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I'll pile on and say that there appear to be very little, and to channel Battson's post, "not yet clearly defined" or perhaps "not yet provably correct" performance enhancements demonstrated in going from the original wing to the Model B in terms of performance. Some good testimonials and points...

Nev, in my case, it's tinkering with a well-established design because it's fun to try to eek out a little more. From every account I've read, the stock machine performs wonderfully. But, think of the change from Model A to Model B - reportedly a few knots faster speed in cruise (likely owing to...

Mitch: Thanks for the ordinates. I just took them without 3rd party smoothing and just used XFOIL's smoothing routine (the PANE command, if you're deep into XFOIL menus and you want to make it work). So, these results are without Kulfan smoothing, and a comparison of the Riblett 30-613.5...

Mitch: Thanks for the updates. I haven't had a chance to import the new drawings and finalize my comparisons; that could take a bit as it's a busy few weeks here (I'm treasurer for my kids' PTA, and it's tax form season, so that means my spare evening cycles are taken up with PTA stuff). I did...

I got curious so I dusted off my scripts and ran the flaps 30 and 40 cases. I'm attaching a plot of lift vs. angle of attack. These are generated at a Reynolds number that are close to my estimate of the aircraft 1g stall speed at 2500 lb - if I'm generous, I estimate stall speed at 56 mph clean...

Since I've taken time off lurking to reply, I'll add what I've been able to discern. A while back I hand-measured the Mylar drawing and then generated numerically smoothed airfoil forms for analysis. I'm currently using XFOIL, which is a 2D vortex panel code with an integrated boundary layer...

I've been inactive or lurking a bit (remodeling the house instead of building airplane parts after a flood in the kitchen), but found this thread intriguing. I too found that my estimate of the Riblett 13.5% thick airfoil from the description of how they were built from his book vs. the as-built...

Folks: I'm preparing some aluminum to be used for my aileron spar webs (starting small, so the screwups, er, learning, costs less), and am running the numbers to cut the needed material for the blanks. I have found a disagreement with what appears to be standard practice for bending vs. what is...

I’m getting ready to move on from the rib-forming phase to the assembling-stuff phase, and am planning to tackle the ailerons first (smallest spar and fewest parts to redo if I screw up). I’ve been looking over my plans and reading through Eric Newton’s manual (and searched this forum)...

Built the last of my .025 ribs that need the lightening holes flanged today. 86 ribs plus 8 spares (2 of each type L/R) finished. Now I can retire some templates (I hope)! On to stiffeners and some of the smaller ribs...

Trying to make sure I don't miss anything... I can't see the constraining dimension for the false rib on the plans.These are the ones between the rear spar and fuel tank bay. Should I... (1) scale to the drawings, which would indicate an 8-7/16" length? (4-place model B) (2) cut/form long...

It's been a while since I've posted, but I've lurked plenty, and appreciate all the great advice here. I've made good progress on my rib forming (COVID-19 has kept me from traveling for work, which means more shop time!), and I'm about to need to think about what to do next! My plan is to start...

Good day all; been a busy summer and haven't had a chance to post much or work on the Bearhawk. I have been working through ribs at a snail's pace... I'm up to five that I consider airworthy, but another seven that are going in the scrap pile. I was at 3 and 7, so perhaps I'm turning a corner...

I cut my first batch of aluminum a few weeks ago, and in between too much work travel over the past month, finally got around to forming my first ribs. I started with the small ones - the aileron ribs - and let’s just say I need a lot more practice. I don’t think I want these on my airplane...

Anyone used the ATS or other hole flanging tools? https://aircraft-tool.com/shop/detail.aspx?id=FT100 or https://aircraft-tool.com/shop/detail.aspx?id=AE1041 Am getting ready to try my hand at the bob stick method but thought I’d check here to see if anyone had good or bad reviews regarding...

Tried my first round with the router circle jig today - pretty slick! I don’t think I’d use it for much less than 1.5” in diameter... the jig goes down to 1”, but it’s best to hold the center disc in place with screws on either side of the hole centerline, and you need to cut with at...

I’m building up my cutting templates, and am planning to use a router to cut the lightening holes in the templates and in the metal. I’ve ordered a plunge base for my router and the recommended circle cutter jig (thanks!) for the template holes, and will use a laminate bit in my soon-to-be...

Greetings all! I'm building my templates that I will use to cut the rib blanks, and am cutting the templates all at once. I have Eric Newton's Bearhawk Builder's Manual for the wings, and have looked over his site pretty extensively. A few things I'd like to clarify... (1) All of the rib photos...

Step 1 compete: my shop is organized and ready to start pounding out ribs - it’s not much, but it’s enough space to make parts before I have to start kicking cars out of the garage. Not all is in the photo - my bandsaw, mitre saw, and a few other goodies are on rollers next to one of the...

Anyone have a favorite fly cutter? I have this one in my Amazon queue, but see a fair number of one-star reviews. https://www.amazon.com/General-Tools-55-Cutter-Adjustable/dp/B00004T7P1/ref=cm_cr_arp_d_product_top?ie=UTF8 Thanks! Nick