The PA-18 Super Cub was a strengthened PA-11, itself a modification of the original J-3 Cub. With only a few minor changes and a 150-horsepower engine, the PA-18 still looked like a Cub, although it came in several paint schemes and lacked the familiar bear logo on its tail. About 8,500 Super Cubs were built at Lock Haven, Pennsylvania, and they proved popular as private and utility aircraft and as military trainers.
The Atomic Energy Commission (AEC) used this Super Cub in its uranium exploration program in the West during the 1950s. The rough and sometimes inaccessible terrain made an airborne survey a logical choice, and the AEC's fleet of 10 low, slow, and inexpensive Super Cubs maintained an enviable record of safety and reliability. A scintillation counter used to detect gamma radiation is in the rear of the airplane.
The Atomic Energy Commission (A.E.C.) operated PA-18 Super Cub N1872P in its uranium exploration program carried out in the western United States during the 1950s. As part of the fleet of 10 airplanes, it made radiometric surveys, including Isorad mapping, of the terrain for use in the ground-based laboratories and evaluation centers. The bulk of this program was carried on for about three years during the mid-1950s in the quest for additional sources of uranium rich deposits for the expanding nuclear industry in the military and civilian markets.
The PA-18 Super Cub series airplane was the last Piper production airplane type to carry the Cub nameplate. The first upgraded version of the J-3 was the PA-11 Cub Special which was distinguishable by the closed engine cowling over its 65 hp Continental engine. Soon a Continental C-90 AF engine was added. More important, the PA-11 was the first Cub that could be flown solo from the front seat. The front seat was higher and more forward because of the movement of fuel tanks from the nose to the left wing root section of the aircraft and the resulting change in the center of gravity. The PA-11 was first flown in August 1946 and a total of 1,428 were built between 1947 and 1950.
The PA-18 Super Cub was a strengthened PA-11 with the ability to support up to a 150 hp engine. Externally the only noticeable structural change was a slight additional rounding of the vertical fin and rudder. The PA-18 was introduced in November 1949 in three basic versions: the Standard, the Deluxe with starter and generator, and the Agricultural version. The famous bear cub logo was replaced by a circular medallion in which the name Piper was crossed vertically and horizontally using the middle "P" as the common letter for both positions. The standard Cub Yellow paint scheme was replaced annually with changes of colors and trims. The PA-18 was produced at the Lock Haven factory until that plant was closed in 1983, but production resumed in 1988 at the new Piper facility in Vero Beach, Florida, under new ownership. About 8,500 civilian Super Cubs were delivered and more than 1,800 airplanes were also delivered to the U.S. and several foreign military services as L-18Cs and L-21s for liaison, training, transport and target tugs work.
The A.E.C. was the sole owner of the N1872P during its operational life. This airplane, powered by a 150 hp Lycoming engine, was delivered to Boyd Aero Service, the Piper distributor in Santa Fe, New Mexico, and it became the property of the A.E.C. on January 26, 1955. The decision to perform these surveys from the air was made on the basis of a comparison of the costs to operate an airborne system to the costs of doing it by conventional geological methods or by the use of ground based vehicles. The rough and sometimes inaccessible terrain to be surveyed made the airborne approach a logical choice based on accessibility, cost and time. The low and slow Super Cub, priced at only $6,000, proved to be superior to the only emerging helicopter which had yet to establish a consistent record of reliability and was expensive.
The multi-year program flew the aircraft a total of 14,000 hours at an average operational cost of about $40 per hour, or $1.00 per mile. The pilot was required to have a commercial pilot rating with at least 500 hours of flight time and was also required to be a licensed airplane & powerplant mechanic (A&P) so that he could maintain the aircraft in the field. The section chief, who was also the airborne geologist/observer, was required to have sufficient pilot training to be able to handle the airplane in the event of an emergency. The geological instrumentation in the aircraft consisted principally of scintillation measurement equipment, special recording equipment and cameras to record the scintillation profiles, and maps for ground laboratory use. Survey altitudes usually ranged from 25 to 100 feet and required excellent low speed maneuverability near cliff sides and box canyons. The Super Cub boasted an extraordinary safety record in this rugged terrain with only two accidents, neither one with serious injury, occurring during the entire program.
By February 16, 1961, N1872P had 1,487 hours of flight time. The Smithsonian acquired the Super Cub and its detection instruments as a government transfer from the Grand Junction Colorado Operations Office of the US Atomic Energy Commission to the Arts and Manufactures Department on April 18, 1963. It was transferred to and accessioned by the National Air and Space Museum in 1976. The airplane is currently on display at the Museum's Stephen F. Udvar-Hazy Center at Washington Dulles International Airport in Chantilly, Virginia.