The Langley 2-4, variously described as the Langley Monoplane or Langley Twin was a twin-engine utility aircraft built in the United States and first flown in 1940. Named in honour of Samuel Pierpont Langley, the aircraft was designed by Arthur Draper and Martin Jensen to make use of non-strategic materials in its construction and thereby avoid any shortages brought about by war. Its design was conventional – a low-wing cantilever monoplane with twin tails and tailwheel undercarriage.
The manufacturing process, however, was unorthodox, and the aircraft’s structures were built up from mahogany veneers bent over moulds and impregnated with vinyl and phenol resins to make them hold their shape. The Vidal plastic-bonded mahogany plywood construction. The use of metal for structural elements – even in fasteners – was thereby almost completely avoided.
Two prototypes were constructed, one with 65 hp (49 kW) engines NX29099, and another (29-90 NC/N51706) with 90 hp (67 kW) engines. The second machine was purchased by the United States Navy and evaluated as the XNL-1 39056, but the navy did not order the type. The Langley was a Type Certificated airplane, achieving ATC number 755.
Once the United States entered the war, it transpired that the resins needed for construction were in far shorter supply than the metal that would have been needed to produce an aircraft by conventional means, and the project was abandoned.
The XNL-1 was sold as war surplus. The Langley was landing in Oklahoma in 1965 and after touch down the brakes locked flipping the airplane over and damaging the fuselage beyond economical repair.
John Pierce and Hurley Boehler had a Stinson 108 fuselage in their hangar without wings, so they decided to purchase the Langley and, following the accident, its wings, engine nacelles, and main undercarriage were mated to a Stinson 108 fuselage to create a one-of-a-kind homebuilt aircraft named the Pierce Arrow N6622A.
2-4-65 Engines: 2 × Franklin 4AC, 65 hp (49 kW) Length: 20 ft 8 in (6.30 m) Wingspan: 35 ft 2 in (10.72 m) Maximum take-off weight: 1155 lb Maximum speed: 135 mph (216 km/h) Cruising speed: 185 kph Stall: 50 mph Range: 400 miles (640 km) Service ceiling: 13,300 ft (4,100 m) Take-off distance: 200 ft Crew: one pilot Capacity: three passengers
2-4-90 / NL-1 Engines: 2 × Franklin, 90 hp Wingspan: 35 ft 2 in (10.72 m) Length: 20 ft 8 in (6.30 m) Empty weight: 1738 lb Loaded weight: 2850 lb Maximum speed: 138 mph Cruising speed: 117 kph Stall: 55 mph Range: 350 miles at 100 mph ROC: 695 fpm Crew: one pilot Capacity: three passengers
Established in 1940 as Langley Aircraft Corp (pres: Caleb S Bragg). Langley Aircraft Corporation was based in Port Washington, NY, with director Martin Jensen and Arthur Draper.
In 1942 the company was acquired by Andover-Kent Aviation Co (pres: J J Brooks), New Brunswick NJ, but WW2 curtailed activity. After the company built the first airplane, two or three cars were released in 1942 under the license of “Andover-Kent Aviation Company”.
Built in 1908-1909, assembled and tested at Knockholt Cricket ground in Kent, it took off, but crashed on the first attempt and appears not to have been rebuilt. The fuselage was an open parallel girder, with curved top and bottom members meeting at both front and rear ends. Fitted with a tail plane and front elevator, there was considerable dihedral to the wings, which were braced to a tall pylon of four struts, and could be warped. The unidentified type of motor drove twin tractor propellers, apparently by shafts and bevel gearing.
Throughout the winter and spring months of 1894, work proceeded to complete No. 5 and retrofit No. 4 with a bigger set of wings. No. 5 was a large machine, with a wingspan of 13 feet 8 inches, length of 13 feet 2 inches and height of 4 feet 1 inch. Weighing 30 pounds, it was fitted with a new and more powerful single-cylinder steam engine. Trials resumed once again on October 7, 1894, after the summer layoff. The crew practiced using a new launching system. After a few throws with nonpowered “dummy” Aero¬dromes and some minor adjustments, the launcher seemed to be working perfectly. The rebuilt No. 4 was prepared for flight at once. Unlike pre¬vious attempts, the model launched perfectly, but then the wings twisted, plunging it into the water. Although it was late in the day, Aerodrorne No. 5 was read¬ied for a trial. Again, the launching system worked perfectly, but as the Aerodrome left the rail, it nosed up steeply, slowed and then slid backward into the Potomac. To everyone’s surprise, Langley was ec¬static. He thought he saw signs of pro¬gress for the first time. Over the next two months, Aerodromes No. 4 and 5 were launched numerous times. The launcher continued to work well, but the models just would not fly. By late November, the team had again re¬treated to the warmth of the Smithsonian’s shops, where serious static experiments were conducted to determine the strength of the wings. As Langley ordered, No.4 and No. 5 “were inverted, and sand was spread uniformly over the wings until its weight represented that of the machine.” Langley was shocked by the lack of stability and general weakness of the structure when loaded in that manner. More modifications were in order, including a new system of guy wiring for No.5. The changes to No.4 were so extensive that everyone felt jus¬tified in renaming it No. 6. The No.5 had a metal tube-fuselage structure that housed the engine, the boiler, and other components of the propulsion system. The wings and tail were wood-frame, covered with fine silk. The power plant was a single-cylinder, one-horsepower steam engine equipped with a double-action piston with a slide valve, and a flashtube boiler fired by a pressure burner that vaporized gasoline. The engine drove twin propellers, centrally mounted between the front and rear sets of wings, through a system of shafts and bevel gears. The aircraft weighed approximately 11kg (24.3 lb) ready for flight.
Quantico flight testing began again in early May 1895. Three attempts using No. 5 and No. 6 were considered failures. The longest time aloft was only six seconds.
After more than three years of inten¬sive work, Langley was feeling pressure from many sources to show better results. His critics were becoming more vocal. Having exhausted all the available brainpower within the Smithsonian, Langley decided to conduct an outside search for technical help. He found Au¬gustus Moore Herring.
Then came the watery failure of Aerodrome No. 6 on May 6, 1896. Soon afterward, having instructed his staff to ready No. 5 for a trial, Langley moved to a better vantage point on the shore of tiny Chopawamsic Island. This time, Edward Chalmers Huffaker was responsible for launching the machine. Forty-year-old Huffaker had earned a master’s degree in physics from the University of Virginia before becoming an aeronautical protégé of Octave Chanute. Impressed by Huffaker’s credentials, Langley had hired Edward to assist with the Aerodrome project. Later, because of Chanute’s influence, Huffaker was an invited guest of the Wright brothers for their 1901 gliding trials near Kitty Hawk, N.C.
Alexander Bell, the official observer, was on the port deck with a nervous Smithsonian photographer who had earlier missed taking a photograph of No. 6 splashing into the Po¬tomac. Langley had angrily told him not to let it happen again. When the steam pressure reached a predetermined 150 pounds, the signal was given to go. At 3:05 p.m., Aerodrome No. 5 cat¬apulted from the launch rail. Unlike earlier attempts, the throw was perfect – slightly nose high with its wings level. At first, the machine dropped three or four feet but then began to climb as it headed into a slight breeze from the north. The workmen, accustomed to hauling soaked and broken Aerodromes out of the water after a failure, were astounded to see the big drag¬onfly actually remain aloft. The machine started a gentle right turn, passing almost di¬rectly over Langley’s head. It continued flying this pattern until it reached a maximum estimated altitude of 80 feet. After about one minute and 20 seconds, the propellers suddenly stopped turning, probably from lack of steam to the engine. To every-one’s surprise, the model glided beautifully for another 10 sec¬onds before landing lightly on the surface of the bay, 425 feet from the houseboat. The Aerodrome had made three complete circles, each with an estimated diameter of 300 feet, as it drifted to the northwest. Calculations revealed that it had traveled about 3,300 feet in 90 seconds, generating a speed of between 20 and 25 mph.
The workmen retrieved the machine, then dried and care¬fully re-guyed the wings, one of which had sustained a kink. Langley believed that the shock of launching or the air pres¬sures of flight might have caused the problem. He also sug¬gested that the right-hand turn may have been caused by the wing’s misalignment. No.5 was ready to fly again within two hours. At exactly 5:10 p.m., the model was off on another successful flight. As before, the Aerodrome made three ascending circles to the right, reaching a maximum altitude of 60 feet. When the propellers finally stilled, the model pitched slightly nose down and glided ma¬jestically to a perfect water touchdown. Calculations showed it had flown about 2,300 feet.
On both occasions, the Aerodrome No.5 landed in the water, as planned, because, in order to save weight, it was not equipped with landing gear. On November 28, another successful flight was made with a similar model, the Aerodrome No.6. It flew a distance of approximately 1,460 m (4,790 ft).
The Aerodrome No.5 was transferred in 1905 from the research component of the Smithsonian to the United States National Museum, the entity of the Institution which at that time housed and cared for historical materials. The No.5 was first restored in 1975. When the aircraft was in need of restoration a second time in 1993, the wing structures were considered to be too fragile to support the new silk covering. The originals were placed in storage to preserve them and accurate reproduction wings were made for exhibition purposes. The rest of the aircraft is original.
No.5 Wingspan: 4.2 m (13 ft 9 in) Length: 4.0 m (13 ft 2 in) Height: 1.3 m (4 ft 3 in) Weight: 11.4 kg (25 lb)
Samuel Langley’s successful flights of his model Aerodromes Number 5 and Number 6 in 1896 led to plans to build a full-sized, human-carrying airplane. Langley’s simple approach was merely to scale up the unpiloted Aerodromes to human-carrying proportions. This would prove to be a grave error, as the aerodynamics, structural design, and control system of the smaller aircraft were not adaptable to a full-sized version. Langley’s primary focus was the power plant. The completed engine, a water-cooled five-cylinder radial that generated a remarkable 52.4 horsepower, was a great achievement for the time. This machine was a scaled-up petrol-engined version of a small steam-powered model flown with great success by Langley in 1896, and had been financed to the extent of $50,000 by the US War Department.
The Aerodrome has a steel tubing fuselage and wooden wings and tail. The covering was Percaline (a light-weight cotton) with a natural fabric finish; no sealant or paint of any kind.
Charles Manly (designer of the engine) attempted to fly from a houseboat on the Potomac River but despite the excellent engine, the Aerodrome A, as it was called, crashed on takeoff on October 7, 1903, and again on December 8. Langley blamed the launch mechanism. While this was in some small measure true, there is no denying that the Aerodrome A was an overly complex, structurally weak, aerodynamically unsound aircraft. This second crash ended Langley’s aeronautical work entirely.
8 December 1903
Glenn Curtiss rebuilt the Langley Aerodrome in 1914 and flew it as a seaplane. These flights were possible only because Curtiss made important changes in its design.
Engine: 5 cylinder radial, 52 hp. Propellers: two pusher propellers via geared transmission system Wingspan: 14.8 m (48 ft 5 in) Length: 16.0 m (52 ft 5 in) Height: 3.5 m (11 ft 4 in) Weight: 340 kg (750 lb), including pilot
The original Langley Flying Machine of 1903, in the opinion of many, this was the first heavier than air craft in the history of the world capable of sustained free flight under its own power, carrying a man.
Professor Samuel Pierpont Langley (1834-1906) was well known especially for his astronomical research. He became the third Secretary of the Smithsonian Institution in 1887. Langley had begun serious investigation into heavier-than-air flight several years earlier while at the then Western University of Pennsylvania in Pittsburgh. He had erected a huge, 18.3 m (60 ft) diameter whirling arm at the university’s Allegheny Observatory to perform aerodynamic research. At full speed, the tips of the whirling arm approached seventy miles per hour. Langley mostly ran tests with flat plates, but he also mounted small model airplanes he called aerostats, and even stuffed birds, on the arm. He also conducted an extensive series of experiments with rubber band-powered models.
Langley described these investigations and provided a summary of his results in Experiments in Aerodynamics, published in 1891. He then moved away from purely theoretical aerodynamic research, and began work aimed at engineering an actual flying machine. In 1891, he started to experiment with large, tandem-winged models powered by small steam and gasoline engines. Another large whirling arm, 9 m (29.5 ft) in diameter, was set up at the Smithsonian to test curved wing shapes and propellers, probably in connection with the design of these large powered models that Langley called aerodromes. After several failures with designs that were too fragile and under-powered to sustain themselves, he had success with Aerodrome No.5.
Like the original, the Langhurst replica Stuka is a two-place aircraft with a single control from the front seat. The rear seat faces the tail. The replica is completely of metal construction. Basically, it is a com¬posite. It has an inner steel-tube frame and an aluminum skin. Because the original rib type was unknown, Langhurst utilized the NACA 2415, which looks very much like the original.
The 7/10 Stuka is actually a full-sized airplane by most homebuilt standards. It has a full electrical system, full hydraulic system and complete fuel manage¬ment system. The landing gear and tailwheel units are standard from a PT-19.
Registered N87LL, the Stuka first flew on 19 July 1978.
The aircraft is now on loan to the San Diego Aerospace Museum.
First run in 1995, the Lange EA 42 is an electrical aero engine designed for self launching gliders. It is produced in Germany by Lange Aviation for their Antares 20E glider. Contents
The EA 42 combines an EM 42 brushless 42 kW electric external rotor motor with a related engine control system and power electronics. The motor drives a two-bladed composite fixed pitch propeller with a diameter of 2 m (7 ft). It is powered by a battery pack.
Applications: Lange Antares 20E Lange Antares 23E Schempp-Hirth Arcus E
Specifications: Power 38.5 kW
EM42 electrical engine Diameter 25 cm (10 in) Length 27.2 cm (11 in) Mass 29.12 kg (64 lb)
LE 42 power electronics Length 42.2 cm (17 in) Width 16.9 cm (7 in) Height 20.8 cm (8 in) Mass 9.58 kg (21 lb)