Hefty
New Member
Hi folks, I'm new to HBA and was looking for intelligent input to raise gross weight of a design from 630lbs. to approx. 700. Empty weight is listed as 405lbs. The useful load available is not quite enough. The drawings I have are from 1979, and there have been any number of innovations since then. The plane originally used a Revmaster VW engine that had to have weighed at least 150lbs. Using a Rotax 503 will save about 50lbs. and still provide comparable power. I'm obsessed with the wing design. Two wooden spars on each side are made of spruce. Wood is not to be maligned. But aluminum spars(tube) or at least cladding of the wooden spars would seem to offer greater strength. Can't help but wonder if the weight difference would justify that approach. Mr. Kolb seems to have been influenced by the design, maybe not. A high wing pusher wasn't new 30 years ago, but Kolb offered a design in the early 80s that looked much like the design I'm speaking of, Hovey's Beta Bird.
Seems that scaling the wing upward a little would offer an increase in gross, and the airfoil would not be changed. I really don't want to try my hand at engineering. I lack the background needed. I prefer this design, but it is lacking for my needs. If I can increase the gross by ~11%, I'm there! If 11% is asking too much, then I guess it's not to be. I choose to be optimistic. I'm thinking about Molt Taylor's Paper Glass to make ribs, but wonder if that method will be any stronger or lighter than Mr. Hovey's use of aluminum and spruce.
Any constructive ideas are welcome. Thank you.
Seems that scaling the wing upward a little would offer an increase in gross, and the airfoil would not be changed. I really don't want to try my hand at engineering. I lack the background needed. I prefer this design, but it is lacking for my needs. If I can increase the gross by ~11%, I'm there! If 11% is asking too much, then I guess it's not to be. I choose to be optimistic. I'm thinking about Molt Taylor's Paper Glass to make ribs, but wonder if that method will be any stronger or lighter than Mr. Hovey's use of aluminum and spruce.
Any constructive ideas are welcome. Thank you.
