The BF9-2 is a biplane of my own design. I drew up preliminary drawings in 1993, and began construction in October of 1995. At this time the airframe structures are nearly complete with the exception of the upper wing, which is under construction now. The aircraft is about 5% larger than a Pitts S-2B in linear dimensions. However it is heavier, mostly due to the use of the Russian M-14P radial engine and a 3-blade Whirlwind propeller. The airframe is stronger to support the heavier engine/prop combination, and this puts the calculated empty weight at just under 1400 lbs. At airshow takeoff weight the power loading will be 4.88 lbs/hp, making it very high performance indeed. The propeller will be 102" in diameter, and will clear the ground by only 13" in the three-point attitude. All takeoffs and landings will be in the 3-point attitude, as raising the tail to level flight would leave only 4-1/2" of ground clearance. The fuselage is somewhat smaller internally than the Pitts Model 12, and there is less clearance between the engine and the firewall. Therefore the engine oil tank had to be mounted outside of the fuselage structure, but under the outer aluminum skin. It is mounted on the left side of the fuselage, just behind the firewall and holds 4 gallons. The biggest challenge so far on the upper wing was the center section splice, which is a carbon copy of a Pitts wing. The rear splice blocks, which taper outward and back from the centerline, were marked at the proper angle of 6 degrees 38 minutes, and sawed on a vertical bandsaw close to the line, then sanded on a belt sander to the line. After gluing the splice block to the left and right spars, the now 22' long spars were layed face up in a routing box, and the face routed flat. The front splice block was glued on. At this time all the ribs are on, but not glued. The center section plywood is on the under side, and the 1/8" plywood reinforcements are on at the I-strut attach points. Wire pull blocks are ready to install, and all steel bushings have been made and cad plated, ready to install. I expect the upper wing to be nearly complete, at least structurally, by the end of October. No, I don't have an estimated date of completion. It will be done when it is done, and that's all I know.

June 2001 update
As of June 2001 I just about have the structural airframe complete. I'm just finishing up the I-struts, which are built entirely of round tubing. With the price of streamline tubing so high now, I redesigned them to give a streamlined profile without the high cost streamlined tube. The top and bottom pieces are square tube, ala Pitts Special. The main upright tube is 1-1/2" round x .083" wall, which gives the equivalent strength of the streamlined tube that would have been used. The fore and aft diagonals are made of smaller diameter tube, and the trailing edge will be faired with a taper wood strip, and then the entire strut covered with fabric. The struts weigh 13.375 lbs each, and cost 31% of the cost of using streamlined tube.

The lower wings need only the wood leading edges and some other small areas covered with plywood, and trailing edges installed and they will be ready for cover. The upper wings need plumbing for the pitot system, center section fittings installed, center section plywood covering, leading edge plywood, tips shaped, and trailing edges installed. Ailerons for the lower wings need leading edge blocks and plywood skins and trailing edges. The upper ailerons have yet to be built. All the hinge brackets for the ailerons were machined from billet aluminum. Part of my goals in building this plane was to try new ideas (to me, anyway), and learning to use a mill was one of them. It took 24 hours to machine the required 8 fittings.

Something I learned, much to my chagrin, when I installed the top wing for the first time, was that the airplane will be too tall to get in and out of the hangar without modifying the door height stops. This plane is tall! The leading edge of the top wing is about 95" off the floor of the hangar. I'll be using a 3-blade prop 102" in diameter, so I won't be able to lay the prop horizontal to clear the door.

Specs that I am reasonably sure of are as follows:
Wingspan..........21 ft.
Chord................48 in
Wing area.........158 s.f.
Wing loading....12.0 lbs/
Length...............18 ft 9-3/4 in.
Empty Wt...........1400 lbs.
Airshow Wt........1898 lbs.
Seats...................2 in tandem (front seat no Controls)
Engine................Vedenyev M14-P, 360 HP supercharged 9-cyl. Radial 
Propeller.............Whirlwind 3-blade composite, constant speed
Roll rate..............300 + degrees/second
Rate of climb.......4,000 + FPM
Cruise speed........175 mph
Range @ 65%.....525 miles, 30 minute reserve
Fuel capacity.......55 gallons internal tank
Color....................I don't know. It isn't painted yet.
Completion date..I don't know. It isn't finished yet.
Value...................I don't know. I would have to sell it to find out.

PROGRESS REPORT BF9-2 MARCH 30, 2003
August 1, 2001, Bob Barney bought a new hangar on the east side of Skypark, and we moved everything there and set up shop over the next six mnths. This put a stop on all airplane progress for both of us. Near the end of January 2002 we got back into the swing of things, and the extra shop space proved worth the loss of time for the move.I have had all welded parts powder coated. I found a company about a mile from Skypark who could do the sandblasting and coating all in-house. The price was excellent, and saved me the hassle of trying to find a location and equipment to do it myself. Not to mention that powder coating is a tough finish!
I ordered the aluminum sheet metal from a company in California, who said it could all be rolled for shipping by UPS, saving me the expense of trucking. What they didn't tell me was that they would roll it into a 12 inch diameter circle. When I received the metal the container was in perfect condition, but all the metal had been oil-canned in over 50 places from the hands of the people doing the rolling. I got a 20% refund, which amounted to paying 80% for damaged goods. I went ahead and used the metal to determine  panel shapes and hole locations, and how I actually wanted to do the work, but it all needs to be done in good metal. I have bought the replacement aluminum from a local supplier, and will be starting on the finish metal work soon. If you look close in the pictures you can see that it is not acceptable metal work.........yet.  I had the turtledeck made out of aluminum, but wasn't satisfied with the 
shape, nor the durability of the finished product. I redesigned it out of wood, and am much more pleased with it. It will cost me a small weight penalty, something I never thought I would give in to, but I think in this case it will be worth it. It will be skinned with 3/32" birch plywood.The instrument panel in the pictures has some instruments there just to fill the holes. I haven't aquired all the "real" ones yet. I made a second panel blank because I know from experience that I'll be changing the panel in the future. Inexpensive instruments now, the ones I really want later. You'll notice the space in the center of the panel. This is where the aerobatic card resides during those kinds of flights. On cross-country flights a hand-held GPS will use the space. With the panel so small there 
wasn't room to put the g-meter. It is mounted in the center of the radio box down low in the cockpit. I never use it during aerobatic flight anyway. It is just a "bragging" instrument for the most part. I will have an HCI non-recording g-meter on the panel. It is 7/8" wide by 4" high, and fastens on with sticky-back tape. That will be plenty sufficient for in-flight information.Once the sheet metal work is done I'll install the fuel and oil tanks, do the plumbing and wiring, and permanently mount the wood stringers, which are laminated out of three pieces of 1/2" by 5/16" spruce. The airplane will be 
fully rigged, with all controls installed, before any covering takes place. The wings still need the plywood leading edges, and ailerons need to be built for the upper wing.I don't believe in deadlines (anymore). I've seen so many of them go by. But, where I have only been able to see the tunnel at the end of the tunnel, 
I can now see a very faint light out there somewhere. If one doesn't give up, it will be done some day. I currently have about 2300 hours into the project. I figured 2500 to finish, and I'll obviously be over that. But I see so many kit-planes in Sport Aviation that the builders claim to have spent much more time than I have, so I feel like I've done very well as far as hours/progress goes. And when I'm done, I'll have exactly what I want (except for the things I would change if I did it again, of course).

Danny's e-mail allynhsorensen@hotmail.com

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More Photos since the engine was first started On August 1 2008

Bob Barney's RB-4 & Danny Sorensen's BF9-2