  
       
       the 
                                          Barrows Bearhawk 
                                          
       by Budd Davisson, courtesy of 
       www.airbum.com
                                          In recent 
                                          years we've seen utility come to the 
                                          fore in many of the new kit designs. 
                                          However, with a few exceptions, all of 
                                          the offerings have defined utility as 
                                          being two-people carrying only what 
                                          they need to get by. This utility has 
                                          also been available only in kits, so 
                                          the price of entry is daunting to 
                                          some. 
                                          And then there is 
                                          Bob Barrow's scratch-built, plans 
                                          offering, the Bearhawk. Bob defines 
                                          Utility as an airplane with few 
                                          limitations in the way it is used. 
                                          This includes four full-sized seats 
                                          (the cabin is the same size as a 
                                          C-172), 1200 pounds useful load, 55 
                                          gallons of fuel standard, and the 
                                          ability to hang anything from 150 to 
                                          260 hp in front of the firewall. Now 
                                          that's a usable airplane. 
                                          Barrow's airplane 
                                          is also unique in today's homebuilt 
                                          environment, where the predominant 
                                          thought pattern seems to be 
                                          build-it-fast-and-don't-worry-about-the-cost, 
                                          because a) it is only available as 
                                          plans and b) it emphasizes simplicity 
                                          and low cost.  
                                          
                                            
                                          
                                          The cost 
                                          of entry required to build Bob's 
                                          130-150 mph, 
                                          carry-anything-and-land-anywhere 
                                          airplane is the two hundred bucks for 
                                          the plans. Past that, you can spend as 
                                          much as you like, when you like, as 
                                          fast as you like. That's the beauty of 
                                          scratch built airplanes. You can spend 
                                          a couple hundred bucks on aluminium 
                                          and start hammering out ribs, or drop 
                                          a much larger bundle for the entire 
                                          bill of materials, which in the 
                                          Bearhawks' case is estimated at under 
                                          $6,000, which includes everything (as 
                                          in everything!) with only the engine 
                                          and prop to be add. 
                                          Bob did not start 
                                          out to design an airplane to sell. In 
                                          fact, the Bearhawk was originally a 
                                          project meant to fill his own needs 
                                          for utility in his airframe and engine 
                                          building business. But, we're getting 
                                          ahead of ourselves. 
                                          First, it is 
                                          necessary to understand Bob Barrows 
                                          and how he came to be sitting under 
                                          his airplane at Oshkosh answering a 
                                          million questions about his obviously 
                                          useful airplane. 
                                          Bob has been a 
                                          practicing mechanical engineer for 
                                          nearly thirty years which included a 
                                          long stint as Manager of Engineering 
                                          for one of Ingersoll-Rand's facilities 
                                          in Virginia. However, that was only 
                                          one part of his dual life. Outside the 
                                          office, he had developed his own 
                                          little airport, where he built 
                                          airplanes and re-built engines. 
                                          Initially, he built 
                                          a Midget Mustang, then designed and 
                                          built his own STOL, single place bird 
                                          he called the "Grasshopper." He flew 
                                          that for 15 years before parting with 
                                          it. Then there was a 260 hp, 
                                          symmetrical-everything, Pitts type 
                                          aerobatic machine. And an RV-3. And a 
                                          couple of rebuilt projects. 
                                          
                                          
      
                                          
                                          
                                            
                                          
                                          
                                          By 1980 
                                          his engine business was picking up and 
                                          he began to feel the need for a 
                                          utility type airplane and he began 
                                          work on what he then called the RB-4, 
                                          which was renamed Bearhawk. 
                                          "I got some parts 
                                          finished, spars and ribs and such, but 
                                          then I decided I needed a four-place 
                                          airplane for the business right then 
                                          and bought a rag-wing, Cessna 170 
                                          project." 
                                          The Bearhawk 
                                          languished in the backwaters of his 
                                          project ladened shop until he decided 
                                          to leave Ingersoll and strike out 
                                          freelance in 1988. 
                                          "My engine business 
                                          was doing well, so I wasn't afraid of 
                                          being out there on my own." 
                                          Confident words 
                                          from a man with a wife and four kids. 
                                          It was at that 
                                          point he decided to finish the 
                                          Bearhawk which took "...oh, I don't 
                                          know, a year or two..." He acts as if 
                                          building an airplane is a monthly 
                                          occurrence on his little strip. 
                                          
                                           
                                           
                                          
                                          Which 
                                          brings us up to Oshkosh '95, by which 
                                          time he had been using the airplane 
                                          for several years in his business. Bob 
                                          makes no bones about the fact that his 
                                          airplane is a working airplane. Not a 
                                          show winner or a machine designed to 
                                          blaze cross country in formation with 
                                          the composite crowd. However, whenever 
                                          we walked past the airplane on the 
                                          flight line, there was always a number 
                                          of folks asking questions or hanging 
                                          their heads down in the cockpit to see 
                                          how this or that was done. 
                                          The airplane was of 
                                          interest to a lot of people because it 
                                          was an airplane that makes a lot of 
                                          sense. Which is exactly the reason I 
                                          was attracted to it. It makes so much 
                                          sense in so many different ways. 
                                          Bob is one of the 
                                          friendly, more soft spoken types 
                                          you'll find and was quick to agree to 
                                          a flight. He is also just looking for 
                                          an excuse to go flying. 
                                          While we were 
                                          waiting to pull out from the flight 
                                          line, I spent some time looking the 
                                          airplane over. The wings are all 
                                          aluminium and many of the details, 
                                          Barrows is quick to point out, lean 
                                          heavily on Midget Mustang/RV 
                                          technology. This is especially evident 
                                          in the spars, which are "C" shaped 
                                          .032" channels with 1/8" x 1 1/4" 
                                          straps of varying lengths riveted to 
                                          the web face inside the flanges. The 
                                          straps are stacked in varying depths 
                                          and lengths depending on the stresses 
                                          and are centred on the outer strut 
                                          attach point rather than all eminating 
                                          from the root as with cantilever 
                                          designs. 
                                          The flaps and 
                                          ailerons are all aluminium framing 
                                          with fabric cover and hang from the 
                                          rear spar, which Barrows says is 
                                          heavier than normal for that reason. 
                                          The ailerons hang on long, tubing 
                                          weldments which form tripods bolted to 
                                          the rear spar. The flaps, which extend 
                                          all the way out to 50°, are simple 
                                          hinged affairs. Bob says he considered 
                                          Fowlers but opted for hinged flaps 
                                          because of their simplicity and small 
                                          trim change when deployed. 
                                          The ribs are all 
                                          hand formed over wood forming blocks 
                                          with no stretching done. Instead, they 
                                          are partially bent over the forms, 
                                          then the flanges hammered to 90° while 
                                          off the form. The resulting distortion 
                                          in the rib is removed by fluting the 
                                          flange between the rivets. 
                                          The entire control 
                                          system, elevator and flaps included, 
                                          uses cables and pulleys rather than 
                                          push rods, although bellcranks do move 
                                          short pushrods to activate the 
                                          ailerons. The bellcranks and final 
                                          pulleys mount on steel tubing 
                                          weldments bolted between the spars. 
                                          
                                           
                                           
                                          
                                          The 33 
                                          foot wings are skinned in .025" 
                                          aluminium and use bucked or squeezed 
                                          solid rivets throughout. 
                                          The struts are 
                                          aluminium and Bob says the best source 
                                          for them is damaged 180/182 Cessnas. 
                                          His are four inches shorter so struts 
                                          with broken forks can be salvaged and 
                                          used. 
                                          The fuselage is 
                                          good, old-fashioned steel tube, which 
                                          Bob used for a reason. 
                                          "From an 
                                          engineering standpoint, steel tube is 
                                          easy to analyze and the calculations 
                                          are reliable," Bob explains. "It also 
                                          offers excellent protection in case of 
                                          an accident and is easy for the 
                                          homebuilder to build with a minimum of 
                                          tools and jigs." 
                                          In reviewing the 
                                          plans, I found nothing in the fuselage 
                                          that was even remotely difficult or 
                                          unusual. In fact, the main wing 
                                          fittings nest a "U" shaped fitting 
                                          inside the usual blade-type fitting 
                                          which not only gives additional area 
                                          for bearing strength without welding 
                                          across the load path, but gives a huge 
                                          amount of weld length so the quality 
                                          of the weld becomes less critical. 
                                          There is a lot of this kind of thought 
                                          through out the airplane. 
                                          Because the 
                                          fuselage changes cross sectional shape 
                                          quite often, it looks as if it is 
                                          going to be one of those fuselages in 
                                          which the top and bottom trusses are 
                                          built first, then jigged into position 
                                          and the side pieces added. 
                                          The most complex 
                                          pieces, actually the only complex 
                                          pieces, are the Maul-type oil-spring 
                                          shocks in the landing gear. Those will 
                                          require a little machine work but the 
                                          result is an aerodynamically clean 
                                          shock system which doesn't take up any 
                                          cockpit space. 
                                          When the cowling is 
                                          opened the first thing you'll notice 
                                          is the huge amount of space behind the 
                                          engine. There's at least a foot of 
                                          empty space! But, when there's a 260 
                                          Lyc under the hood, that's where the 
                                          extra set of cylinders go. The 
                                          propeller stays in the same position, 
                                          so the cowing remains unchanged 
                                          regardless of which engine is used. 
                                          The only changes necessary are putting 
                                          the battery behind the huge baggage 
                                          compartment rather than on the 
                                          firewall. 
                                          The nose bowl, 
                                          incidentally, is a Pitts Special unit. 
                                          When poking around 
                                          under the hood on Bob's personal 
                                          Bearhawk, you'll also notice there is 
                                          no starter or alternator. One of his 
                                          friends says Barrows is allergic to 
                                          electricity. 
                                          When we finally 
                                          found ourselves out on the taxiway and 
                                          saddling up and I was delighted at his 
                                          door arrangement. First of all, there 
                                          is a door on both sides and the bottom 
                                          half hinges forward, while the top 
                                          half is hinged to the bottom of the 
                                          wing like a Cub. This makes it 
                                          practical to taxi or fly with the 
                                          windows open and your elbows on the 
                                          door sill like you were cruising the 
                                          drive-in on a Saturday night. 
                                          The cabin is also 
                                          extremely tall and full of light, 
                                          rather than being dark and crowded 
                                          feeling. The seating position is very 
                                          Cessna in its approach, a fact which 
                                          allows the builder to use a modified 
                                          Cessna 172 windshield on the Bearhawk. 
                                          Both the front and back seat room is 
                                          the same as the Cessna 172. 
                                          Bob has no seats in 
                                          his drawings, but adapts existing 
                                          seats and tracks to his airframe. His 
                                          machine uses Tri-pacer seats. 
                                          
                                          
                                          If I had 
                                          a complaint with the airplane it was 
                                          having to fly on the left side with a 
                                          right hand throttle. Yeah, I know, you 
                                          should be able to fly either way, but 
                                          having a control stick in the left 
                                          hand and a throttle in the right just 
                                          doesn't seem right. 
                                          In taxiing, a 
                                          slight stretch lets you see completely 
                                          over the nose, which isn't really 
                                          necessary but makes it nice, 
                                          nonetheless. A little brake was 
                                          necessary for taxi because the 
                                          tailwheel springs were extremely 
                                          loose. 
                                          I glanced up at the 
                                          trim, which is a Cessna-type wheel 
                                          mounted in the ceiling, satisfied 
                                          myself it was where Bob recommended, 
                                          and started the throttle in. The 
                                          engine in Bob's airplane is an 0-360 
                                          set up for mo-gas which he figures 
                                          gives about 170 hp. As the throttle 
                                          went in and the constant speed prop 
                                          began biting in, the airplane 
                                          literally lunged forward. I'm a real 
                                          fan of machines that start pumping 
                                          adrenaline right from the starting 
                                          line and this is one of them. What a 
                                          delightful monster this thing would be 
                                          with 260 hp! 
                                          Bob recommended 
                                          that I don't force the tail up but let 
                                          it come up on its own, which worked 
                                          nicely and almost as soon as it was 
                                          up, the airplane left the ground. 
                                          Actually, it didn't just "leave" the 
                                          ground. That's too simplistic. It 
                                          acted as if the landing gear and the 
                                          ground were like-poles on magnets and 
                                          the airplane was repelled away, it 
                                          separated so cleanly. The takeoff 
                                          happens so quickly, there's little or 
                                          no time to analyze what it is doing 
                                          directionally. But whatever it was 
                                          doing took only a tap here and there 
                                          to keep the centreline where it should 
                                          be. 
                                          Considering that we 
                                          were in a four-place airplane, the 
                                          initial rate of climb was almost 
                                          startling. It immediately started up 
                                          at around 1,300 fpm. With a 180 hp 
                                          engine the powerloading at gross would 
                                          be about 12.8 lb/hp which is quite 
                                          respectable but with a 260 hp, it 
                                          would be 8.8 lb/hp which puts it in 
                                          the skyrocket category. With two 
                                          people and half fuel, it would be 
                                          around 6.5 lb/hp which is right up 
                                          there with the serious aerobatic 
                                          specials. What a kick that would be! 
                                          We arrived at 4,000 
                                          feet in nothing flat and I put the 
                                          nose down setting up a 23 square 
                                          cruise which eventually settled out at 
                                          about 120 knots, or 135-138 mph. Which 
                                          brings us to one of the points I liked 
                                          best about the airplane: It is ready 
                                          made for doing all sorts of little 
                                          homebrewed mods, beginning with 
                                          milking more speed out of it. The 
                                          wheels and brake assemblies could be 
                                          faired and an easy 3-5 mph added. 
                                          Strut fairings and control surface 
                                          seals might be another 3 mph. Engine 
                                          cooling another few knots. 
                                          
                                            
                                          
                                            
                                            
                                          
                                          
                                          
                                          The airplane's lines are quite clean 
                                          to begin but Bob's goal was utility, 
                                          not speed. Still, the homebuilder 
                                          could do little clean-ups here and 
                                          there and net at least 8-10 mph at 
                                          cruise. With the bigger engines there 
                                          is no reason this thing shouldn't be 
                                          cruising at 155-160 mph, or even 
                                          higher, at altitude. 
                                          
                                          
                                          In cruise the 
                                          visibility is tremendous. The nose is 
                                          well down and the glass area is just 
                                          about right for maximum vis. Those who 
                                          are heavy into bush flying or sight 
                                          seeing might want to skin the doors in 
                                          Plexi. 
                                          The aileron 
                                          pressures are Cessna/Piper-average 
                                          with a reasonable break-out forces and 
                                          the roll rate is probably about 
                                          70-80°/sec, which isn't lightning 
                                          fast, but about what you'd expect for 
                                          an airplane of this type. I'd be 
                                          tempted to gap seal the ailerons for 
                                          increased rate and either go for 
                                          spades or move the aileron hinge point 
                                          back a little to lighten them up. 
                                          Don't construe this to mean the 
                                          ailerons are heavy, because they 
                                          aren't. It is just that my personal 
                                          taste is for lighter, quicker 
                                          ailerons. 
                                          As it is set up 
                                          now, the elevator is matched to the 
                                          ailerons but the rudder is relatively 
                                          light and tremendously powerful with 
                                          only a hint of break-out force, so 
                                          coordinating at first takes a little 
                                          practice to keep the ball in the 
                                          middle. 
                                          Even before we got 
                                          in the airplane Bob said he was still 
                                          experimenting with various details, 
                                          one of which was the stabilizer 
                                          setting. In doing stability tests we 
                                          found the airplane would begin to 
                                          return to neutral if pulled off trim 
                                          speed (statically positive) but then 
                                          it would begin to gain speed and 
                                          wouldn't level out as the speed built 
                                          up (dynamically neutral). We discussed 
                                          this in some detail and after Oshkosh, 
                                          Bob called to say he had changed the 
                                          stab setting by 2° and it had a marked 
                                          effect on the same tests. Now it was 
                                          dynamically positive and if pulled 10 
                                          knots off trim would gain less than 10 
                                          knots on the initial down line and 
                                          would damp out entirely with no 
                                          phugoid remaining in three cycles. 
                                          We wandered over to 
                                          an outlying grass field and set up to 
                                          shoot some landings. As I made the 
                                          first power reduction opposite the 
                                          end, the airplane's basic clean lines 
                                          were obvious in the way it held on to 
                                          its speed. It took more work than 
                                          you'd expect for an airplane of this 
                                          type to get down to the flap speed of 
                                          80 knots. 
                                          The first landing 
                                          was made with half flaps at an 
                                          approach of 60 knots which Bob says he 
                                          recommends for the first few landings, 
                                          although he's perfectly happy using 45 
                                          knots. The first landing was a 
                                          non-event because the airplane settled 
                                          on in an effortless three point and 
                                          rolled straight ahead for a short 
                                          distance before stopping on its own. 
                                          Then I started 
                                          playing with full flaps and lower 
                                          approach speeds and found it took a 
                                          little more technique. With 50° of 
                                          flap, the airplane is really nose 
                                          down, so with only two of us in the 
                                          airplane it was fun trying to get the 
                                          tail down at just the right moment. 
                                          Power-off with the CG that far 
                                          forward, there wasn't quite enough 
                                          elevator and I'd touch main gear first 
                                          with the expected hippity-hop. The 
                                          preferred approach would be slower, 
                                          with just a little power to keep the 
                                          elevator working. 
                                          When we were all 
                                          done flying and I was sitting around 
                                          with a Delta Charley (diet cola) 
                                          thinking about it, I found there was a 
                                          lot about the Bearhawk which I found 
                                          wildly attractive. In fact, given the 
                                          opportunity, I could actually see 
                                          myself building it. In the first 
                                          place, it's no secret I love bush-type 
                                          aircraft. So that's part of the 
                                          airplane's attraction. 
                                          I also love the 
                                          basic simplicity of the airplane and 
                                          Barrows straight ahead approach to 
                                          design. He doesn't complicate anything 
                                          and, because of that, it is easy to 
                                          see how things work and how to 
                                          fabricate them. 
                                          I was thumbing 
                                          through a couple of back issues of his 
                                          quarterly newsletter, Bear-Tracks, and 
                                          found yet another reason I like the 
                                          airplane: His straight-up design 
                                          approach is followed by a similar 
                                          philosophy in supporting his builders. 
                                          He doesn't waste a lot of time and 
                                          effort in designing brochures or fancy 
                                          graphics, he just gives the builder 
                                          totally understandable directions on 
                                          how to build things with a minimum of 
                                          tools. What he doesn't do in gloss and 
                                          colour, he more than makes up for in 
                                          clarity and understanding. The 
                                          newsletter presents a lot of neat 
                                          building tips. 
                                          The drawings 
                                          themselves are professional looking 
                                          blue-lines and show his background as 
                                          both an engineer and long-time 
                                          airplane builder. 
                                          And then there is 
                                          one of the other points about the 
                                          Bearhawk which is attractive: It is so 
                                          simple and well done that it makes a 
                                          flawless platform for someone who 
                                          wants to incorporate their own ideas 
                                          in cosmetics, streamlining, interior, 
                                          etc. 
                                          For those who are 
                                          afraid of doing their own welding 
                                          (shame on you): Bob reports several 
                                          manufacturing shops have contacted him 
                                          about building component parts for his 
                                          builders. So there is help out there 
                                          for the faint of heart. 
                                          We haven't had many 
                                          four place airplanes offered to the 
                                          homebuilder in the past and none have 
                                          caught on. The Bearhawk looks as if it 
                                          should change that trend. After all, 
                                          think about its name: It's a Cessna 
                                          Skyhawk in concept with the brawn and 
                                          attitude of a Bear. Bearhawk. What a 
                                          combination! 
                                          
                                           
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