Fuel System Updates, Lowering AN804 Tee

Source: 2007 Q4 Beartracks, Bob Barrows
The fuel line layout needs to be as redrawn. It is important that the AN804-6D Tee is as close to the Fuselage bottom as space will allow. The fuel system in the Bearhawk is simple and a proven layout. I would NOT recommend any basic deviation from this design. Those builders using the extra range tanks as described in the October 1996 Beartracks should contact me (by mail) with the hook-up that they plan to use.
All tubing used in the fuel system is 5052 aluminum 3/8” OD. All hose is -6 size and all pipe threads are 1/4” NPT or larger. NEVER use teflon tape to seal fittings in an aircraft fuel system.
The four-way fuel valve needs to be ported with 1/4” – 5/16” passageways to insure adequate flow to the engine.
As shown in the sketches and photos, the fuel valve and gascolator are mounted on the floor near the flap control handle. This location allows the gascolator to be at the lowest point in the system as required to remove any water that may contaminate the fuel. The fuel lines upstream of the gascolator should not have any sags that could collect water and freeze while the aircraft is sitting. If you consider another fuel system – consider the above points. I do not like the inline filter for aircraft – use a gascolator.
-Bob
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Brake Line Fittings- Nylaflow and Brass

Source: 2007 Q4 Beartracks
Tips from EAA Chapter 105 – Benton Holzwarth Brake Line Fittings by Randall Henderson
When I was putting my RV-6 together, I was a bit skeptical of those plastic fittings that are used on the brake reservoir and master cylinders. A couple of years later my concern was justified when the tee fitting, way up high on the back side of the firewall, began leaking messy brake fluid all over my firewall blanket. I tried in vain to tighten the fitting but eventually gave up, and many curses and contortions and sore muscles later, had the tee fitting and also the elbow fittings at the master cylinders replaced with brass versions.
I know I’m not alone on this, because at the last meeting, I mentioned this to our host who I’d noticed was installing the standard plastic fittings just like I had, and several others chimed in in agreement. So my ‘tip’ for people building their planes is to chuck those plastic fittings and instead use brass versions.
The specific part numbers for the brass fittings, 1/4″ size, are: 271P-04×02 (male run tee) 269P-04×02 (male elbow) I couldn’t find the 272P in the current Aircraft Spruce catalog, though they may have them if you ask. Wicks’ catalog lists both. Note that the application may be different depending on whether you have nylaflow or polyflo tubing, so pay attention to the directions and if in doubt, talk to the manufacturer or an EAA technical counselor.
Editors note: Some applications also require that a ‘tube insert’ (pn. 2030-4) be inside the tubing to keep it from leaking.
Note from Bob Barrows: I prefer aluminum aircraft type fittings and aluminum line rather than brass or plastic fittings.
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Makin’ Beartracks- Bodie

Source: 2007 Q4 Beartracks, Pat & Carol Fagan
Bodie“Goodbye God, I’m going to Bodie.” Those chilling words were penned by 11 year old Anna Lockmoor in 1879 when her family moved there in search of their fortune. Bodie was known as the wildest mining camp in the west and once sported a population of 10,000. It was said there was an average of one murder per day.
Today, the remaining town is a State Park and is in remarkably good shape. The state maintains it in a state of “arrested decay”, which means they will repair roofs and foundations but otherwise the buildings are left alone. What is truly fascinating about the town is that when the residents abandoned the town, they mostly left all their belongings behind. Even more remarkable is that over the years antique hunters and vandals left the town alone. Walking the streets, looking inside the windows of the shops, you get the eerie feeling that the inhabitants must have been spirited away by aliens.
Having long been fascinated with the town, I once searched for a landing spot near by. I don’t know how I missed them, but it wasn’t until much later while looking at a sectional I noticed two dry lakes north of town. This past summer Carol and I flew over the dry lakes on our way to Arlington and, from altitude, they looked land able. Although excited to make the trip I chose to wait until the weather cooled off some and wouldn’t you know, by the time the planned departure date came we were not so much concerned with heat as much as snow. An early fall snow storm threatened to cancel the trip for the year but it turned out not to be a factor.
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The westernmost dry lake is more than twice the size of the eastern one. I intended to land on the larger one but noticed on close inspection that there are a lot of large rocks scattered about. In addition, the surface looked pock marked with divots of an indeterminate depth. We flew over to investigate the eastern dry lake and found it to be in much better shape. Both lakes sit in somewhat of a bowl formed by a lava dike. Wanting to test the surface prior to landing, I set up for a touch and go, but the combination of dropping into the lake over the dike, coupled with the high ground speed due to the high 8500’ field elevation caused me to rethink the wisdom of landing on the smaller lake bed. We diverted back to the large lake bed and I found a line that would allow me to miss the larger rocks. I made a trial pass, bouncing the wheels on the surface and found it to be hard and relatively smooth. One more time around and we were down and taxing to the southern edge of the lake bed. While tying down the plane I discovered I had landed down wind, so the eastern lake bed would have been sufficiently long.
The town is a 4 to 4.5 mile hike south, on the other side of the hill. There is a 500’ to 1,000’ elevation gain and loss each direction. The variation depends on whether you choose to contour around the hill or climb all the way to the hilltop. That may not sound like much, but coupled with the high elevation, the trip can be strenuous. It is also possible to mountain bike to town as there is a decent road that winds along Bodie Creek to the east. It is about 7.5 miles to town by bicycle, but the elevation change is only 400’. Unfortunately, there is no camping in town, so you will have to hike back to the plane to overnight. To get the most from your walking tour walk south through town to the entrance station.
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Although you could avoid paying the entrance fee, the detailed walking guide you get when you pay is well worth the few dollars. We only had time to glance in a few buildings, yet we saw some incredible sights. The undertaker’s office had several coffins inside. A casino had an old slot machine, roulette tables with chips scattered around, and a bar still stocked with bottles. A mercantile looked as if you could walk right in and purchase all the supplies you needed, provided you didn’t mind the dust. Spend some time in Bodie and you’ll come away charmed.

Demo flights at EAA Chapter 889

Source: 2007 Q3 Beartracks, Cathy White
Mark and I flew from Lakeway to the local EAA chapter #889 – Highland Lakes Chapter meeting at Williams airport. A beautiful 2600′ grass strip located just south of Buchanan Dam. We arrived before the crowd so I was able to take up the chef, our host and Chapter President Dick Gauldin, a retired Austin Police Lieutenant. We taxied to the end of the runway and launched to the south. Climbing out at 60 MPH initially. Then clean up the flaps and head out for a little demo of the airplane’s best traits.
07q3cateFirst off some slow flight. Then into a departure stall, holding the stick full aft for a falling leaf. The airplane is so docile it does a little bobble of the nose as it recovers and then re-enters the stall. Gentle as you please. Some pedal turns at 40 MPH indicated, then with some power applied we hold altitude as the airspeed needle hits the peg at the zero point. We came in for a nice landing and by that time others were showing up and our chef had to get to the task of grilling fajitas.
We were joined now by about 20 fellow EAA’ers for this gathering. One of which is the proud owner of an AirCam. We were treated to great company and even better vittles. After the meeting/lunch break, I took Roy Immel (81 years young) for a Bearhawk ride. He is a long time aviator who flew more missions in WWII than I have dreamed about. He started in J3’s, then Stearmans, then T6’s, then P40’s in WWII. He retired from the military after WWII, but was recalled for Korea flying C-45, C- 46, and C- 47. In Vietnam he flew C-124’s & B-47’s. He’s been actively flying ever since and it shows. It was a great treat for me to give him the controls so I could watch his handiwork. Roy’s comments about the Bearhawk: “I really enjoyed that machine. It was a lot of fun to fly. Easy to handle. What a takeoff!” Roy’s current machine is a C150/150 taildragger.
Sometimes you get lucky and are in the presence of a pilot who can make an airplane sing. Roy Immel is such a man. It reminded me of when I was a child watching my Grandpa ride horses. The horse never had a doubt who was in charge, and that day neither did the Bearhawk. Roy brought the Bearhawk in for a great three point landing. Nice job Sir.
Remember that AirCam I mentioned earlier – it belongs to a chapter member. I was fortunate to reap some more benefits of the Bearhawk world and all it exposes me to, by getting a ride in the AirCam. What a performer. I had never been in anything like it. What a view indeed. Thanks for the unexpected treat. Next Mark and I departed across North Austin, just east of Georgetown to Cross Country Airpark. Another beautiful grass strip that made me crave such a living arrangement for myself as soon as I can muster it. We were delivering an engine mount to a gentleman who is currently building a Bearhawk. Although Rick Smith had already purchased his kit and is already well on his way in his kit construction, he had not gotten a ride in one yet. Today we would change that.
As we taxied out and lined up, I mentioned what the flight would consist of. We took off and at about 1000 AGL, Rick said to me “I guess the demo is over”, meaning of course that once you experience the takeoff you’re sold. I
smiled and gave him the plane. We did a similar demo as the earlier flight that day. Rick brought us in for
a three point. He had a nice grin showing. I wonder how late he stayed up that night tinkering with his Bearhawk.
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Makin’ Beartracks- 2 Degrees

Source: 2007 Q2 Beartracks, Pat & Carol Fagan
The world of aviation is an incredibly small universe. The normal 6 degrees of separation is often as little as 1 or 2 degrees. It is a world of beauty and sadly, tragedy. On our trip to Oshkosh this year, Carol and I received a refresher course in these facts.
We were fortunate to find ourselves with 3 weeks of vacation this summer that happened to coincide with the EAA shows at Arlington and Oshkosh. Planning to fly across the top of the states from one show to the other, we were presented with the opportunity to spend the night in North Dakota. You would be right to ask, “Why the heck would we want to do that?” We once purchased one of those state maps you see on motor homes with the multi colored states to show where you have been. Our rule was drive-bys weren’t allowed. We couldn’t apply a sticker unless we spent the night in the state. Not surprisingly, we never managed to fill North Dakota since it isn’t on the normal tourist route, and let’s face it, there isn’t much to see.
I mentioned our plans to Budd Davisson and he told us about a guy somewhere in North Dakota who scratch builds full sized P51 Mustangs from the original drawings. Budd wasn’t sure where the guy was located, but offered to look it up if we were interested. I didn’t think we would have the time, so I told Budd not to bother.
07q3fagan1We had been doing some low level recon on the west side of the North Dakota (which will be covered in a future article) and were getting beat up pretty good with the wind and thermals. Carol and made a pact that we would depart Mott, where we had stopped for fuel, and climb to 9500’. If the air wasn’t smooth there, we would land at Ashley for the night. The air was smooth, with a nice tailwind, so now we had to determine how far we could go and still remain in the state overnight. We set our sights on Wahpeton, on the Minnesota border.
The next morning we headed back to the airport, happy that we had finally knocked of North Dakota. While I was preflighting the plane, a fellow walked over to see what we were flying. We chatted for a while and with a jerk of his thumb, he indicated that he worked in the hanger behind him. The hanger doors were open and peeking out was a lime green wing leading edge attached to some kind of warbird. I didn’t recognize it because of a scoop above the propeller. I asked if it was an Aircobra. He replied, “No, it’s a P51 A model. We build them.” We had just happened to blunder into the very same shop, Tri-State Aviation, that Budd had told us about. This particular Mustang had been built from scratch and was used in the filming of the new movie “Thunder Over Reno”. It was painted to mimic the famous race Mustang “Precious Metal”. Hanger mates included a B25, a TBM, and all manner of other projects. He showed us through the rest of the shop where they were just getting started on building a “D” model fuselage. I looked at the drawing he was working from and couldn’t make heads or tails of it. I would have had to blow the thing up 10X to figure anything out, but he was perfectly happy with it. The next hanger over had 4 “D” models in various stages of finish, including one they were getting ready to fly to Oshkosh.
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We thanked him for our tour and went on our way, marveling at the coincidence. We arrived at Oshkosh on Sunday. Tuesday, while walking back to our tent, I was surprised to see the lime green wings of “Precious Metal” parked in Aeroshell Square. I told Carol about it and we speculated about what misfortune must have befallen the aircraft they had planned to bring. On Friday, the owner of Tri-State Aviation, Gerald Beck, was killed and “Precious Metal” was destroyed when the plane collided with another Mustang after a routine air show performance. Per his wishes, Mr. Beck was buried in a modified propeller crate. For us, the tragedy closed a circle in our incredibly small world of aviation.