I have acquired a set of plans for a Druine D5 Turbi. It looks like it would be a nice, economical puttering around airplane. I’ve been thinking about what I could do to bump the gross weight limit up. I’m not an engineer, nor do I play one in the movies, but I figure the place to start is the wing spars. Below are some specs and what I’m looking at doing.
Wing length (from wing root): 4000mm (157.48 inches)
Front spar:
- Upper member of spar: 5 laminations of 60X14 spruce, tapered down to 60X8 at 2100mm (82.7 inches) from wing root
Lower member of spar: 4 laminations of 60X14 spruce, tapered down to 60X9 at 2300mm (90.55 inches) from wing root
Modification: Carry the taper out to 3500mm (137.8) from the wing root. I think the added strength would be worth the relatively small increase in airframe weight.
The rear spar would receive similar treatment.
What do you guys think?
Wing length (from wing root): 4000mm (157.48 inches)
Front spar:
- Upper member of spar: 5 laminations of 60X14 spruce, tapered down to 60X8 at 2100mm (82.7 inches) from wing root
Lower member of spar: 4 laminations of 60X14 spruce, tapered down to 60X9 at 2300mm (90.55 inches) from wing root
Modification: Carry the taper out to 3500mm (137.8) from the wing root. I think the added strength would be worth the relatively small increase in airframe weight.
The rear spar would receive similar treatment.
What do you guys think?