Northrop YC-19/Y1C-19 Alpha
Single-engine five-place Military VIP transport monoplane

Archive Photos

Northrop Y1C-19 Alpha (A.C. 31-518) NASA and Northrop historic photos

Overview

The Northrop YC-19 Alpha and Y1C-19 Alpha was a series of three aircraft purchased from Northrop by the US Army Air Corps in 1931. They were slightly modified versions of the civil Northrop Alpha 2. The major difference between the C-19s and the Alphas was that the civilian version carried a pilot and six passengers while the Army version carried a pilot and four passengers. One aircraft, the last of the three purchased, crashed between Richmond and Petersburg, Virginia on Sunday, March 19, 1933, killing its pilot and two passengers. The other aircraft were used for several more years until being sent to training schools as subjects for maintenance and repair classes.

Northrop Alpha Series

The Northrop Alpha was an American single-engine, all-metal, seven-seat, low-wing monoplane fast mail/passenger transport aircraft used in the 1930s. Design work was done at the Avion Corporation, which in 1929, became the Northrop Aircraft Corporation based in Burbank, CA.

Design & Development

Drawing on his experience with the Lockheed Vega, John K. Northrop designed an advanced mail/passenger transport aircraft. In addition to all-metal construction, the new Alpha benefitted from two revolutionary aerodynamic advancements: wing fillets researched at the Guggenheim Aeronautical Laboratory at the CA Institute of Technology, and a multicellular stressed-skin wing of Northrop’s own design which was later successfully used on Douglas DC-2 and Douglas DC-3. In addition, the Alpha was the first commercial aircraft to use rubber deicer boots on wing and empennage leading edges which, in conjunction with state-of-the-art radio navigation equipment, gave it day or night, all-weather capability. The aircraft first flew in 1930, with a total of 17 built. The Alpha was further developed into a dedicated fast transport Northrop Gamma.

Operational History

The Alpha entered service with Transcontinental & Western Air (future TWA) making its inaugural flight on 20 April 1931. The trip from San Francisco to New York required 13 stops and took just over 23 hours. TWA operated 14 aircraft until 1935, flying routes with stops in San Francisco, CA; Winslow, Arizona; Albuquerque, New Mexico; Amarillo, Texas; Wichita, Kansas; Kansas City, Missouri; St. Louis, Missouri; Terre Haute, Indiana; Indianapolis, Indiana; Columbus, Ohio; Pittsburgh, Pennsylvania; Philadelphia, Pennsylvania; and New York. Three Alphas were operated by the US military as C-19 VIP transports until 1939.

The third Alpha built, NC11Y, was re-acquired by TWA in 1975, and is preserved at the Smithsonian National Air and Space Museum.

Variants

• Northrop Alpha 2: Seven-place (six-passenger) closed-cabin land monoplane.
• Northrop Alpha 3: One/three-place (two-passenger plus cargo) closed-cabin land monoplane. Several Alpha 2s were converted to this configuration.
• Northrop Alpha 4: One-place open-cockpit land monoplane cargo version with 2 ft (0.6 m) increased wingspan, all converted from Alpha 3s.
• Northrop Alpha 4A: One-place open cockpit land monoplane cargo version, all converted from Alpha 4s.
• Northrop YC-19 & Y1C-19: USAAC military VIP transport, seating reduced to 4 passengers, serial numbers 31-516 to 31-518, YC-19 had a Pratt & Whitney R-1340-7, while the Y1C-19s had the R-1340-11 engine.

Operators

• United States
• Trans World Airlines
• US Army Air Corps

Northrop YC-19/Y1C-19 Alpha Specifications and Performance Data

Type

• Five-place (four-passenger) closed-cabin all-metal military VIP land monoplane.

Wings

• Low-wing cantilever monoplane.
• Outer sections are attached to short wing stubs, which are built integral with the fuselage.
• Outer sections are of the multi-cellular stressed-skin type and are built entirely of Alclad.

Fuselage

• Oval section structure, monocoque construction.
• A smooth Alclad skin, with integrally-formed longitudinal stiffeners, carries the entire fuselage stresses.
• The structure is strengthened with ring-shaped bulkheads built up with a channel cross-section.

Tail Unit

• Normal monoplane type.
• It is of all-metal construction and entirely cantilever.
• The structure is of the multi-cellular type, as used in the wings.

Undercarriage

• Divided type.
• Consists of two Vees, incorporating oleo and rubber-in-compression springing, attached to the extremities of the wing stubs and two axles, the inner ends of which are hinged to the center-line of the underside of the fuselage.
• Wheel-brakes and full swiveling tail-wheel.
• Wheel undercarriage interchangeable with floats.

Power Plant

• YC-19: One 450 Hp Pratt & Whitney R-1340-7 Wasp air-cooled radial engine, enclosed in an NACA cowling.
• Y1C-19: One 450 Hp Pratt & Whitney R-1340-11 Wasp air-cooled radial engine, enclosed in an NACA cowling.
• Fuel tanks (two) are carried in the wing stubs.

Accommodation

• Enclosed cabin for four VIP military passengers over the wing.
• Open pilot cockpit located aft of the cabin and the rear baggage compartment.
• Cubic capacity of the cabin is 120 ft³.
• Standard equipment consists of a hand inertia-starter, navigation lights, rate of climb and turn and bank indicators, in addition to the usual instruments.
• Special equipment such as generator, landing lights, flares and wireless can be installed if desired, at slight extra cost.

Dimensions

• Wingspan: 41 feet, 10 inches
• Wing area: 312 ft²
• Length: 28 feet, 5 inches
• Height: 9 feet, 0 inches

Weights and Loadings

• Weight empty: 2,800 lbs
• Weight loaded: 4,700 lbs
• Wing loading: 15.06 lb/ft²
• Power loading: 10.44 lbs/hp

Performance

• Maximum speed: 170 mph
• Cruising speed: 155 mph
• Service ceiling: 19,000 ft
• Range: 650 miles

References

• 3-view drawing: John Shupek
• Historic Photos: NASA and Northrop
• Grey, C. G. and Bridgman, Leonard, Jane’s All The World’s Aircraft 1931, Sampson Low, Marston & Company, Ltd., London, 1931, pp. 303c-304c
• Holder, Bill and Vadnais, Scott, The C Planes, U.S. Cargo Aircraft: 1925-To The Present, Schiffer Military/Aviation History, Atglen, PA, 1996, ISBN: 0-88740-912-1, pp. 16
• Allen, Richard Sanders, The Northrop Story 1929-1939, Orion Books, New York, 1990, ISBN 0-517-56677-X, pp. 154-155
• Aeronautical Chamber of Commerce of America, Inc., The Aircraft Year Book For 1931, D. Van Nostrand Company, Inc., New York, 1931, pp. 337
• Wikipedia: Northrop Alpha
• Wikipedia: Northrop C-19 Alpha