As we progress well into the second century of flight, most of us take to the sky in machines of metal or advanced composites like carbon fiber and Kevlar. The science is solid and techniques well established for flying machines of these materials. But if you step away from the mainstream types most commonly decorating the ramp at your local airfield, you may well stumble across wooden airplanes that survive as antiques, warbirds and homebuilt designs, as well as a few types built more recently. There are even a few designs in current production—one featured below is a throwback to the days of old, while another is a Light Sport Aircraft utilizing a wood wing to stay below the 1,320-pound gross weight limit.
At the outset of aviation, wood was a logical material for aircraft construction. Lightweight alloys were still anything but common, but wood was widely available and used for everything from bridge timbers and railway coaches to furniture and buildings. Technically, some metal structures did take flight as rigid airship frames before the Wright brothers even started building gliders. But for the first several generations of aircraft, wood was a critical design component. From the early pioneers through the Golden Age air racers, wood allowed for strong structures with a smooth finish that didn’t require rivets disrupting the airflow. It could be used in a number of methods. The earliest flying machines were often a skeleton of wooden frames, with a fabric skin stretched over it. As machines gained speed and a need for strength, plywood skins formed over ribs, stringers and bulkheads made for a strong structure without a lot of weight. Even as aluminum became a popular building material for aircraft, wooden spars, such as on Piper Cubs until early 1946, persisted as a light and affordable component. Many of the lighter Cubs sport spars of spruce or fir. Wood spars continued in new-production Champs, Citabrias and Decathlons until the 1990s.
Even today, wood persists in plenty of homebuilt designs and even a few certified aircraft in current production. Wood is light, strong and, unlike metal, it doesn’t have a “memory.” It either breaks, or it doesn’t. Metal, on the other hand, can be observed failing as you bend a paperclip back and forth several times. With each bend, it deforms more easily, and when it finally does break, it does so with less force than originally needed to bend it. Wood is far from a perfect material, though. Termites aren’t so much a threat as rot—moisture is the enemy. Having a mechanic who is knowledgeable and comfortable with wood structures is key. Let’s take a quick look at 10 types, some old and some new, to see what a broad variety of wooden wonders might decorate an eclectic aviator’s logbook.
4. Pitts Special
When Curtis Pitts’ scrappy biplane took to the air in 1945, it was a vastly different machine from the aerobatic competitors and airshow performers of today. With two ailerons fitted to flat-bottom wings and a C-85 on the nose, it flew well, but in a familiar pattern of bigger-faster-more powerful, the Pitts grew over the years. In 1962, Pitts offered S-1C plans for those who wanted a Pitts Special of their very own, and that design is still popular—if not especially competitive—today. Welded steel structures make up the fuselage and tailfeathers, but the wings are a work of wooden art. With a mixture of stick-built ribs and plywood sheeting, the basic structure is stronger than the average aerobatic pilot could ever need. Various models of the Pitts have been stretched to two seats, fitted with four- and six-cylinder Lycoming engines, and the Pitts Model 12 packs a massive Russian Vedeneyev M-14 radial engine that produces 375 horsepower stock but has been tuned up past 450 horsepower by some operators.
Pitts’ ground handling is the stuff of Saturday-morning hangar flying gold at your local FBO, but most of the horror tales come from poorly built or repaired aircraft, or from pilots who have never actually flown the design. Pitts owners report the ground handling as plenty manageable. “It only does what you tell it to do,” is a common refrain. That said, there are plenty of instructors offering Pitts-specific instruction, and a couple grand spent with a CFI is a lot cheaper than a prop strike inspection and rebuilding a wingtip.
Plans for the S-1C and S-1S are still available through Steen Aero Lab, and flying copies are always for sale, ranging from sub-$20,000 to $40,000. The S-1T, a factory-built and certified bird, demands a premium, as do two-seat S-2 designs.
Height: 6 ft 3 in
Wing Span, Upper: 17 ft 4 in
Length: 15 ft 6 in
Empty Weight: 720 lb
Gross Weight: 1,150 lb
Vne: 176 kts
Stall Speed: 56 kts
Maximum Rate Of Climb At Sea Level: 2,677 ft/min
Service Ceiling: 22,300 ft
Range With Maximum Fuel, No Reserve: 315 mi
Photo by Huhu Uet via Wikimedia Commons