The Barr 6
by Howard Levy
Sixty-0ne-year-old Jim Barr, of Williamsport, Pennsylvania, reports that 15 years and $2 million have been personally spent in developing his now basically all composite, 6-place, high wing, kitted Barr 6 airplane. “I have been associated with aviation all of my life,” he related, “as my father was a FAA instructor and examiner of A&I mechanics.” Jim has logged 1800 hours as a Private Pilot, and through the years, airplane ownership has included 3 Beech Bonanzas, the first a 1955 F35model. This was followed by a couple of Beech Barons, then 2 Beech Dukes, a Helio Courier, and finally a Cessna 206. “In the mid-1980s, I found that a person could not really afford even a 2-3 year old Beech or Cessna, as their cost had sky rocketed,” Barr said. “The direct operating cost of my Duke had topped $450 per hour.”
Barr is an aeronautical engineer, but only worked
at that occupation for two years, before turning to automobile sales. But after
conducting a market survey, he believed that because of the cost of purchasing
and operating a conventional factory airplane, there was a place for a larger
kitted airplane. He also builtup a Kitfox to prove kit building capabilities,
as well as drew on his own flying experience with various type aircraft in
regards to incorporating the best of each in his project.
The 5th version appeared to be the answer. It eliminated the steel in the fuselage, and basically employed sandwiched components throughout, made up in pre-pregnated E-glass, with Nomex honeycomb cores, that were vacuum bagged and cured at 280 degrees. However, there were still some design flaws in regards to strength in load carrying areas, and after some further research, Barr utilized Charley Rodgers’ concept of applying graphite rods into the aircraft’s structure. Rodgers was a former Bell engineer dealing with composites used in helicopters. The Barr 6 now internally contains over 5000 feet of .097 diameter rods, cut up and put together in packs, to carry the loads. Barr stated that the skins only carry local loads and not that of the aircraft. Jim Barr also noted, “The steel structure in the fuselage resulted in the airplane having a 1400 pound useful load, whereas the composite/rod pack fuselage boosted the useful load to 2300 pounds.” The fuselage is fabricated around a composite sandwiched keel, and has E-glass/rod pack longerons at each of its four corners, plus 4 vertical E-glass panels that are likewise strengthened by rod packs. Two vertical E-glass rings with rod packs, carry the wings, landing gear, and struts. All of the skins are produced with pre-pregnated 7781 E-glass and a light weight epoxy resin content of 36-38%. “The fibers in the prepreg glass remain in a straight line, making for a stronger skin,” Barr commented, and added, “the honeycomb core is wrapped in adhesive.” Fuselage skin thickness range between 2 and 6 ply, and the honeycomb cores are 3/16 inch and 1/4 inch thickness.
Barr makes up the 4 x 10 foot sandwiched E-glass/Nomex/Epoxy panels from which all of the spars, ribs, longerons, vertical members, and the keel are cut. “We use bolted metal parts in the airplane rather than bonded,” Barr affirmed, “and the bolts are in a Zipper Effect, in which we employ at least 4 inline bolts, rather than a single larger bolt. If for any reason one bolt gives way, the remaining bolts retain the integrity of the system.
Barr brags of the airplane having a large comfortable cabin. Ground to sill is only 2 feet, the inside height is 49 inches, width across the pilot’s front seats 52 inches, center seats 52 1/2 inches, and rear seats 44 inches. A 38 inch wide, 190 pound capacity baggage area is located behind the rear seats, accessed from the cabin, as well as a left side door. Forward seats are accessed by a left side 40 inch x 37 inch door, and cabin passenger seats by right side double doors that measure 39 inches high and 45 inches wide. Instrument panel carries standard flight and engine instruments, plus a Cessna RT-385A Nav/Com, and RT-459A transponder/encoder. Hand-holds include an A23 Sport Com/Nav, and a Garmin 295 GPS. A TruTrak Flight Systems Digiflight 11Vs autopilot is to be added, as well as a PS Systems audio panel marker light 6-place intercom.
The tapered wing utilizes a NACA 2412 airfoil, to which Barr noted, “It has been proven that wings with this airfoil continue to fly, even with ice build-ups.” Spars are an I-beam type, the forward unit 7 inches high and slightly canted back at the bottom. It is located at 7 3/8 inch mean chord from the leading edge. Rear spar, vertically installed, is 32 inches aft of the front spar. Rear Spar webs and caps are cut from the composite panel, and 4 rod packs are positioned below the top cap and above the bottom cap, on each side of the web to carry the wing loads. Eight solid ribs, likewise cut from the panel, are fitted in each wing half. Wing panels are sealed with PR-1422 A-2 fuel sealant, making it possible to carry up to 75 gallons per side.
Ailerons are a Frieze type, with each having a 71 inch span, and 18 inch mean chord. They are fabricated in materials like the wing, and each has an I-beam spar 5 inches aft of the leading edge, and containing 4 solid ribs and 4 nose ribs. Flaps are a slotted type, although operating much like Fowlers. They have a 107 inch span, a 21 1/2 inch chord, and deflect 40 degrees. Construction is like the ailerons, with an I-beam spar 5 inches aft of the leading edge, but also an additional short spar at the outboard ends. Each flap is fitted with 9 ribs.
Tail surfaces are likewise of skinned, I-beam, and solid rib construction. Horizontal surfaces span 13 feet, with the elevator having a mean chord of 20 1/2 inches, and the stabilizer 25 1/4 inches. A 43 5/8 x 7 1/2 inch trim tab is installed on the right elevator half. Rudder is sweptback, is 5 feet high and slightly tapered, with a 24 inch mean chord. Fairings at the fuselage/stabilizer/fin area are said to be load carrying.
The airplane is fitted with a fixed trigear. The nosewheel is steerable 35 degrees right/left. It employs a tubular aluminum tube with hydraulic shock absorption, and is fitted with a Cleveland wheel and a 10 ply, 5.00x5 Goodyear tire. Maingear legs are 2-piece spring steel that bolt into a fuselage box. Wheels and brakes are also Clevelands, and the tires 6 ply Goodyear’s 6.00x6. Maingear track is 8 feet 5 inches, wheelbase 8 feet. An Edo 4930 float installation is also possible.
The subject prototype is now powered by a Lycoming IO-720-A1BD engine developing 400 hp at 2650 rpm, and swinging an 83 inch diameter, 3 bladed Hartzell constant speed propeller. Recommended engine TBO is 1800 hours. The engine cowling is said to be capable of handling 274 mph speeds. Flaps are fitted at the rear bottom of the cowling, and said to be large enough to handle seaplane applications.
Barr reports that he commenced the program in 1989, and then put 10 years into building tooling, 1 year constructing the airplane, followed by 3 years of rebuilding the airframe to incorporate various workable systems, as well as having a hangar/workshop erected. Another year went into flight testing engines and airplane. Jim Barr now considers that he has a satisfactory kitted airplane that meets his targeted criteria. All composite components are manufactured in-house, as is a machine shop to fabricate special parts.
Kit price is $89,900, and includes the skins, 9-4x10 foot 2 ply core sandwiched panels for cutouts of spar webs, wing ribs, keel structure, fuselage bulkheads, cabin floor, and vertical ring structure. One 4x10, 8 ply, coreless panel is used to cutout front and rear gear box and some ribs in the flaps and ailerons.
Also included are Plexiglas windshield/side windows of 3/16 and 1/4 inch thickness, cowling, rod packs, roll of E-glass, a 55 gallon drum of epoxy and hardener, along with a computer containing the construction manuals.A Quick Build kit is also available, but must include a Builder’s Assist program at an additional $69,000 cost, but with a promise of the airplane flying in a year’s time. It is estimated that a flying, fully equipped Barr 6 will run to about $215,000.
Barr 6 Specifications & Calculated Performance
Wingspan 29 ft 11 in
Wing chord - root/tip 64 in/42 in
Wing area 174 sq ft
Aspect ratio 7.63
Wing loading 25.9 lb/sq ft
Power loading 11.25 lb/hp
Overall length 29 ft 11 in
Height 7 ft 2 in
Tail span 13 ft
Empty weight (1 seat/land/VFR) 2197 lb
Empty weight (6 seats/IFR/autopilot/radar) 2501 lb
Gross weight 4500 lb
Engine- Lycoming IO-720-A1BD 400 hp
Propeller - Hartzell constant speed 83 in
Propeller ground clearance 9 3/4 in
Takeoff run 900 ft
Takeoff over 50 ft 1800 ft
Takeoff speed 65 mph
Rate of climb 900 fpm
Climb speed - 80% power 110 mph
Max dive speed 274 mph
Max speed 248 mph
Max sea level speed 237 mph
Cruise speed - sea level - 75% power 206 mph TAS
Cruise speed - 10,000 ft 225 mph TAS
Cruise speed -15,000 ft 204 mph TAS
Range - 90 gal standard fuel/22 gph/10,000 ft 900 mi TAS
Range - total 140 gal with optional fuel 1440 mi/6.4 hr @ 225 mph TAS/10,000 ft Downwind landing speed 120 mph
Base speed 100 mph
Final speed 85 mph
Touchdown speed 45 mph
Stall speed - 40 degree flaps 62 mph at gross weight
Landing roll 750 ft
Landing over 50 ft 1400 ft
After Bill McCleary flew the Barr 6 for our aerial photography we asked if he would provide his thoughts about the airplane and its flying characteristics. Fifty-two-year-old McCreary of Motoursville, Pennsylvania is an ATP rated, 15,000 hour pilot who flies a Beech King Air 200 for a corporation, and during his “spare time” conducts aerobatic training in a Pitts biplane and an Acrosport. This is what he said about the Barr 6. “At first sight is looks much like other cabin aircraft on the flightline, but in particular the Cessna 207, as it as the same aerodynamic shape, although it is not of metal construction like the Cessna. However, it is of healthy construction and you can pound on it without any ill effects. It does sit low on the ground but I soon found that the low gear arrangement provides nice ground handling.
“Climbing into the pilot’s and co-pilot’s seats is usually through the large double cabin doors on the right side, but should passengers be already in the club seating cabin area we then use the left side pilots’ door. Hand, foot, trim, and other control arrangement are common to the 200 series of Cessnas. Instruments are based on 1980 aircraft systems, although a Garmin GPS is carried.
“The IO-720 engine, with a Slick SS 1002 starter system, comes to life on first turn of the prop, and it sits and idles at 600 rpm smooth as silk. The airplane taxies like a heavy 200 series Cessna, with the nose nicely steered by rudder pedals, and Cleveland brakes providing even, effortless stops.
“For takeoff , full power is applied, then you control the prop torque. Elevator control comes in at 30 mph, you lift the nosewheel and the airplane flies off at 65 mph at a 4150 pound weight. Best initial climbrate is 85 mph at full power and it is easy to keep the ball centered employing elevator and rudder trims. Cruise climb is 120 mph with power set at 85% and cowl flaps closed. Above 5000 feet the ram air intake is opened and filtered air is shut down. Power settings of 45, 65, and 75% provides a speed range of 150 to 210 mph.
“For let down the manifold pressure is set for a 500 foot rate of descent. In smooth air you can hold the airspeed up to 240 mph, but in rough air a 171 maneuvering speed is recommended. I enter the downwind with manifold pressure at the 15 to18 inch range, then level off with a speed of 160 mph. Upon dropping 10 degrees of flaps, I stabilize and trim the plane for a speed of 120 mph. On base, flaps are deployed to 20 degrees and speed is dropped to100 mph, and on final, flaps are lowered to the max 40 degrees and speed stabilized at 70 mph. I come over the fence at 60 mph, with control pressure trimmed off, and then touchdown on the mains at 40 mph, lower the nose, add brakes, and raise flaps. Rollout distance is 400 feet with slight braking at the 4150 pound weight. Because of pitch control and the low drag airframe, the airplane must be stabilized on final for speed and descent or it will float on touchdown. I also found that only moderate control pressures are required at indicated speeds below 140 mph, and light pressures at speeds of 200 mph. The airplane likewise flies like a composite glider in rough air. It takes turbulence with a whompf-whompf ride and not sharp jolts to seat or hand controls.
“The Barr 6 is not like a Beech Bonanza or Piper Lance, but rather a big utility airplane with a 4500 pound gross weight and large cabin. It is like flying a Cessna 210 with 400 hp, and has an excessive amount of power on takeoff , climb and cruise flight ranges. A Cessna 172 or Skylane is a much easier type to fly for quick trips and no requirement of a large cabin useful load or higher speed. The Barr 6 certainly stands by itself.”
Copyright © 2006 Steve Morrison