Friday, May 23, 2014
Piper L-18 Super Cub
The Piper PA-18 Super Cub is a two-seat, single-engine monoplane. Introduced in 1949 by Piper Aircraft, it was developed from the Piper PA-11, and traces its lineage back through the J-3 to the Taylor E-2 Cub of the 1930s. In close to 40 years of production, over 9,000 were built. Super Cubs are commonly found in roles such as bush flying, banner and glider towing.
While based on the design of the earlier Cubs, the addition of an electrical system, flaps (3 notches), and a vastly more powerful engine (150 hp), make it a very different flying experience. Although the "standard" Super Cub was fitted with a 150 horsepower (112 kW) Lycoming engine, it is not uncommon to see them equipped with a 160 horsepower O-320-B2B, or even 180 horsepower (134 kW) Lycoming O-360 powerplant. The high-lift wing and powerful engine made the Super Cub a prime candidate for conversion to either floatplane or skiplane. In addition, the PA-18A (an agricultural version) was produced for applying either dry chemical or liquid spray.
The Super Cub retained the basic "rag and tube" (fabric stretched over a steel tube frame) structure of the earlier J-3 Cub.
The O-290 Lycoming powered Cubs (135 hp) followed and would take off in about 200 feet (61 m). The landing distance remained the same at about 400 feet (120 m), or 300 feet (91 m) using flaps. With the use of the Lycoming O-320 at 150–160 hp, the Cub's allowable gross weight increased to 1,750 lb while retaining the capability of a mere 200 feet (61 m) required for takeoff.
The PA-18 has developed a very dedicated following in the bush-flying community, and many modifications have been developed for it, to the point where it is quite rare to find an original, completely stock Super Cub. Modifications include extended baggage compartments (reaching farther back into the fuselage, or even two-level baggage compartments in the top and bottom of the rear fuselage), external luggage pods, fuel pods, lumber racks for carrying construction materials into unimproved bush runways. Also the removal of header tanks, larger 24 or even 30 gallon wing fuel tanks, extended main landing gear for better ground clearance of the propeller, strengthened tailwheel springs, the addition of a small third passenger seat in the luggage area and lightweight generators and starters. Also various different mount areas for the battery (to move the weight forward, and reduce tail weight to shorten takeoff distance), various different tailfin shapes to increase surface area, lengthened flaps, various wingtip designs, vortex generators on the leading edge of the wings, movement of the electrical panel from the right wing root to the dashboard to reduce fire hazard during a crash, and even the addition of a constant-speed propeller. Above all, the most common modification is the addition of "bush wheels", large, soft, low pressure balloon-tires designed to absorb impacts from rocks and boulders, and to not sink into sand or other soft surfaces, ideal for off-runway landings.