Source: 2019 Q3 Beartracks, Alan Arthur
The gliding fraternity have been talking about auto engine powered tugs for decades and despite the efforts of many they haven’t become a reality (yet), recent changes to Civil Aviation Safety Authority (CASA) regulations have made it a far more practical proposition.
A casual conversation around the bar lead to a syndicate being formed to look at a private venture to install a Mazda 13B Rotary engine in a PA 25–150 (small Pawnee). The syndicate members Alan Arthur, Doug Harrington and Avon Furphy conducted an extensive search for a suitable aircraft and finally dismissed the idea as too expensive, too much work, too many ADs and too many owners that had an inflated idea of the true value of their aircraft.
The idea changed to building a kit aircraft similar to a Piper Super Cub, also with a Mazda Rotary engine. The Bob Barrows designed Bearhawk Patrol was selected and after some consideration an order was placed for a Bearhawk Patrol quick build kit with Bearhawk Aircraft in Austin Texas. The kit was ordered in July 2016 and after a couple of months sorting out options arrived in Perth Western Australia on 29 December 2016.
A couple of days later after it had cleared quarantine/customs, a trailer ride to Narrogin saw it installed in the new hangar at the Narrogin Gliding Club for the build. The kit consisted of a steel tube frame and other welded steel tubes and fittings and lots of raw material. The instruction manual was quite basic but I purchased CDs of the build details compiled by other builders and the kit manufacturer provided hundreds of photographs of other builders projects. The basic airframe went together quite quickly and by the end of January 2017 we had the first visit from the SAAA TC Geoff Danes and the AP for the project Bill Keehner.
Avon already had a Mazda 13B engine sitting in his shed waiting for a racing car project so he donated it to the project, it hadn’t run for many years so was shipped to Rotormotion in Perth for a complete overhaul and conversion for aircraft use. Rotormotion’s brief included a target HP between 210-240 Hp.
The auto engine installation consumed enormous amounts of time as our glider towing goal meant that we could not have any problems with engine cooling at relatively low airspeeds and high power settings. Consequently we selected a twin radiator system and a double sized oil cooler. Experience during the test flying program indicates that we may have got it right.
Avon’s Mazda rotary engine was a fuel injected and electronic ignition version from a Mazda RX7. All of the Mazda fuel injection and ignition system was discarded and instead twin aftermarket EMS Stinger systems were installed driving the standard injectors and twin spark plugs. Also discarded was the heavy exhaust manifold and all the environmental systems. After initial engine runs the custom exhaust was modified to include two straight through mufflers and ceramic coatings on the engine pipes.
PSRU selection proved to be a bit of a problem, all of the toothed belt systems seem to have disappeared, the only system we could find with good reports was a geared system from Autoflite in NZ. This PSRU is available in two or three gear versions and we chose the three geared one to keep the direction of rotation the same as Lycomings. It also moved the engine thrust line up closer to the original design position. After selecting the PSRU then we were able to order a prop to match. We ordered an IVOPROP Corp Magnum three bladed ground adjustable prop of 76” diameter.
The fuel system needed to be modified to incorporate dual high-pressure injection pumps. Initially I was going to build a header tank with dual submerged pumps but in the end found exactly the setup I had planned in an auto supply catalogue at a much cheaper price. The system is now gravity feed to the header tank and high pressure to the injectors, return fuel comes back to the header tank.
The aircraft relies on electrical power for engine operation so it was quite critical that everything was duplicated; not only is everything from dual batteries to the ignition boxes selectable but we have incorporated a panic switch that can change all selections to the opposite selection with the flick of one switch. At higher altitudes you can do some fault diagnosis but when towing a glider at 100 ft you don’t have time to play around with systems.
The airframe is part covered with aluminium alloy and part with fabric; we chose to use the Oratex prepainted fabric. The Oratex fabric is quite easy to use and being prepainted has no hazardous solvents to use, the glue is a water based hot melt glue. The fabric is about 80% the weight of other fabric systems which resulted in the aircraft center of gravity being well forward requiring lead ballast in the tail. If I was to build another Bearhawk I would plan to fit the dual batteries in the rear fuselage and not on the firewall.
Instrumentation did not need to be very complex and other than the engine monitor all are round steam gauges. For the engine management system we used the MGL Extreme EMS display which has the advantage of being in the main programmable. After 19 months, 4450 hours and a lot of engine runs and taxi tests the big day arrived. Word had spread and instead of having a quiet first flight there were dozens of spectators on Saturday 15 September 2018.
The SAAA team arrived early for the final inspection, Geoff Danes and Bill Keehner did their inspections and Bill issued the Phase 1 C of A. The aircraft flies really well; it took to the air as if it was made to fly.
Alan also says: Dennis and Donna suggested that I also send you some photographs of my fool proof control lock (you can’t leave it in and go flying).
Fall 2019 Bearhawk News
Source: 2019 Q3 Beartracks
It has been a busy quarter for Bearhawk news! First, there is a new variant in the Bearhawk family, called the Bearhawk Companion. This is a side-by-side two seater that uses the same wings as the Patrol, with their low drag and stellar stall characteristics. The fuselage is based on the shape of the Bearhawk 4-Place, with certain tubes modified to reduce weight. There will not be a cargo door, and the maximum engine size is an 4-cylinder Lycoming type. The luggage area rear bulkhead moves forward one bay and the engine moves back 6 inches. Max gross weight will be 2200 pounds, up 200 from the Patrol, and 300 less than the 4-Place. Empty weight should be 1070+, 20 pounds more than the Patrol. This variant is inspired by customer requests, with the first two kits ordered and in production now. Plans will be available once they have been validated by the kit production process.
Mike Silvernagle has two interesting updates from Bearhawk Canada. First, he’s developing a variant to be called the Bearhawk Trek, which will be a Bearhawk LSA with a package of modifications so that it can comply with Canada’s Advanced Ultralight Aeroplane (AULA) rules. It has a gross weight of 1232 pounds and can be flown by any-one with an ultralight pilots license. Structurally, it is the LSA, but in Canada, any aircraft built light enough with a gross weight of 1232lbs complies.
Specifically for the Trek, but of interest to all LSA builders, Mike is working with ULPower on a complete firewall forward package. It will include the 130HP UL350IS engine, Whirlwind 3 blade prop, new motor mount, spinner and nose bowl. The UL350IS is 130hp and ends up 35lb lighter than the 100hp O-200. Other benefits of the UL include the single lever full FADEC and fuel injection.
If it isn’t obvious how busy Mike has been, he’s also been working together with Clamar to develop a bolt-on float and rigging kit for the Bearhawk 4-Place. He will be installing serial #1 of the new All electric Amphibs on a 4-place this winter and establishing a rigging kit that will have enough adjustment to make up for builder variances in float fittings. These floats are expected to be 30 to 35lbs lighter than a hydraulic system.
Updates from Bob:
Invitation to Bob’s Fly-in in Fincastle, VA, 10/19/2019
Bob and EAA Chapter 646 invite you to their annual fall fly-in at Barrows airport, VA04. Bob will provide the main course for lunch, and requests that guests bring a side dish as they are able. There is plenty of room to camp on Friday, and Bob’s big house is available for folks who want to bring a sleeping bag and camp indoors. Please let him know if you’ll be camping, so he’ll know how many to expect. Come see the prototypes for the Bearhawk 4-Place and Patrol, and hopefully a few other examples too. Save on shipping for Bearhawk parts that Bob sells, and maybe even a new Bearhawk hat.
It is worthwhile for all Bearhawk builders to visit Bob’s shop at least once, to understand the context of his design work. Getting There: Drive in via the beautiful Virginia countryside or test your flying mettle on the snugly situated backcountry runway. If you will be flying in, VA04 is at 37˚29.50N and 79˚ 55.70W, and Unicom is 122.8. If you can find it without using a GPS, you may consider yourself to a worthy navigator. The runway is short and narrow, and there are trees at both ends.
Driving directions to 2079 Breckinridge Mill Rd, Fincastle VA are as follows: Don’t rely on Google Maps, which may direct you to a river crossing without a bridge. From I-81 take exit 150B, US220N towards Daleville/Fincastle. Turn right onto US-220N, Roanoke Rd. Proceed north for 9 miles to Fincastle. Once in Fincastle, turn left onto Hernden St, which turns quickly into Grove Hill Rd. Take Grove hill for about 1.5 miles. Go over the bridge then turn left immediately onto Breckinridge Mill Rd. Continue for about two miles, then look left for the small “EAA” sign on a dirt road driveway that leads into the woods. If you reach camp Fincastle, then you’ve missed the driveway. The driveway is long and includes a low water bridge. As you come upon the row of hangars, find a place to park without blocking the road. The large hangar is the shop, which is where lunch is served. If you need help with directions, please call Bob at 540-473-3661.
Bob is getting around much better now, walking and driving. He took his car to a show and won Best of Show. He hasn’t been flying yet, based on concerns about the motion of his ankle. But he hopes to be back in the air as soon as he’s sure he can fly safely.
Bearhawks at Airventure 2019
Source: 2019 Q3 Beartracks
2019 was a great year for seeing Bob’s designs and their fans at Oshkosh! James Schrag sent these photos of Bill Anton’s yellow Bearhawk 4-Place, which won a Plans Outstanding Workmanship award.
Phil Johnson had his red and white Bearhawk 4-Place parked on the show line as usual, and Jon Middleton’s blue LSA was close by also.
Donna Svoboda’s Yellow Bearhawk Patrol and Dennis Reynolds’ Black Bearhawk Patrol were in homebuilt camping.
Rollie Vandorn brought his silver Bearhawk Patrol and flew demos in it, along with Mark Goldberg’s Bearhawk 4-Place Model B. The Bearhawk Aircraft booth included Mark Goldberg’s Bearhawk LSA, Ed Myers and Paul Nowaske’s yellow Bearhawk Patrol, and Cole Raiwet’s green Bearhawk 4-Place.
Chris Owens hosted a well-attended Bearhawk gathering, and there was a forum offered to introduce potential builders to the Bearhawk designs, hosted by Jared with some help from Mark Goldberg.
Spring 2019 News
Source: 2019 Q2 Beartracks
First flight of Joe Perdue’s New Patrol
Joe Perdue took delivery of a Patrol Quick Build kit in mid November 2018. It has been ready to fly for almost a month but weather and DAR delays have delayed first flight. On June 11th, just before dusk there was a break in the weather and winds so Joe got in 3 flights. He was really happy with how the plane flew. Very impressed with how the shock struts behaved on landing. More to come as Joe gets to fly his Patrol more.
We haven’t heard anything from Joe on the message board, but perhaps that’s how he was able to get the airplane flying in 7 months!
It’s Wintertime Somewhere
Murray Patterson sends this photo of his Bearhawk from New Zealand, which of course is experiencing its southern hemi-sphere cold season. He says: “This photo was taken of our Bearhawk ZK-FHR landing at 5000 ft on a snow groomed plateau. The strip is groomed as it is part of the Southern Hemisphere Proving Grounds (https://shpg.co.nz/) that are used every winter. Up to 40 companies come from the world over to test cars, SUV’s, tyres and other accessories. Each year at the end of the testing AOPA NZ have the opportunity to visit to land on one of the test areas. We can have 25 air-craft arrive with just one days notice.”
Bearhawk LSA Drawing
Jerry Cornwell sends this photo of a drawing of his Bearhawk LSA. It was selected for use as the background for the fly-in that is advertised in the foreground. Sounds like fun!
2019 Q1 News
Source: 2019 Q1 Beartracks
John Wheeler and his dad have been building their Bearhawk 4-Place with a Continental IO-360 engine. They are currently awaiting the DAR appointment to get the Airworthiness certificate. Weight came in just under 1400 pounds.
Ken Scott’s New Bearhawk LSA
Ken says: “I made the first flight of N112PR out of Dietz this after-noon. Ron Bourgeois and I each made two flights. Other than a pronounced reluctance to return to earth it flew well. The airplane is down right now to replace front crank seal, repair a carb heat cable support and re-pitch the prop. It’s been so cold in the hang-ar that none of us is anxious to work on it. It should fly again in a few days. My last 2500 hours or so is almost all in RVs, so I have a lot to learn about the BH.”
Ken wrote about his build experience in a series of articles in Kitplanes magazine.
Introducing Glen Phillips’s Bearhawk 4-Place
I got certification in December of 2017 but ran into a few glitches afterwards that took time to figure out. It seems every time the weather was good I found a problem with the plane that had to be corrected. I’m running one of Bobs 0-360s with a Prince P-tip climb prop. It climbs like a rocket. I put a GRT 7 inch glass panel in and I’m still trying to figure that out. I finally got some flying in late last summer and I’m about half way through my 40 hrs. testing. From my limited experience it flies great but a bit more than I’m used to so I’ll be glad to get in the air soon and work out some of my own bugs. Wisconsin Weather?
Larry Sullivan sends this stunning picture of his Bearhawk in the Wisconsin snow.
Bob Barrows sends the photo of his “new” car, a 1926 Buick.
Early 2005 Builder Updates
Source: 2005 Q1 Beartracks
Collin Campbell, #370, writes:
Bob,
Here’s some pictures of my completed project. 4 years and 10 months, a total of 2680 hours. I sure have enjoyed
the building process, many thanks to you for a good design and well drawn, easy to understand plans.
N370CC weighs 1321 lbs. This is with a Superior 0-360 engine, Hartzell constant speed prop, complete electrical
system, vacuum system with gyros, Com, GPS, Transponder with encoder, 4-place intercom, cargo doors, full skylight to rear spar, rear seat, modified doors with keyed locks, inertia reel shoulder harness in front seats, and a parking brake. I was pleased with the empty weight considering the equipment.
I am now awaiting the FAA to get down here to take a look at it. As you probably know they don’t get in any hurry. I plan to fly as soon as everything is in order and my 1300’ grass strip dries up a bit. Will let you know how it goes once I am in the air.
God bless,
Collin Campbell, #370
Completions: Curtis Penner’s Bearhawk Patrol
Source: 2018 Q4 Beartracks
All the Canadian airworthiness and registration is done, and I’ve put about 50 hours on the Patrol. Engine is an ECI Titan OX-360 w/ MTV-15-B/203-52 (80”) constant speed propeller. Includes Vetterman Exhaust w 2 Turbo heat muffs. Panel is 2-screen GRT Sport SX providing PFD, Graphical Engine Info, & Moving Map in interchangeable and/or split screens, Dynon D10A backup EFIS, GRT 4000 Engine Information system, Trig 21 transponder, Garmin 2 channel GTR200 VHF, GRT autopilot, iPad Mini for ADS-B & ForeFlight information, Appareo Stratus 2S ADS-B receiver. Extras: AveoMaxx 15 LED landing light. StolSpeed vortex generators, 21/800-6 main gear tires, 10” tailwheel.
Performance at 1200 lbs:
Will not give a stall break up to 3 notches of flaps. With full flaps, it will have a gentle break. Will remain controllable till airspeed indicator blanks out at 25 mph. Cruise at 135 indicated. (24”/2400rpm) Currently doing downwinds at 60 and 1 notch flaps, base at 50 and 2 notches, final at 40 and 3 notches, and touchdown at 30 and 4 notches. Takeoffs as soon as airspeed comes alive and climbs can be as steep (35 mph or as gentle 100 mph) as you like. Rolls easily with very little control pressure, but must lead with rudder, as there is a lot of adverse yaw. Once turn is initiated, rudder pressure not needed anymore until it’s time to straighten out again, when you again lead with rudder.
Note for Canadians…I had to insert shutoff valves between fuel tank and in-cabin sight gauges to prevent fuel leakage and subsequent fire hazard in cabin in case of failure. There is a fine wire (red) connected to quarter turn ball valve in wing to cut off fuel supply to gauge in case of leak.
Completions: Bill Anton’s Bearhawk 4-Place
Source: 2018 Q4 Beartracks
Airworthiness certificate issued on Tuesday Oct 31st by FSDO Wichita. 1st Flight was Friday November 2nd. Flight was take-off, very heavy right wing, climb to wide pattern, set up for landing and perfect landing until it became a little squirrelly thanks to my ham handed control. Looks like the right flap is a little high so will do so tweaking and try again. Also I’ll talk with Mark Goldberg for some ideas on how to correct it. Just a few details: 8 yr build, plans built wings, Bearhawk Aircraft fuselage, IO-540 engine, dual Light Speed ignition, dual batteries, Dynon Skyview touch avionics with some Garmin thrown in.
Completions: Rick Orchard’s Bearhawk Patrol
Source: 2018 Q4 Beartracks
Here are a few photos of the Patrol I finished in June of this year. I built it in 7 months and now have about 60 hours on it, mostly in the Idaho backcountry. I am based in Sandpoint Idaho and got a ton of advice and help from Ed Meyer. This was my sixth build and my most fun! I built a Murphy Moose with a PT6-20 turbine, a Lockheed AL-60 Grizzly, a Carbon Cub, and two Air-cams.
Completions: Greg Marlow’s Bearhawk 4-Place
Source: 2018 Q4 Beartracks, Greg Marlow
First flight for my 4-Place Bearhawk N22GM was November 7th, 2018, after 4 years exactly from receiving the QB kit. I had previously built an RV-9A and helped with a Rans S7S (which is for sale, btw). I was in a pretty severe motorcycle accident back in 2013 and lost my right leg. So getting in and out of the RV was going to be a problem, so I sold it and helped finish the Rans. I was able to pull myself up into the Rans with very little difficulty, so it fit the bill to get me back in the air. But, there was a problem. Because I don’t have enough muscle mass left in my right leg, I primarily use a wheelchair for my primary mobility. So flying anywhere besides local sight seeing, I needed to have crutches or ideally, my wheelchair with me. I could take it apart, and get it into the back seat of the Rans. That worked, but I couldn’t take anyone with me.
Cue the Bearhawk. I looked into them and fell in love with the big cargo doors, and large cargo area. Plenty of room for my folded up wheelchair. In addition to my wheelchair, I use a converted Segway when I go to car shows, or air shows. I have a crane in the back of my truck to lift it in and out. I thought about Oshkosh, and the miles of cool stuff to see, and a lot of grass. Pushing a manual wheelchair on grass or sand really sucks. So I put in mounts in the cargo section that will hold a very similar crane that’s in my truck. The plan is to remove the back seat, and load the Segway. I haven’t gotten the geometry on the crane right yet, so I haven’t tried it. But either way, being able to load my wheelchair, climb into the right seat, slide over to the “captain’s chair” in the left side and off we go.
I bought a very partially built fuselage, that I ended up re-doing most of what was done because of my engine/mission plans. QB wings were a must for me, after slow building the RV. First few years were slow, because my hangar was still being built, so I just had a small space in the corner of a friend’s hangar. Wings stayed in the shipping cart, and the fuselage was attached on top of that, so I did what I could. Last two years with my hangar complete (which is also where I live, in a small apartment inside) lots of progress was made and the plane eventually completed in October.
Engine is a Bob angle valve 360, with EFII fuel injection and electronic ignition. Good write up in a earlier Beartracks on the EFII system, so I won’t repeat what Ed Meyer wrote about his Patrol. I’m with him on this, as I think it’s a pretty good system. I didn’t put in the redundant systems like he did, except for two batteries, two fuel pumps with auto switch, and back up batteries for the panel. I went with a 6 gallon header tank in the cargo area with an optical fuel sensor that tells me the wing tanks are empty, or not feeding the header tank. Either way, time to land.
Prop is a two blade Hartzell Trailblazer.
Avionics include a Dynon HDX for each side, dual Dynon Com radios and associated switches and knobs. Dynon two axis autopilot, and the jury is still out on that. Like Jared has discussed, a 3 axis autopilot would be way better than my roll servo which I have set up on the aileron cable.
I covered the plane with silver Oratex, with vinyl graphics. Weight came in at 1375, but my interior, other than the leather seats, is pretty spartan. I feel like this plane is my aerial truck. Although I do plan on adding the wheel pants as soon as I figure out how. I think with the smaller tires, wheel pants just improve the look and maybe a knot or two faster. I bought Jared’s 26 inch Goodyears, but I don’t think I could climb in with those on, so they are also for sale!
First flight went pretty well, I brought along a CFI friend of mine to help me watch stuff and I was glad to have him aboard. Had a few squawks, mainly cooling, which was solved by increasing the exit area, adding a lip, and adjusting the baffles a little. The main improvement was to the air intake. The Bob motor supplied had a rear facing intake, so I used a large NACA duct with a 3 inch hose going right into the intake. Before I changed that, I used the air from the NACA duct sort of aimed at the air filter on the intake. But that caused the air to back up into the cowl and prevented the optimal cooling. Also, it was feeding the motor hot-ish air, which also isn’t ideal. Now the air goes right into the intake, the cooling issues are gone, and cooler air into the filter/intake.
I put a camera in the nose, under the prop, and that displays right on the HDX for taxi. My airport has lots of rolling hills and people park their vehicles all over, so the camera just gives me peace of mind while taxiing around. I’ve seen too many chopped up planes that were hiding under the nose, the camera was $20 and the video adapter from Dynon was under $200. I am really happy I put that it. I put LED landing lights in each wing, with steady or wig wag available. I put the combo position lights/strobe lights on each wingtip. Another useful mod I made was a hinged instrument panel. That’s already been helpful when I added the camera, video adapter and the O2 sensor display.
I’ve got about 20 hours on her so far, and every flight I fall more in love. Performance is solid, and it looks like a 75% cruise will be around 130mph true, at least above 3000 or 4000 feet. Don’t quote me on that just yet, I’m still working it out.
Keep working out there. There is no better feeling with your clothes on than flying a plane you built yourself, and the second build was no different!
