Tag Archives: Hall L. Hibbard

24 February 1934

The prototype Lockheed Model 10 Electra X233Y in flight over Southern California, 1934. (James Borden Photography Collection)

24 February 1934:¹ Edmund Turney Allen,² a consulting engineer and test pilot, took the prototype Lockheed Model 10 Electra, serial number 1001, registered X233Y, for its first flight from the Lockheed Aircraft Corporation plant in Burbank, California, to the adjacent United Airport (which soon became United Air Terminal, then Lockheed Air Terminal and is now the Hollywood-Burbank Airport, BUR).

Aerial photograph of United Airport, looking west northwest, early 1930s. The Lockheed factory is just out of frame at the lower left, bordering the railroad tracks. (Burbank Public Library)

The Los Angeles Times reported:

NEW-TYPE PLANE PERFECTED

Lockheed Factory Turns Out First of “Electras,” Latest Word in Swift Transport

     The latest forward step by Los Angeles in the field of swift-aircraft manufacture, a 215-mile-an-hour, ten-passenger, low-wing monoplane built by Lockheed Aircraft Corporation, made its first appearance and took to the air in its initial test flight yesterday.

     The all-metal airliner, one of the fastest multimotored transport planes in the world and designed for economical performance by airlines enjoying little or no air-mail subsidy, was flown by Edmund T. Allen on its maiden flight from the Lockheed plant to United Airport, Burbank.

     The ship, named the Electra, is the first of nine such planes ordered by two airlines, Northwest Airways having placed an order for three and Pan-American Airways awaiting delivery on six Electras. The model follows the single-engine Lockheed Vega, Orion and Sirius models flown by Col. Charles A. Lindbergh, Wiley Post, Col. Roscoe Turner, Amelia Earhart and other noted flyers on record flights.

     The Electra’s cruising speed is in excess of 190 miles per hour. It is equipped with controllable-pitch propellers to gain maximum efficiency from its two Wasp Junior engines supercharged to develop 420 horsepower each at 5000 feet.

     The craft is equipped with advanced improvements, including new retractable landing gear, wing flaps to insure low, safe landing speed, and a radical new-type tail assembly having two small vertical fins, or rudders,instead of one large one, making for greater maneuverability.

     The Electra will be on display at United Airport, and the public, according to United Airlines officials, is invited to inspect it.

Los Angeles Times, Vol. LIII, 25 February 1934, Page 17, Columns 1 and 2

The prototype Lockheed Electra Model 10 prototype, X233Y, at Union Airport, Burbank, California, before its first flight, 24 February 1934. (James Borden Photography Collection)

The Lockheed Model 10 Electra was designed as a 10-passenger commercial transport and was a contemporary of the Boeing Model 247. This was Lockheed’s first all-metal airplane. The Electra had two engines, a low wing and retractable landing gear. The airplane was designed by Lloyd Stearman and Hall L. Hibbard.

Lockheed Model 10 Electra X233Y. (aviadejavu)

A young engineer, Clarence L. (“Kelly”) Johnson, an assistant aerodynamicist at the University of Michigan, performed the wind tunnel tests on scale models of the proposed design and recommended changes to the configuration, such as the use of two vertical fins mounted at the outboard ends of the horizontal stabilizer. This became a design feature of Lockheed airplanes into the 1950s and included the Model 14 Super Electra/Hudson, Model 18 Lodestar/PV-1 Ventura, the P-38 Lightning fighter and the L-1649 Starliner, which was produced until 1958. Johnson would become the leader of Lockheed’s legendary  “Skunk Works.”

Clarence L. "KellY" Johnson conducted wind tunnel testing of the Model 10 at the University of Michigan.
Clarence L. “Kelly” Johnson conducted wind tunnel testing of the Model 10 at the University of Michigan. Note the single vertical fin on this wind tunnel model. (Lockheed)

The prototype Electra was was used for certification testing. During a full-load test at Mines Field (now, LAX, Los Angeles International Airport) the Electra’s landing gear malfunctioned. Marshall (“Babe”) Headle, Lockheed’s chief pilot, flew the airplane back to Burbank and made a one-wheel landing. The prototype was slightly damaged but quickly repaired.

Lockheed Model 10 Electra X233Y at Union Airport, Burbank, California, before its first flight, 24 February 1934. (James Borden Photography Collection)
Lockheed Model 10 Electra X233Y at Union Airport, Burbank, California, before its first flight, 24 February 1934. (James Borden Photography Collection)
Lockheed Model 10 Electra X233Y at Union Airport, Burbank, California, before its first flight, 24 February 1934. (James Borden Photography Collection)
Passenger cabin of the Lockheed Model 10 Electra, looking forward. (James Borden Photography Collection)
Lockheed Model 10 Electra NC233Y at Northwest Airways, St. Paul, Minnesota, May 1934. (James Borden Photography Collection)
Lockheed Model 10 Electra NC233Y, Northwest Airways, St. Paul, Minnesota, 24 May 1934. (James Borden Photography Collection)
Lockheed Model 10 Electra NC233Y, St. Paul Minnesota, 24 May 1934. (James Borden Photography Collection)

After testing was competed the prototype Electra was delivered to Northwest Airways, Inc., at St. Paul, Minnesota, in May 1934. The experimental registration was changed to a standard registration, NC233Y, and it was assigned the Northwest fleet number 60.

Like the Boeing 247, the Electra was originally produced with a forward-slanting windshield to prevent instrument light reflection during night flights. This resulted in ground lighting reflections, though, and was changed to a standard, rearward slant with the fifth production airplane. NC233Y was modified by Northwestern’s maintenance staff.

Lockheed built 147 Model 10s in various configurations. The first production variant was the Model 10A. It was 38 feet, 7 inches (11.760 meters) long with a wingspan of 55 feet (16.764 meters), and height of 10 feet, 1 inch (3.073 meters). The wings had a total area of 458.3 square feet (42.6square meters). Their angle of incidence was 0°, and there were 5° 34′ dihedral.

The airplane had an empty weight of 5,455 pounds (2,474 kilograms) and a gross weight of 9,000 pounds (4,082 kilograms).

Three-view illustration of initial configuration of the Lockheed Model 10 Electra.

The Model 10A was powered by two air-cooled, supercharged, 986.749-cubic-inch-displacement (16.170 liters) Pratt & Whitney Wasp Jr. SB  9-cylinder radial engines with a compression ratio of 6:1. They were rated at 400 horsepower at 2,200 r.p.m at 5,000 feet (1,524 meters), and 450 horsepower at 2,300 r.p.m. for takeoff, using 87-octane gasoline. The SB engines were direct-drive and turned two-bladed Smith variable-pitch propellers. The Wasp Jr. SB was 3 feet, 6.59 inches (1.056 meters) long, 3 feet, 11.75 inches (1.162 meters) in diameter, and weighed 645 pounds (293 kilograms). The engines were covered by NACA cowlings.

The airplane had a cruise speed of 190 miles per hour (306 kilometers per hour) at 5,000 feet (1,524 meters) and maximum speed of 215 miles per hour (346 kilometers per hour) at 8,000 feet (2,438 meters). The service ceiling was 20,000 feet (6,096 meters) and the range at cruise speed was 750 miles (1,207 kilometers).

The prototype Lockheed Model 10 Electra, NC233Y, after cockpit windshield modifications by Northwestern Airways, Inc. (San Diego Air and Space Museum Archives)
The prototype Lockheed Model 10 Electra, NC233Y, after cockpit windshield modifications by Northwest Airways, Inc. (San Diego Air and Space Museum Archive, Catalog #: 01_00091576)

Newsreel footage of the Lockheed Model 10 prototype’s first flight, by cinematographer Alfred Dillimtash Black for Fox Movietone News, is in the collection of the Moving Image Research Collections, University of South Carolina, University Libraries, and can be viewed at: https://digital.tcl.sc.edu/digital/collection/MVTN/id/7073

The Electra was “the Lisbon plane” in the  classic 1942 motion picture, “Casablanca,” which starred Humphrey Bogart, Ingrid Bergman, Paul Henreid and Claude Rains.

Probably the best-known Lockheed Electra is the Model 10E Special, NR16020, which was built for Amelia Earhart for her around-the-world flight attempt in 1937. She took delivery of the airplane on her 39th birthday, 24 July 1936.

Amelia Earhart with her Lockheed Electra 10E, NR16020, at Burbank, 1937.
Amelia Earhart with her Lockheed Electra 10E, NR16020, at Burbank, 1937.

The prototype Lockheed Model 10 later carried U.S. registrations NC2332, NC17380, and Canadian registration CF-BRG. It was placed in service with the Royal Canadian Air Force 2 August 1940 with the serial number 7652. One of 15 Lockheed Electras in RCAF service during World War II, it was destroyed by fire at RCAF Station Mountain View, Prince Edward County, Ontario, Canada, 14 October 1941.

Statement of Accident (Royal Canadian Air Force/Canadian Warplane Heritage Museum)

¹ Most sources cite 23 February as the date of the first flight.

² Many sources (e.g., Wikipedia) state that Lockheed’s Chief Pilot, Marshall Headle, made the Electra’s first flight.

© 2023, Bryan R. Swopes

27 January 1939

Lockheed XP-38 Lightning 37-457 at March Field, Riverside County, California, January 1939. (San Diego Air and Space Museum)
Lockheed XP-38 Lightning 37-457 at March Field, Riverside County, California, January 1939. (San Diego Air and Space Museum Archive)

27 January 1939: First Lieutenant Benjamin Scovill Kelsey, Air Corps, United States Army, made the first flight of the prototype Lockheed XP-38 Lightning, serial number 37-457, at March Field, Riverside County, California.

This was a short flight. Immediately after takeoff, Kelsey felt severe vibrations in the airframe. Three of four flap support rods had failed, leaving the flaps unusable.

1st Lieutenant Benjamin Scovill Kelsey, Air Corps, United States Army, 1937.

Returning to March Field, Kelsey landed at a very high speed with a 18° nose up angle. The tail dragged on the runway. Damage was minor and the problem was quickly solved.

Designed by an engineering team led by Hall L. Hibbard, which included the legendary Clarence L. “Kelly” Johnson, the XP-38 was a single-place, twin-engine fighter designed for very high speed and long range. It was an unusual configuration with the cockpit and armament in a center nacelle, with two longitudinal booms containing the engines and propellers, turbochargers, radiators and coolers. The Lightning was equipped with tricycle landing gear. The nose strut retracted into the center nacelle and the two main gear struts retracted into bays in the booms. To reduce drag, the sheet metal used butt joints with flush rivets.

The prototype had been built built at Lockheed’s factory in Burbank, California. On the night of 31 December 1938/1 January 1939, it was transported to March Field aboard a convoy of three trucks. Once there, the components were assembled by Lockheed technicians working under tight security.

Lockheed XP-38 Lightning 37-457. (San Diego Air and Space Museum)
Lockheed XP-38 Lightning 37-457. (San Diego Air and Space Museum Archive)
Lockheed XP-38 Lightning 37-457. (San Diego Air and Space Museum Archive)
Left profile, Lockheed XP-38 Lightning 37-457. (U.S. Air Force)
Left profile, Lockheed XP-38 Lightning 37-457. (U.S. Air Force)
Lockheed XP-38 Lightning 37-457

The XP-38 was 37 feet, 10 inches (11.532 meters) long with a wingspan of 52 feet (15.850 meters) and overall height of 12 feet, 10 inches (3.952 meters). Its empty weight was 11,507 pounds (5,219.5 kilograms). The gross weight was 13,904 pounds (6,306.75 kilograms) and maximum takeoff weight was 15,416 pounds (6,992.6 kilograms).

The Lightning was the first production airplane to use the Harold Caminez-designed, liquid-cooled, supercharged, 1,710.60-cubic-inch-displacement (28.032 liter) Allison Engineering Company V-1710 single overhead cam 60° V-12 engines. When installed on the P-38, these engines rotated in opposite directions. The XP-38 used a pair of experimental C-series Allisons, with the port V-1710-C8 (V-1710-11) engine being a normal right-hand tractor configuration, while the starboard engine, the V-1710-C9 (V-1710-15), was a left-hand tractor. Through a 2:1 gear reduction, these engines drove the 11-foot (3.353 meters) diameter, three-bladed Curtiss Electric variable-pitch propellers inward to counteract the torque effect of the engines and propellers. (Viewed from the front of the airplane, the XP-38’s starboard propeller turned clockwise, the port propeller turned counter-clockwise. The direction of rotation was reversed in the YP-38 service test prototypes and production P-38 models.) The engines have long propeller gear drive sections to aid in streamlining aircraft, and are sometimes referred to as “long-nose Allisons.”

The V-1710-11 and -15 had a compression ratio of 6.65:1. They had a continuous power rating of 1,000 horsepower at 2,600 r.p.m. at Sea Level, and 1,150 horsepower at 2,950 r.p.m. for takeoff. The combination of a gear-driven supercharger and an exhaust-driven General Electric B-1 turbosupercharger allowed these engines to maintain their rated power levels to an altitude of 25,000 feet (7,620 meters).

The -11 and -15 were 7 feet, 10.46 inches (2.399 meters) long. The -11 was 3 feet, 6.59 inches (1.082 meters) high and 2 feet, 4.93 inches (0.7348 meters) wide. It weighed 1,300 pounds (589.7 kilograms). The -15 was 3 feet, 4.71 inches (1.034 meters) high, 2 feet, 4.94 inches (0.7351 meters) wide, and weighed 1,305 pounds (591.9 kilograms).

A 1939 Allison Engine Company V-1710-33 liquid-cooled, supercharged SOHC 60° V-12 aircraft engine at the Smithsonian Institution National Air and Space Museum. This engine weighs 1,340 pounds (607.8 kilograms) and produced 1,040 horsepower at 2,800 r.p.m. During World War II, this engine cost $19,000. (NASM)
A 1939 Allison Engine Company V-1710-33 liquid-cooled, supercharged SOHC 60° V-12 aircraft engine at the Smithsonian Institution National Air and Space Museum. This engine weighs 1,340 pounds (607.8 kilograms) and produced 1,040 horsepower at 2,800 r.p.m. During World War II, this engine cost $19,000. (NASM)

The XP-38 had a maximum speed of 413 miles per hour (664.66 kilometers per hour) at 20,000 feet (6,096 meters) and a service ceiling of 38,000 feet (11,582.4 meters).

The XP-38 was unarmed, but almost all production Lightnings carried a 20 mm auto cannon and four Browning .50-caliber machine guns grouped together in the nose. They could also carry bombs or rockets and jettisonable external fuel tanks.

Lockheed XP-38 37-457. (San Diego Air and Space Museum Archive)
Lockheed XP-38 37-457. (San Diego Air and Space Museum Archive)

The prototype XP-38 was damaged beyond repair when, on approach to Mitchel Field, New York, 11 February 1939, both engines failed to accelerate from idle due to carburetor icing. Unable to maintain altitude, Lieutenant Kelsey crash landed on a golf course and was unhurt.

Testing continued with thirteen YP-38A pre-production aircraft and was quickly placed in full production. The P-38 Lightning was one of the most successful combat aircraft of World War II. By the end of the war, Lockheed had built 10,037 Lightnings.

Lockheed test pilot Tony LeVier in the cockpit of P-38J-10-LO Lightning 42-68008. (Lockheed Martin)

© 2019, Bryan R. Swopes