Bearhawk STOL mods

Well, when someone can get to it, we can look and see what it will take to redesign the hinge. It's just an alternate mount that can be fabricated and we loose a few degrees of deck angle on landing, that would be for sure worth it.

I have access to a bunch of actual aeronautical engineers that I do contract IT work for, so I actually have what I need to go down this road, except for my wings on the table as they are still crated. Pehaps in a few weeks.
 
Unless I'm mistaken, you guys are talking about doing the same thing I mentioned that Shane Madson had done with his cub, with designing a lower hinge point, allowing the flap to roll back as it deploys. Both the Maule and the Husky use this dropped hinge point.
 
Yeah, the husky’s are scalp slicing headache making implements of blood sourcing. 😬

Bear in mind that the greater the hinge offset, the greater the throw is required for the control arm. So to get the same angle of flap deployment you’ll need to adjust the bell crank size. This will also affect the pull required on the flap arm. It’s a typical snowball that just requires forethought. Easily achieved.
 
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500AGL said:
Yeah, the husky’s are scalp slicing headache making implements of blood sourcing. 😬

Bear in mind that the greater the hinge offset, the greater the throw is required for the control arm. So to get the same angle of flap deployment you’ll need to adjust the bell crank size. This will also affect the pull required on the flap arm. It’s a typical snowball that just requires forethought. Easily achieved.
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The Husky hinges are dropped significantly, like a really long way. That dropped hinge would interfere with the rear passenger door on a BH. The Maule hinge appears to be dropped about an inch. I think maybe I could make that hinge clear my door, and hopefully I won’t scalp myself on it.

Also worth noting, the max deflection of Husky flaps is 30deg. Sometimes, depending on the flaps design, a large deflection angle is not necessary.
 
You might be able to also offset the actuating arm attach point on the flaps, and keep the stock bell crank.
 
I agree Whee. There is a point where the flap lift is offset by the drag of the barn doors. Sometimes you want just one half of that equation. Other times you take both and want more.
My goal would be to have 2-3 notches of progressively better lift, before dropping into the 4th notch and getting the whole anchor.
Maybe the notches should not be spacely evenly. Set the plane up and fly it with progressively deeper settings until you find the sweet spot, and use that as the last notch before the full air brake.
pb
 
Threads like this can make me start thinking different is always better. My interests lead towards frugal performance gains, so I'll keep mine as Bob designed it. So I ask this next question out of curiosity.

What is the drawback of the Cessna Flap design which is able to the Fowler action without an exposed hinge by using flap tracks?
 
Bcone1381 said:
Threads like this can make me start thinking different is always better. My interests lead towards frugal performance gains, so I'll keep mine as Bob designed it. So I ask this next question out of curiosity.

What is the drawback of the Cessna Flap design which is able to the Fowler action without an exposed hinge by using flap tracks?
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I would say the only drawbacks are weight, cost, and the rollers have a tenancy to eventually fail.

While there is no perfect airplane, and I'm glad to not have to deal with fuel bladders, spring gear, and cessna parts, the flaps are something they absolutely got right, as well as the trimmable stab on the 180.
 
I still think really big fowler flaps and a THS (trim-able horizontal state) might go together. The change in center of pressure is so great with the flaps, you need the THS to handle the trim change. A big THS can be much more powerful than the elevator, which makes its' function (electric or manual) required.

I always read this thread, but cost/benefit has me sticking with stock flaps. I like the stock performance compromise, but always willing to learn.
 
Post 1962 Cessna 182s don’t have a THS, they have a trim tab on the elevator. They do have the same semi-flower flaps as the earlier 180/182. So, the Cessna semi-Fowler’s and THS don’t have to exist only with each other.

I think several have said this before, I know so have; For the vast majority of pilots/builders a stock BH will do everything you need or want without issue or complaint. The few of us that want to fine tune our aircraft to exactly fit our niche have the opportunity to do so and that’s why we entered the EAB world and built our airplanes. Otherwise we could have bought a Maule, or Cessna, or... and made it work like we could make a stock Bearhawk work.

I’d love to have Cessna style flaps on my airplane but the wings have to be designed for them and I don’t know that they are. It would probably be easier to just put Cessna wings on a BH fuselage than it would to re-engineer the wing and flap mechanism to a Fowler.
 
I spoke with the guy who did the double slotted flaps for that BH. He would be happy to figure out and make whatever mount mods you need and stick it all together for you. It all just added up to more than my budget - by a lot!
 
My thinking on the upgraded flaps has really come full circle in the last year. On a a/c with plain flaps the difference between clean and full flaps stall speed might be 10% or so. On a plane with big fowler TE flaps, as well as full span LE slats (I think the two go together as well), that difference is more on the order of 30-40%. Putting the flaps ups and down is a procedure that takes 1-5 minutes. On a go around, when light, exceeding flap limits is pretty easy to do. I used to assume that flap limit speeds were for structural reasons, but the more i think about it, they might be for controllability as well.

The more powerful the flaps, the more care you need to take putting them up and down. Putting those more powerful flaps on a manual handle, with a single pilot, might add more risk than the potential reward is worth, or at least increase the workload at exactly the time and place I don't want or need it (tight confines, lots of terrain).
 
Asymmetric deployment is a different issue, but also relevant. But not the topic I am talking about. It is also not something that came to me immediately. It is something that I thought about over a year or two. I tried to think about it in a way to describe it. Someone with experience flying with very powerful, high lift devices will be able to understand it easily. Someone without that experience might think I am smoking crack.

I have tried to think of analogy to explain it. Maybe the best is the Piper Aerostar and Mitsubishi Mu-2. Both were, by far, best of class airframes. Both had, by far, the worst safety records for a long time. There was nothing wrong with either airframe. The pilot training in the US was not adequate to cover the performance, and handling characteristics of either.

The more powerful the high lift devices, the greater the transition from cruise to approach, or vise verse. Going from flaps 40 to zero with simple flaps is a lot different than doing the same with fowler flaps and slats. The workload is probably 10- 20 times greater, and longer. I don't think I want to manage that while trying to fly my way out of a canyon.
 
Again, I don't know a great way to describe it. If you modify the aircrafts flaps so that the stall speed goes down another 10%, it doesn't just affect that speed. It also affects the lift/drag at all other speeds while the flaps are deployed.

You might be shocked at the amount of time a 2 pilot crew spends managing speed/flaps on an airplane with flaps that change the stall speed by 30- 40 %. On a bush plane that has flaps that change the stall speed by 20%, it might be more workload than I want to manage as a single pilot that only flies 5-15 hours a month.

I wish I had a better way to describe it.
 
I think I have an awful lot of experience with high lift devices, leading edge slats, very large fowlers(that have more surface area than an entire 73 wing). I have no idea what you're talking about controllability wise. The workload a flap speed induces is no different than any other type of flap. Especially if you've ever seen how they are implemented on small airplanes. It's very different. There's literally no input from the pilot on the current slat designs, and the fowlers are only good for about 4kts typically. Which while over 10% of stall speed, isn't much. I think you're WAAAAAY over thinking this.
If I blindfolded you and put you in the airplane and we went flying in a cub with the pstol flaps, you'd never know what type of flaps were on it from a function in the cockpit point of view. The retract and deploy exactly the same. A lot of people do them 100% at once. As in no flaps or ALL the flaps.
 
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Semi fowler flaps with a *long* track, like the Cessna, put a lot of torque on the rear spar. The risk is cracks developing in the wing skin.
 
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You can easily control a Bearhawk with fully asymmetric deployment, I have flown with one flap down and one up for 45 minutes (long story, already posted here). Passengers didn't even notice...
 
Would a sportsman style LE cuff make any difference on the Ribblet airfoil? Does anyone know if this has been tried on a Bearhawk?
 
Hewko said:
Would a sportsman style LE cuff make any difference on the Ribblet airfoil? Does anyone know if this has been tried on a Bearhawk?
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When I put on my science hat, my answer is I don't know, and I don't know of anyone who has tried it. When I put on my intuition hat, I have to wonder of it's like putting ketchup on a high dollar steak. As with any proposed mod, the key question is what is the shortcoming that the cuff would be addressing?
 
Hewko said:
Would a sportsman style LE cuff make any difference on the Ribblet airfoil? Does anyone know if this has been tried on a Bearhawk?
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Having read Harry Ribblet's book I would say no. The sportsmans cuff is a bandaid on a poor airfoil. Harry Ribblets airfoils corrected the design deficiencies of the NACA series like the 24012 used on a lot of Cessnas. The sportsmans cuff is adding leading edge droop to the 24012 airfoil. This is already designed into the Ribblet 30 series airfoils. Adding additional droop on a Ribblet airfoil would have unpredictable results, might improve one end of the speed envelope with major detriment on the other end. So how about the 4412 airfoil on the A model? Bob modified the 4412 adding leading edge droop. There are two methods of calculating this change. According to Harry, Bob did it the correct way.
 
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In essence I agree with Rod.

Both the A and B wings were designed with slow flight in mind, the Cessna was not designed for that specifically. While I think the Cessna wing is pretty good on it’s own the Sportsman cuff offers better slow flight for the guys that want it.
 
It would certainly make a difference (not necessarily better) - but it depends, what are you trying to achieve? If you only care about slow flight, adding camber and increasing angle of incidence are no-brainers. If you also care about cruise speed, maybe not such good ideas...
 
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So would it be possible during the build to make the standard Bearhawk flap into a fowler flap by attaching a second lower flap pivot point, about 2 inches lower similar to a Maule? And then moving the flap actuating rod attach point correspondingly lower on the flap? The roughly hand drawn in extension point on the attached image shows it better than I can explain it. Is this worth trying or will it introduce problems?
 

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Yes that is the Maule flap idea discussed on previous pages, but no that is not a fowler flap - that is a slotted flap.
 
Has anyone tried flap seals? I know the gap is small but air is smaller. Gap seal on my elevator and rudder worked quite well. Tape along the bottom like my elevator and rudder would be easy to do.
 
Helidesigner said:
Has anyone tried flap seals? I know the gap is small but air is smaller. Gap seal on my elevator and rudder worked quite well. Tape along the bottom like my elevator and rudder would be easy to do.
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It for sure couldn't hurt, but I'm not flying yet, so I don't know.

I wonder how much difference lowering the flap hinge point below the wing will help, like a Husky or Maule. I suspect a bit, but then we would have to figure out if the wing is strong enough to handle the change in forces.

I also wonder how well your drooping ailerons work. Would you do it again? Any details you can share?

schu
 
Helidesigner said:
Has anyone tried flap seals? I know the gap is small but air is smaller. Gap seal on my elevator and rudder worked quite well. Tape along the bottom like my elevator and rudder would be easy to do.
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With the plain flap on the bearhawk you're not really counting on any air up and over to re-energize the boundary layer. I don't think it'd do anything.
 
I'll expand on curiosity of flap effectiveness.....

What about Cessna Style flap tracks. You get a true "fowler" flap action and miss out on bumping your head on the hinge that hangs down.

Screen Shot 2021-10-12 at 7.33.34 AM.png
 
schu said:
I wonder how much difference lowering the flap hinge point below the wing will help, like a Husky or Maule. I suspect a bit, but then we would have to figure out if the wing is strong enough to handle the change in forces.
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The wing has been modelled by the guys at Javron, it was found to be strong enough to hang double slotted AA flaps on it. I am sure a lower hinge point would not be a lot different. Maybe cause to be more careful with flap speeds.

This is my personal favourite to improve Bearhawk performance, in terms of bang for buck.
 
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I have looked at this in detail. Its fraught with issues and you end up having to do major modifications. The flaps also have to get a lot smaller (shorter cord). The double slotted flaps are a much simpler bolt on solution, less work and cost overall.
 
Completely agree, so much so that I've delayed forming my flap nose ribs while I explore a few options (I otherwise finished all the ribs and was moving on to spars prior to entering remodeling hell). Torsional strength of the wing box was one of my concerns; I don't do structural analysis for my day job and haven't done shear flow calculations since college (now over 20 years ago). A better lifting flap is going to increase the lift on the aft part of the wing as well as the associated pitching moment, so it'll increase rear spar bending loads and overall skin/wing box shear loads. It's good to know that the analysis has already been done for a different flap system that is probably more effective (I'd think a double-slotted flap would have higher loads than even a well-designed single-slotted drooped hinge design). Don't worry, if I do something crazy like actually try to build it, I'll talk to Bob first.

A redesigned tail may get rotten tomatoes thrown my way, but that *may* also be a good "bang for the buck" improvement, particularly if the high-lift capabilities of airfoil/flap system are improved. The Bearhawk tail is beautiful, and the ribs introduced with the Model B makes it even more functional. But, I've seen a lot of discussions on this forum about handling qualities at various CGs - fore vs. aft, and the ability to use the useful load. Even with the profiled tail, I think the thickness/chord ratio is somewhere around 6% for horizontal stab, if I've done it right. My hypothesis is that doubling that (something like the NACA 0012 profile) could yield a little more performance, or conversely require slightly less elevator deflection for trim. It could be more of a problem, particularly at forward CG, if one were to design a flap with higher lift (which would inevitably increase nose-down pitching loads). I'll throw in my usual caution that I have no reasonable analysis result or Bearhawk flight experience to back this up; just what I've tried to read between the lines in the forums and other reports online.

Nick
 
This is a very interesting discussion.

I'm curious - what issue would be solved by changing the flap design ? Where is the Bearhawk falling short ? Does it need to land slower ? Shorter ? Fly the same approach speeds with more control ? Better "over the nose" visibility ? I've yet to fly a B model and mine will probably be the first that I get to fly, but I'm interested to see if the pitch sensitivity (and pitch trim sensitivity) from the servo tab is still present in the B model.

My point being is that I wonder if there are lower hanging fruit on what is already well proven aircraft before getting into more complex areas such as the flap design. Examples that come to mind are reducing the pitch sensitivity, and increasing pitch control at forward CG/low speeds, ensuring that adverse yaw is limited through correct rigging during test flying, lowering flap bar forces etc.

On the other hand, if it's a case of doing it because it's an experimental aircraft and we need a project, then bring it on !
 
In my option the most significant item to improve is visibility over the nose when doing true short field work. The vast majority of us have no need to change anything but there’s a few who would benefit from being able to fly slow and a lower AOA.

We had a conversation about this last year I think. I nerded pretty heavily over it and came up with what I felt like was a pretty simple solution to install a dropped hinge slotted flap..
It’s been a year and I kept bad notes so I’d have to do an in-depth review to recall specifics. At this point I can’t accept taking the plane out of service for something I don’t need.
 
Nev said:
This is a very interesting discussion.

I'm curious - what issue would be solved by changing the flap design ? Where is the Bearhawk falling short ? Does it need to land slower ? Shorter ? Fly the same approach speeds with more control ? Better "over the nose" visibility ? I've yet to fly a B model and mine will probably be the first that I get to fly, but I'm interested to see if the pitch sensitivity (and pitch trim sensitivity) from the servo tab is still present in the B model.

My point being is that I wonder if there are lower hanging fruit on what is already well proven aircraft before getting into more complex areas such as the flap design. Examples that come to mind are reducing the pitch sensitivity, and increasing pitch control at forward CG/low speeds, ensuring that adverse yaw is limited through correct rigging during test flying, lowering flap bar forces etc.

On the other hand, if it's a case of doing it because it's an experimental aircraft and we need a project, then bring it on !
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The plain flap doesn't make much lift. It's the least effective of all flaps designs, and it's also the simplest. It also doesn't make much more lift at a reduced AoA. Which is the entire purpose of flaps. To be able to make X lift at a lower AoA. If we didn't care how high the AoA was on landing, you'd see slats on everything instead of flaps. Plain flaps do make a lot of drag, which is sometimes desired.

There wouldn't be a massive decrease in stall speed with any of the improved designs. There would be a rather large decrease in ref speed. There would be better over the nose visibility and the ability to fly at slower speeds and touch in the 3 point or 2 point attitude. A max performance landing right now is always a tailwheel first landing.

That all said if you're not using all the performance your bearhawk is capable of and landing off airport at short strips, there's no realistic gain to be had. If you're flying even fully loaded out of 1000ft of grass, there's nothing to be gained. You can just come in at 55 or 60kts and have all the visibility and 2 point landings you want and still not come close to using that runway up.
 
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That all makes sense.

Out of interest, do you guys normally land with full available flap ? I'm wondering what effect it would have if you flew an approach a few kts faster, with full flap so that the drag took care of the extra speed on round-out. Clearly a work-around. But would the few extra kts lower the approach attitude and increase over-the-nose visibility ?
 
Nev said:
That all makes sense.

Out of interest, do you guys normally land with full available flap ? I'm wondering what effect it would have if you flew an approach a few kts faster, with full flap so that the drag took care of the extra speed on round-out. Clearly a work-around. But would the few extra kts lower the approach attitude and increase over-the-nose visibility ?
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Yes, and that's generally what you have to do. The faster you fly, the lower AoA you can fly for a given weight. But energy is mass * velocity^2.
 
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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 the reduction in tail incidence), and a favorable change in already good stall characteristics. There's nothing wrong (and plenty good!) with the Model A, but the B is "slightly better." Why not try? It's Experimental, it's fun to try something new if it doesn't kill you in the process. But, if you have a flying plane and don't want the down time, or you just want to get your build in the air, keep with what's been proven.

I think the improvement in stall speed with a slotted flap would be small, but noticeable, and would also help with the deck angle when flying very slow. It would also improve roll control slightly, but again, with the current slotted aileron design, there may little, if any, noticeable improvement. I estimate that the Bearhawk plain flap improves maximum section lift coefficient by about 20-25%; a good slotted flap design could probably double that. It may sound like a lot, but stall speed will go with the square root of the ratio of lift coefficients. So, if I WAG our unflapped airfoil as having a Cl of 1.7 (about what you'd see with a NACA 4412 at this Reynolds number range), a plain flap may be about 2.1, and a slotted flap would be about 2.5, giving the plain flap a stall speed improvement of sqrt(2.1/1.7) = 1.11 (~11% reduction in Vstall) for that section; the slotted flap is then sqrt(2.5/1.7) = 1.21 (~21% reduction). That sounds like a lot, but only about 55% of the Bearhawk span is flapped. So if the outer section stalls at a Cl of 1.7, and the flapped section at 2.1 or 2.5, then, from a 2D flow perspective, the plain flap reduces stall speed by (0.55*1.11 + 0.45*1 = 1.06) about 6%, and the slotted flap by about 12% (or, conversely, a 6% reduction in stall speed from the plain flap). If your unflapped stall speed is 50 knots, that logic says your plain flap stall speed is 47 knots, and your slotted flap stall speed is 44 knots. (All speeds are notional, I don't want to get into a stall speed war at this time. Point is, you're talking *at most* a 6% and 12% reduction in stall speed vs. unflapped for plain and slotted, respectively.)

Reality won't even be that kind, because that assumes you are hitting maximum lift on both the unflapped and flapped portions of your wing at the same time, and have no 3D losses (vortex at the wingtips or from the flap tip, uneven downwash distribution, etc.). Since the slotted flap will hit maximum lift at an angle of attack that is lower than the unflapped portion with the aileron (which is also slotted, but it won't be deflected as much as the flap unless you're in quite a crosswind!), the aileron portion of the wing won't be at maximum lift when the flapped portion is. However, what you will notice is the potential for a lower deck angle and slightly better aileron effectiveness, since the aileron portion of the wing won't be as close to stall.

I'm attaching the following picture (not copyrighted) from Aerodynamics for Naval Aviators; a great, practical reference for aerodynamics if you haven't seen it: https://www.faa.gov/regulations_poli.../00-80t-80.pdf. I think it under-represents what you can get from a thicker basic section, but the trends are all good.

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The high nose angle is reduced by about 50% by a trailing edge lift device, this has been proven by a Utah pilot with a 4 place.
Stall speeds about 2 kts slower.
Stable approach speeds 4 to 5 kts slower.

The nose angle is the main thing - you understand this Nev :)
 
I'm about ready to cover (which for me is the last part of the fuse), but it's getting to be winter, so I have to wait until spring. Now it's on to firewall forward or wings. I think wings because I don't want to do firewall forward then remove it for the rotisserie. Maybe in the next few weeks I can mock up some lowered flap hinges.
 
Not only that, I have a full autopilot setup which can control the trim servos. This means my AP can trim my airplane. Also, there is a bearhawk flying like this already, it works just fine.
 
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I checked the flaps on a friends Husky yesterday, the hinge point is moved forward as well, which lowers the flap as it is deployed, to bring the airflow over top. I'm not sure if the Maule hinge point is moved forward or just down.
 
It's probably a trade-off, if the hinge is aft then the flap moves rearward, which is good. If the hinge if forward, then the flap moves downward, which is good. NACA determined something along the lines of, the best gap size to maximise lift is 2% cord. So that needs to be factored in as well.
 
Hi guys

I am just at the beginning of my project, nothing done on the wings yet, i'm from Canada and what i need is a decent bush machine, i seriously considering building my Bravo wings at 36 feets,
so longer flaps and longer ailerons, it will be on amphib floats so i will loose on top speed to begin with, since i'm not an engineer, even less any big knowledge in aerodynamics, i think i will just keep the proportion of the ailerons and the flaps lenghts of the standard Bravo plan, however, i am very tempted to modify the flaps a little bit and make thems more like the Husky ones, i have
found a design online that is quite interesting and i think it can easily be adapt the Bravo wings, i'm a former machinist and i have a lathe and a milling machine in my garage, i can make the necessary parts myself.

Check it below and let me know what you think.

Franky
 

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Have you considered adding wider Horner wing tips, rather than building longer wings, it would be a lot easier.
 
Yes the Husky flaps are differents and much simpler, the similaritee is that they open lower like the ones above, i see the ones above as acting a little bit like the double slots flaps, for sure not as efficient but much less easier to fabricate.

Adding a longer wingtip will give you more wing area but will not decrease the stall a lot, improving the flaps will do much more for reducing the landing distance, my wings are not built yet, i have a set of 17 feets spars that i'm planing to use, they were made for a beef up Super cub (see below) so not much work for me the make a longer wing, the other thing is that i'm a garage guy, and i enjoy building things.
 

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I think you are underestimating the level of engineering that this mod is going to require, all the while solving a problem that isn't a problem.
 
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Franky139 said:
Hi guys

Check it below and let me know what you think.

Franky
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Franky;

Here is what I think.

Experimentation is exciting to me. I really look up to fabricators! You guys build really efficiently. I mean fast and good. I see industry best practices come from Fabricators. Being a machinist/fabricator you have decades of skills, background, tools, to visualize and build. Retirement.....now its time to experiment on fun stuff!! I'm curious what you will find out.

I think you see a lot of good stuff in the Bearhawk Wing design. I think a flap with some fowler action would improve it. I like the Cessna flap action but your drawing is innovative!

It seems like the dimensions of your spar webs will allow you to design a new wing. The flap you designed plus your spars moves the wing away from the Bearhawk prints so this will be your wing, not a modified Barrows Wing. I'm thinking a new flap design would produce different (higher) loads on the rear spar. So thats an engineering problem to investigate, measure, build and break so determine streangth needs.

The Barrow Wing on the Patrol, Modle B, Companion and Five has a main spar dimension of 8.25". Thats about 1/3 thicker than your spar. We get good speed with that thick Riblet Airfoil. That kind of jumped out to me.​​

I highly respect what Jared said. Are you a designer, builder or flyer? There are enough Bearhawks on floats to determin if the stock wing will meet your expectations. But that might not meet your goals if you are a designer.
 
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Guys

You are all right in yours comments and they are welcome, i should have start by telling you who i am: helicopter and fixed wings pilot with ATP licences, 18600 hrs of flying, first job was as a machinist, i became a pilot a few years later, i have built a Cyclone airplane in the 90's, it was a copy of the old Cessna 180 in kit form, the main difference was an extra foot of wing at the
root, giving us an extra foot of flap, we also add a cuff on the leading edge wich was a copy of the Horton stol kit at the time, theses mods made a big difference we could take off in about 200 to
300 feets depending on how loaded we were.

I'm half retired, i still fly helicopters on a contract basis and building another airplane is my retirement project, i have a Citabria fuselage and the set of spars mentioned above, In canada, we can used an existing fuselage for a project, as long as we comply with the 51 % rules, my first idea was to build a Super Cub wing or buy the Ribletts ribs made by D&E Aircraft in Florida but when
i've heard about the Bearhawk Patrol and the performance that they were getting with it, i tought myself: This it, i will put this wing on the Citabria so here i am,

My best buddy's son is an aircraft engineer (a real engineer, not just a mechanic) he can do the necessary structural analysis for me, i can do most of the necessary parts with my lathe and my milling machine, i' guessing you all know Mike Patey with his Draco and Scrappy airplane, well, i'm a bit like him, but without the big wallet and the CNC equipments.

I'm not 100% in that project yet, this is why i'm here to get as much positive or not so positive comments before jumping into it.
 
Don't forget the crew he has working on his stuff for him day in and day out. It's not just about the $$ and equipment. One person cannot do what he does in the time he does it.
Good luck with mods!
 
Hey Bobby, did you manage to get a slightly lower stall speed with power on ? I found mine was losing elevator authority at CG forward of 15 inches. I could get it to stall just around 38 KTAS at light weights and forward CG (F3 or F4), by keeping power on. The power on gives airflow over the elevators and keeps them active, allowing the wing to stall first. If the CG is aft of about 15 inches, then the wing will stall first with power off.
 
Nothing is done yet , i'm still looking, thinking and evaluating, the other thing is weight, 1350 lbs is my maximum for empty weight with an angle valves on the nose.

Franky
 
Wow, right on Brooks! people forget the Bearhawk only has one wing strut. The loading on the aft wing spar and ribs with flaps is significant. Yes the skin and ribs are carrying a lot of the twisting motion to the main spar. One Strut . Stinger
 
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