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BH-5 Specs wanted

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  • Bearhawk Five BH-5 Specs wanted

    I’m looking for some detailed specs on the model 5 with 300+ hp engines. How many are built and flying already?

    I spoke a few times with the kind folks at the Bearhawk exhibit last week at OSH and asked a lot of questions. I have come up with a few more since, and want to also get some detailed real-world performance numbers, especially at higher altitudes. It sounded like there had not been any real testing done above 5,500’ on the prototype yet. I’m not a fan of low-altitude cross country flying, for several reasons, namely safety, efficiency, smooth air. I know most airplanes get the best cruise speed at 75% power in the 7 to 9,000’ DA range, and some are still close to those speeds in the low teens but with much lower fuel burn. My Twin Comanche is one of those, and I like cruising in the 9 to 15,000’ range, depending on winds. I lose at most 4 knots of TAS, but fuel burn drops 23% from 8 to 12,000. Some other airframes are not this way, and don’t cruise worth a darn up high.
    Could I expect 150 knots+ at 8,000’ +/-?

    Is there anything that can be done to make it a more speedy airplane and less of a STOL airplane? Such as aileron and flap reflexing, small tires with wheel pants, fairings, modifying to do away with the tail braces, etc? Has anyone built one while focusing on these sorts of things, and if so, what are the best cruise numbers? I do fly off a farm strip, but it’s 2,700’ with no obstructions.

    Is 1500 lbs useful load pretty realistic for an IFR equipped airplane if I’m conscious not to make it a heavy pig? Would there be any basis behind making the gross weight higher than 3,000 lbs but restricting the landing weight to 3,000?

    Is the model 5 a stable airplane in roll and pitch? By this, I mean can you let go for 30 seconds and not change altitude or begin a turn in mostly smooth air?

    Is it pretty stable on the ground compared to other taildraggers? Especially when there is an aft loaded CG, it seems like it could potentially become somewhat of a handful on the ground.

    How much crosswind can it handle without being difficult to keep the wing down? The big wing and flaps seem like they would make it susceptible to strong or gusty crosswinds. I’m used to being able to easily handle 25 kt xwinds, and occasionally 30-35 if necessary.

    Has anyone come from flying airplanes with yokes and gotten tired of having a stick in the way for long trips? I like to have room to move my legs around and stretch on 5+ hour cross countries.

    Has anyone installed 4 25.5 gallon main tanks (104 total), using 2 of them as aux tanks instead of 25.5 gallon mains +11 gallon aux tanks (73 total)? What would be the limitations to do so? I’m not familiar with how the wings are assembled around the tanks.




    Last edited by Zac Weidner; 08-02-2022, 09:07 PM.

  • #2
    Zac, as the guy currently flying the prototype Mod 5, I'll answer a few of these and I'm sure Mark and the rest of the pros from Dover will chime in with the rest.

    The prototype is still the only Mod 5 flying, but I know that will be changing soon....

    Regarding the 75% cruise performance up high, I personally have had it at 9500', just wasn't paying attention to cruise numbers. I'll get some numbers for you (and everyone else) the next time I take the airplane up.

    All trimmed up in smooth air, I can put my feet on the floor and just fly with 2 fingers. I don't know that I could let go for 30 seconds and have zero turn, but it will certainly maintain altitude.

    I would describe it as extremely well mannered on the ground--it really is an honest tailwheel airplane.

    Also a very strong swimmer in crosswinds. I've landed in an 18G27 direct xwind with no issues. Others who have flown the prototype may have seen more.

    i've flown numerous airplanes with both sticks and yokes. Never had an issue with either--only felt restricted if there was a center console/divider in the way.

    Ryan

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    • #3
      Ryan, would it be possible to do some flying with you in the prototype to get a feel for it and go more into depth with a few things? I know I am asking a lot of questions. I am just trying to make sure I don’t spend a couple of years building a project to make it just right, only to be disappointed with the mission it suits. I love flying and also know I am going to have just the right airplane to be able to make myself sell our Twinco that we’ve had for 50 years. We don’t have room or funds for all 3. I’m thinking that the BH would be much more economical to maintain in the long run with 1 engine instead of 3, and fixed gear, etc.

      Another data point I would be interested in, as I am sure other also; how slow can you reasonably putt around with the BH5 lightly loaded (1-2 people and moderate fuel load), and how low is the fuel burn leaned out at that speed, maybe even with a notch of flaps in? 60 MPH? I like to putt around to look at crops and sightsee locally, and would love to still be able to go flying for 30 minutes or so on just a few gallons. The Tripacer does this very well now for me at about 4.5 GPH, Twinco not so much.

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      • #4
        Zac, sent you a PM re flying the prototype. As to the low and slow capabilities, I'll give you another "There I was...". Coming home from OSH on Sunday I paired up with a Cessna 170 driver who had gotten stuck in MO for WX on Saturday. To stay with him, I was burning 8.9 gph (38-40% power) and showed an endurance of almost 6 hours on the JPI after leveling and leaning out. That was ~18 MAP and 2300 RPM. you could certainly dial it back more for just some 'Sunday cruising'.
        Last edited by flashf16; 08-06-2022, 07:09 AM.

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        • #5
          Regarding the ballast that’s needed-have you considered adding something like a water ballast near the tail wheel? That would require only approximately half the weight, and could be drained on the ramp if, for an example I thought of, I were to fly somewhere solo to leave from there with a gross weight loading. Either that, or a 15 gallon tank in the tail that could be transferred to the mains in flight or on the ground if there is sufficient weight in the tail.

          Another thought, could the center of lift be moved forward slightly by reflexing the flaps a few degrees, thus allowing for a more forward CG limit?

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          • #6
            Zac, I think you would be well served to call Bob. He is super approachable and has all the answers to any questions you have regarding CG’s and loading.
            N678C reserved
            Revo Sunglasses Ambassador
            https://www.youtube.com/channel/UCQ0...tBJLdV8HB_jSIA

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            • #7
              Agreed—I would defer to Bob

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