Bowlus anyone?

[Knoll53]

Nice work Petr. I'm convinced. Chuck is the real deal. That provides quite a few leads.

Thanks,
Kent

[stihac]

Nice work Petr. I'm convinced. Chuck is the real deal. That provides quite a few leads.

Thanks,
Kent

You're welcome.

Petr

[dgliderguy]

So, Kent, why do you say the Col. Thacker Baby Bowlus is the worst flying airplane in your fleet? Won't settle down in pitch? Bad adverse yaw in turns? Won't climb in light lift? Flutter problems? Surprise tip stall?

I'm curious to know because I have this plan in my stack, and I'm planning on doing this one from scratch some day. (Even have the aluminum tube set aside for it, and I've found and corrected all of the plan inaccuracies.)

This is the first I've heard that it doesn't fly well. Please elaborate.

[Knoll53]

So, Kent, why do you say the Col. Thacker Baby Bowlus is the worst flying airplane in your fleet?

Sure Don, let me elaborate. Of course this about the airfoil. I built the SkyBench kit. It does not match the Thacker plans in many respects. Maybe SkyBench changed the airfoil too. My comments are about the kit, not the Thacker plans.

Compared to my other gliders, this has a poor glide ratio, a poor sink rate and stalls at a higher speed than I would guess based on it's wing loading and wing area. That is to say, there is a lot of wing area and it has a big chord. If I were to build this glider again, I'd change the airfoil.

It's worth noting that I fly slope at the coastal cliffs here in California. The landing zone is a challenge for a big scale ship and you can bet that it is rare to see a scale ship out here. If I flew aero tows exclusively on a big mowed lawn, I might not be such a critic, but I doubt it.

David Alchin also built this kit and he too has nothing good to say about it. I believe that he has flown his only once or twice.

Other than that, I flies fine. Or at least as fine as you'd expect an open cockpit vintage glider with wing struts to fly. That is, it's a draggy glider so it needs an airfoil that performs well as lower speeds. I'm sure that you have your favorites.

If you are designing you build from scratch, don't forget to design your wing struts for compression loads that occur during a hard landing. Also, I'd improve the spar design. Snapping the outer wing panel off on a hard landing is easy due the stress concentration created by the plywood panel joint.

Good luck with your project and I hope we see a build log from you on this one.

Kent

[Beazld]

I'm curious to know because I have this plan in my stack, and I'm planning on doing this one from scratch some day. (Even have the aluminum tube set aside for it, and I've found and corrected all of the plan inaccuracies.)

I have this in the to-do pile. Can you tell me more about the inaccuracies?