuselage, so I have some time to complete this.
The first physical work on the actual project began 9/28/27, a "light table" (actually a sheet of acrylic on two milk crates with a clamp lamp underneath) is being used to trace the bulkheads and all other full size parts to plain white, removable, contact paper, a suggestion from the builder's group. This will allow me to cut the parts out and keep them protected until used, and preserves the plans. All full size fuselage parts on the plans but one bulkhead ("C") have been traced, still need to trace the bulkhead forms. Forms will be made this weekend/next week, then it's aluminum cutting and smashing time.
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