Around this time, the late 1930s Lockheed Aircraft Corporation was studying different airliner projects. The first was the Model 27, which had a canard configuration. The other two were the L-104 and L-105. The L-105 was smaller, with 1200 hp engines, and was more conventional than the L-104. These studies led Lockheed’s Burbank facility to settle on a design dubbed Model 44, a four-engined airliner that was announced to the public in April 1939. Soon afterwards, the new airliner was dubbed Excalibur. The Excalibur resembled an enlarged Model 10 Electra. It would be powered by four Wright GR-1820 Cyclone 9 radial engines, rated at 1000 hp (746 kW), or four Pratt & Whitney R-1830 Twin Wasp radials. Its wingspan was 95 ft 9 in (29.18 m), its length was 82 ft 6 in (25.15 m), and its projected maximum speed was in the 250-280 mph range (402–451 km/h). Several variants were proposed, to accommodate different passenger loads.
The original Excalibur design envisioned a 21-passenger payload, with a 240 mph (386 km/h) cruising speed. This was revised to 36 passengers at 268 mph (431 km/h) cruise at 12,000 feet (3,660m) altitude. This change included increasing the fuselage diameter, making it comparable to the Model 18 Lodestar, and increasing the wingspan to 95 ft 9 in (25.19 m) with an area of 1,000 ft² (92.9 m²). A tricycle landing gear with steerable nosewheel was envisioned. With the revised specifications, the Excalibur could now effectively compete with the near monopoly Douglas had on the airliner market. Its projected performance was better (except in range) than the Boeing 307. The revision of specifications was partially due to a request from Pan American Airlines; their influence also caused the addition of the third tailfin. A variant designated the L-144, able to carry 40 passengers was planned, but was ultimately cancelled even though South African Airways had placed a potential order for two examples. Lockheed proceeded with a full-scale mockup of the proposed Excalibur, including most of the airliner except the right wing.
The billionaire Howard Hughes, who had recently gained ownership of Transcontinental & Western Air (TWA), decided to provide funding for the new Excalibur. He had a plan in mind to vastly improve the characteristics of the Excalibur by increasing comfort, speed and profit of the aircraft. It was thus that Hughes invited three workers from Lockheed and Jack Frye (president of TWA) to a meeting at his Hancock Park residence. The Lockheed employees included Clarence “Kelly” Johnson and Robert E. Gross. Hughes expressed his requirements for the “airliner of the future”: a payload of 36 passengers (or 20 sleeping berths), a six-person crew, a 3,600 mile (5,800 km) range, a 300 mph (483 km/h) cruise speed, and a weight of 23.5-25 metric tonnes. This meant that the Excalibur would have to get a 100 mph (161 km/h) increase in speed and be able to fly 1,000 ft (305 m) higher. It would need to cross the United States nonstop. The first decision was to re-engine the Excalibur with Wright R-2600 radials, which had not been tested yet. The next decision was to start from scratch while saving the overall shape and triple tail configuration of the original Excalibur.
The new design differed so much from the original Excalibur, that a different model designation was needed. It was first given the temporary designation L-104, then it was later officially designated the Model 49 or “Excalibur A”. In time, the Model 49 would become a completely different aircraft from the original Model 44. Lockheed later dropped the name “Excalibur” as the new airliner had little to do with its predecessor. The end result was the Lockheed L-049 Constellation.
Powerplant: 4 × Pratt & Whitney Twin Wasp S4C-4-G, 1200 hp (895 kW) each Wingspan: 95 ft 0 in (28.96 m) Wing area: 1000 sq.ft (92.90 sq.m) Aspect ratio: 9.025 Length: 74 ft 11½ in (22.85 m) Empty weight: 26,424 lb (11,986 kg) Gross weight: 40,000 lb (18,144 kg) Crew: two Capacity: 32 passengers
The Vega Starliner NX21725 was a five/six-seat low-wing cabin monoplane with retractable landing gear and an unusual powerplant. The model 22 was a modification with 640hp Menasco Unitwin 2-544 and a single tail. This comprised two 194kW Menasco C6S-4 inline engines, mounted side-by-side, and coupled to drive together, or independently in emergency, a single propeller.
First flown on 22 April 1939 (piloted by B A Martin), the Starliner was abandoned after some 85 flight test hours as there was no demand for an aircraft in this category.
Vega Starliner NX21725
The aircraft was sold to a film studio and its track faded.
Engines: two 194kW Menasco C6S-4 Unitwin Wingspan: 12.50 m / 41 ft 0 in Length: 31’6″ Max take-off weight: 2722 kg / 6001 lb Useful load: 1660 lb Max. speed: 338 km/h / 210 mph Cruise speed: 180 mph Stall: 60 mph Range: 600 mi Seats: 6
Designed to compete against the DST/ DC-2/DC-3 series being developed by the Douglas company, the Lockheed 14 Super Electra failed to be any significant competition, due to its smaller capacity. Of the same general configuration as the earlier Lockheed 10 Electra, it differed by having a much deeper fuselage accommodating a maximum of 14 passengers, a mid-set wing, and introduced integral fuel tanks in the wing, Fowler-type trailing-edge flaps, fully-feathering propellers and, at a later stage of production, fixed wing slats. These improvements, combined with powerful engines and high wing loading, gave the Super Electra excellent performance but, by comparison with the important and larger-capacity Douglas DC-3, it was less efficient in operation.
First flown in prototype form on 29 July 1937 powered by two 760hp Wright Cyclone radial engines, and certificated on 15 November 1937, initial deliveries were made shortly afterwards.
Howard Huges and 4 crew flew around the world in 3 days 19 hr 14 min in Lockheed 14 New York World’s Fair 1939.
A British Purchasing Commission visited the United States in April 1938, intent on acquiring a substantial number of American military aircraft. Lockheed executives and designers got together when they knew the British team was on its way looking for warplanes and in ten days and nights drawings were produced, and a wooden mock up constructed, of the Model 14 in its converted form of a reconnaissance bomber.
Suitably impressed Lockheed officials met Air Ministry chiefs in London, and on June 23, 1938, a contract was signed for the building of 175 aircraft, with as many more as could be delivered by December 1939, up to a maximum of 250. By the end of 1941 the order had gone up to 1700.
Named Hudson for RAF service, the first example (N7205) made its initial flight on December 10, 1938. Despite problems with tooling, the 250th machine was rolled out at Burbank over seven weeks ahead of schedule, thanks to staff increases and three shift working.
Initially Hudsons were delivered crated aboard ship, the first arriving at Liverpool Docks on February 15,1939, and then assembled at nearby Speke airport, where Lockheed established a subsidiary firm to undertake the rapidly increasing work consequential to the numbers of Hudsons arriving. By the summer of 1940, this amounted to over 200 aircraft. A British installation, when the Hudsons arrived, was a Boulton & Paul power operated dorsal gun turret housing two .303 in Browning machine guns.
On Sunday 8 October 1939: During a patrol flight over the North Sea, a Lockheed Hudson coastal reconnaissance plane of 224 Sqn became the first English aircraft to shoot down a German plane, a Dornier Do.18 flying boat.
In November 1940, because Britain needed aircraft urgently, seven Hudsons were flown from Newfoundland to Ireland. This led to the founding of the Atlantic Ferry Service. Pilots were flown from Britain to Newfoundland. There each of them obtained a new aircraft and flew it to Britain. By Christmas Eve 1943 1000 had been ferried across the Atlantic.
Main differences to the civil passenger version was the glazed nose position, dorsal turret and the bomb bay within the centre fuselage. In addition to the dorsal turret armament, Hudsons carried twin .303 in Browning guns fixed to fire forward from the top of the forward fuselage, and provision for two Vickers ‘K’ guns, one each side in beam positions. On earlier models the bomb load was 750 lb, but later variants were capable of carrying up to 1,400 lbs of bombs or depth charges.
The Hudson I was powered by two 745.2kW Wright GR-1820-G102A Cyclone engines driving Hamilton-Standard two-position propellers. It first entered service with Coastal Command, RAF in mid-1939. The British order for 250 Mk Is was increased to 350, followed by a contract for 20 Mk IIs with Hamilton-Standard Hydromatic constant-speed propellers, 414 Mk IIIs following.
The Hudson III represented the first major revision, having 1,200hp / 894kW GR-1820-G205A Cyclone engines with Hydromatic propellers and a retractable rear-firing ventral gun position. Large numbers of the Hudson III were delivered to the RAF under Lease-Lend (resulting in the use of the USAAF designation A-29) with 894kW Wright R-1820-87 Cyclone engines. Like earlier Hudsons, the Mk III was basically a maritime-patrol bomber and reconnaissance aircraft, but A-29A were fitted with benches for troop carrying. A-29/29A were also used by the USAAF and by the US Navy (as PBO-1).
The Hudson III armament consisted of a maximum bomb load of 1,600lb (726kg) comprising four 250lb (113kg) and six 100lb (45kg) bombs; two fixed Browning 0.303in machine guns in upper nose with 500rpg; one optional Vickers 0.303in machine gun in retractable ventral hatch with 500 rounds; two optional Vickers 0.303in beam machine guns in rear fuselage with 500rpg; two Browning 0.303in machine guns in dorsal Boulton Paul turret with 1,000rpg.
Initially the Mk IIIs had little advantage in range, but after some 150 had been built, extra fuel tanks were fitted, and on November 11, 1940, seven Hudson Mk IIIs flew direct from Gander, Newfoundland, to Aldergrove, Northern Ireland, in 10.5 hours. From then on all Hudsons were flown across the Atlantic on their delivery flights.
One Hudson Mk III was presented to the RAF free, the materials for this aircraft (T9465) having been supplied by Lockheed ‘gratis’ while employees gave their time free. This particular aeroplane was named Spirit of Lockheed Vega Employees, and was handed over to the British Ambassador in front of assembled Lockheed staff. This machine was allotted to 269 Squadron.
At the end of January 1940, Hudsons were the first aircraft in RAF Coastal Command to be fitted with air to surface vessel (ASV) radar, which was to prove so effective against sub¬marines when trying to locate them at night and in bad weather.
Hudsons also flew top secret Scrutator flights between Britain and Sweden. These operations involved taking items of freight, mail and often passengers to Stockholm, while on the return flights, the supply of Swedish ball bearings, made to a very high standard and vital to British war production, was maintained. Passengers were also flown back from Sweden diplomats, escaped Allied prisoners of war and even people who had managed to escape from the clutches of the Gestapo.
Hudsons used on Scrutator were specially converted Mk IIIs and came under the control of BOAC and, although camouflaged, carried civil registrations coming under the BOAC Loch class. Four Hudsons flew this crossing.
The Hudson III was the first aeroplane to be fitted to carry the British-developed Mk I airborne lifeboat. This lifeboat was first used operationally in May 1943 by an RAF air/sea-rescue squadron to rescue the crew of a downed bomber in the North Sea.
In RAF service the Hudson Mk III was followed by the Mk IIIA, first type to be sent under the Lend Lease scheme.
The Hudson IV was produced for the RAAF, with the ventral gun removed but received a D/F loop aerial in a transparent blister. The Air Corps assigned the A-28 designation to a contract for 52 aircraft to be delivered to the Royal Australian Air Force. Although U.S. serial numbers were given to the A-28s, none entered service with the U.S. Army Air Corps. All were delivered to the RAAF under the designation Hudson Mk.IVA and given RAAF serial numbers A16-101 to A16-152.
Thirty Hudson Mk IVs were diverted to the RAF from an Australian contract, followed by 309 Mk Vs and 450 Mk VIs, all these variants having 1,200hp Pratt & Whitney R-1830-SC3G Twin Wasp radials. The Hudson V for the RAF had R-1830-S3G4G engines driving Hamilton-Standard two-position propellers and a retractable ventral gun (as fitted to the Mk III).
The final version was the Hudson VI (designated A-28 by the USAAF) which was convertible to troop transport or cargo carrier with the turret removed. An improved version, designated A-28A, was built for export to the British Commonwealth under Lend-Lease agreements.
By 1943 RAF Hudsons were active in the Mediterranean and Middle East areas, having already flown convoy patrols the previous November to help cover the Allied landings in North Africa.
The Royal Australian Air Force received 247 Hudson’s between January 1940 and May 1942 in several versions.
Although 800 were ordered for the RAF, only 382 were delivered, the remainder going to the USAAF as the A 29, while some ended up with the US Navy as PBO-1 patrol bombers operating in the Caribbean area on anti submarine duties, USAAF machines did not usually have the power operated turret, but instead a single .50 in gun was installed on a flexible mounting in an open position with a shield for the gunner’s back. The A 29 could carry a 1,600 lb bomb load, and on July 7, 1942, the German submarine U 701 was attacked and sunk by one of these aircraft. US Navy PBO 1s sank two German U Boats, both during March 1942.
Orders for Hudsons were not only for the RAF, US Army Air Corps, US Navy and Australia, but also the air forces of Canada, New Zealand, and Nationalist China.
A total of 119 was licence-built in Japan by Kawasaki and Tachikawa. These, powered by 671kW Mitsubishi Ha-26-l radial engines, were designated Army Type LO Transport and were later allocated the Allied code name ‘Thelma’. The Japanese army introduced the first cargo transport, the Kawasaki Type 1, in 1941. The aircraft was a military version of the 13 passenger Lockheed 14 airliner and it had a maximum payload of only 3 metric tons.
Thelma
In 1938 Japan used both imported and domestic models as civil freight and mail transport. The civil models were coded ‘Toby, later dropped in favour of Thelma.
Toby
On 14 February 1942, units of the Japanese 38th Division landed on Sumatra north of Palembang, under cover from carrier-based aircraft and a strong cruiser formation under Vice-Admiral Ozawa. Japanese paratroops landed at the same time. At 6.00pm, approximately 70 aircraft of the American Lockheed 14 WG-3 design which had been built under licence before the war by Tachikawa and Kawasaki for the Japanese Army, and given them the name Ro-Shiki, dropped some 700 paratroops on the island. The aircraft had been painted olive green to look like RAF planes, they carried British national emblems and were almost indistinguishable from British Hudson bombers.
The aim of the operation was to seize the Palembang airfields, and above all, two large refinery plants at Pladyu and Sungai 4 miles east of the city at the mouth of the Komering river. The assault on Palembang airfield proved successful but the Japanese gained less than they hoped for. Approximately 16 of the simulated RAF Hudsons, many still full of paratroops, were shot down by flak artillery posted near the refineries, and the paratroops who landed in and around the installation were wiped out.
After withdrawal from combatant service with the RAF, USAAF and US Navy, the Hudson continued to be used for miscellaneous duties, including transport, air/sea rescue, training, target-towing, etc.
The Lockheed AT-18 was an advanced trainer based on the Lockheed Hudson. The USAAF placed an order for 300 AT-18s on 8 May 1942. All 300 aircraft were powered by 1,200hp Wright R-1820-87 engines. Production was split into two blocks. 217 aircraft were produced as AT-18-LO gunnery trainers, equipped with a Martin dorsal turret armed with twin 0.50in machine guns, while the remaining 83 aircraft were produced as AT-18A-LO navigational trainers. These aircraft had the turret removed and had space for the pilot, the instructor and three students.
On Wednesday 27 August 1941, a Hudson of 296 Sqn, RAF Coastal Command, under Sqn.Ldr. J.H. Thompson, attacked German U-boat U-570 under Naval Lt.Col. Ramlow in the North Atlantic despite poor weather conditions. The damaged U-boat, unable to manoeuvre, drifted along on the surface, and the commander had to surrender to the aircraft. Thompson radioed for support and was sent a PBY Catalina of 209 Sqn. Two destroyers and several trawlers also arrived. Next day the U-boat was towed to Iceland and three weeks latered entered British service as HMS Graph under Lt. Colvin.
By the time production ended in mid-1943, a total of 2,941 examples had been built, only 112 were built by Lockheed.
L.14 Super Electra Engines: 2 x 760 hp Wright Cyclone Length: 44.2 ft (13.4 m) Wing span: 65.6 ft (19.9m) Weight empty: 10,300 lb (4,670 kg) Max cruise speed: 230 mph (370 kph) Ceiling: 24,000 ft (7,300 m) Range: 2,125 miles (3,400 km) Crew: 2 Pax cap: 12
Sky Zephyr Engines: 2 x Pratt & Whitney, 850 hp Pax cap: 8 Speed: 260 mph
L.14-H Super Electra Engines: 2 x Pratt & Whitney Hornet S1E-G radial, 652kW Max take-off weight: : 7938 kg / 17500 lb Empty weight: 4672 kg / 10300 lb Wingspan: 19.96 m / 65 ft 6 in Length: 13.51 m / 44 ft 4 in Height: 3.48 m / 11 ft 5 in Wing area: 51.19 sq.m / 551.00 sq ft Max. speed: 398 km/h / 247 mph Ceiling: 7405 m / 24300 ft Range: 3315 km / 2060 miles
Hudson I Engines: two Wright GR-1820-G102A Cyclone, 1100 hp / 745.2kW Propellers: Hamilton-Standard two-position. Max take-off weight: 7938 kg / 17500 lb Empty weight: 5276 kg / 11632 lb Wingspan: 19.96 m / 65 ft 6 in Length: 13.51 m / 44 ft 4 in Height: 3.61 m / 11 ft 10 in Wing area: 51.19 sq.m / 551.00 sq ft Max. speed: 396 km/h / 246 mph / 214 kt Service Ceiling: 2323 m / 7620 ft Ceiling: 7620 m / 25000 ft Range: 3150 km / 1957 miles / 1703 nm Armament: 4 x 7.7mm machine-guns, 635kg of bombs Crew: 6
Hudson II Engines: two 745.2kW Wright GR-1820-G102A Cyclone Propellers: Hamilton-Standard Hydromatic constant-speed
Hudson III Engines: 2 x 1,200hp / 894kW GR-1820-G205A or R-1820-87 Cyclone Fuel: Aviation Gasoline 100 Octane Wing Centre Section Tanks (x4): 536 Imp Gal / 2,437 lt / USG Propeller: Three bladed Hamilton Standard hydromatic constant speed Propeller diameter: 10′ 6″ (3.20m) Wingspan: 65′ 6″ / 19.69 m Length: 44′ 3.75″ / 13.50 m Wing Area: 551 sq. ft / 51.18 sq. m Height: 10′ 10.5″ / 3.32 m Empty weight: 12,100 lb / 5,488 kg Maximum Takeoff weight: 19,500 lb / 8,845 kg Maximum Speed: 219 knots / 252mph / 406km/h Cruise Speed: 170 knots / 196mph / 315km/h at 8000 ft. Landing speed 72 mph. Service ceiling 24,500 ft Maximum bomb load: 1,600lb (726kg) Armament: 2 x Browning 0.303in machine guns / 500rpg; 1 x optional Vickers 0.303in machine gun / 500 rounds; 2 x optional Vickers 0.303in machine guns / 500rpg; 2 x Browning 0.303in machine guns / 1,000rpg.
Hudson IIIA Engines: 2 x 1,200hp / 894kW GR-1820-G205A Cyclone
Hudson IV Engines: 2 x 1,200hp Pratt & Whitney R-1830-SC3G Twin Wasp radials
Hudson IVA
Hudson V Engines: 2 x 1,200hp Pratt & Whitney R-1830-S3G4G Twin Wasp Propellers: Hamilton-Standard two-position
Hudson VI / A-28 Engines: 2 x 1,200hp Pratt & Whitney R-1830-SC3G Twin Wasp radials
A-28A Engines: Two Pratt & Whitney R-1830-45 Twin Wasp radial engines of 1,000 hp each Span: 65 ft. 6 in. Length: 44 ft. 4 in. Height: 11 ft. 10 in. Max weight: 22,350 lbs. Maximum speed: 280 mph Cruising speed: 224 mph Range: 2,100 statute miles Service ceiling: 27,000 ft. Armament: Four .30-cal. machine guns (two fixed in the nose and two in the turret) plus 1,000 lbs. of bombs Serial numbers: 41-23171 to 41-23222 (RAAF: A16-101 to A16-152)
A-29 Hudson Engines: 2 x Wright R-1820-87 Cyclone 9, 1184 hp / 894kW Length: 44.324 ft / 13.51 m Height: 11.909 ft / 3.63 m Wing span: 65.486 ft / 19.96 m Wing area: 551.009 sq.ft / 51.19 sq.m Max take off weight: 20504.3 lb / 9299.0 kg Weight empty: 12826.5 lb / 5817.0 kg Max. speed: 220 kts / 407 kph Cruising speed: 178 kts / 330 kph Service ceiling: 26493 ft / 8075 m Cruising altitude: 14993 ft / 4570 m Wing load : 37.31 lb/sq.ft / 182.0 kg/sq.m Range: 1347 nm / 2494 km Armament: 5x MG cal.30 (7,62mm ), 726kg / 1,600 lb bomb load,
Lockheed decided to produce a reduced-scale version of the 10 Electra which would accommodate six passengers, a crew of two, and, by retaining the powerplant of the 10 Electra, offer enhanced performance. The resulting aircraft, designated Lockheed 12 Electra Junior, was flown for the first time on 27 June 1936 and a total of 130 were built.
The Model 12 was first introduced with a choice of two powerplants: twin 400-hp Wasp Juniors or twin 420-hp Wright Whirlwinds. The largest engine installed in later years was the 450-hp Pratt & Whitney Wasp Junior; this version of the lightweight Lockheed survived in the greatest numbers. In 1936, the Model 12 had the distinction of being the fastest airplane in its class (commercial twin) produced in the United States.
12a Junior
The majority of production aircraft were designated Lockheed 12-A, but many of the total entered military service. The US Army Air Corps acquired three seven-seat C-40 (later UC-40), 10 five-seat C-40A (later UC-40A) and one experimental C-40B aircraft with fixed tricycle landing gear; the designation C-40D (later UC-40D) was allocated to 10 Lockheed 12-As impressed for wartime service. The US Navy received one seven-seat JO-1, five six-seat JO-2 aircraft (one of which was allocated for US Marine Corps use), and a single XJO-3 with fixed tricycle landing gear which was used for carrier deck-landing trials. The type was used also by the air arms of Argentina, Canada, Cuba and the UK, as well as by the Netherlands East Indies army, this last service being the major military user with a total of 36. Of this number, 16 were specially-developed Model 212 crew trainers, with a forward-firing 7.7mm machine-gun, a similar weapon in a dorsal turret, and under-fuselage racks for up to 363kg of bombs.
One aircraft was acquired by NACA, predecessor of NASA, was used to evaluate a wing de-icing system that utilised hot gases from the engine exhaust.
Australian Sidney Cotton who, under the cover of his position as an executive of the Dufaycolour Company, used his specially modified camera-carrying Lockheed 12-A to take clandestine reconnaissance photographs of German military installations in the three months leading up to the beginning of World War II.
The sole YP-24, delivered to the Army on 29 September 1931, was the first fighter designed under engineer Robert Wood at Lockheed. Initially designated XP-900, the YP-24 was a low-wing monoplane two-seater with retractable landing gear, powered by a Curtiss Conqueror engine. Of composite wood and metal construction, it carried a rear gunner and had a top speed of 344km/h. The fastest fighter in the United States in 1931. The YP-24 was big for a fighter, with a wing span of 13.03m and a maximum take-off weight of 1978kg.
During a test flight on 19 October 1931, the YP-24 experienced a mechanical problem with its landing gear partially lowered. The landing gear could not be made to lower fully and lock into place. The pilot was able to retract the gear and was contemplating a belly landing, but observers were concerned that the low-slung engine radiator would dig in, flipping the heavy aircraft on its back. The pilot was ordered to parachute to safety and the YP-24 was lost. It was to be company finances, not the merits of the design, which doomed the YP-24 to ‘one-off’ status. In 1932, the Lockheed firm would separate from both its founder and Detroit Aircraft Corporation, and would be rescued and re-organized by a new chief executive, Robert Gross. But by then it was too late for the YP-24. The Army ordered five YlP-24s and five further airframes to be built as YA-9 attack bombers, but none was ever completed.
Engine: Curtiss Conqueror Max take-off weight: 1978 kg / 4361 lb Empty weight: 1365 kg / 3009 lb Wingspan: 13.03 m / 42 ft 9 in Length: 8.76 m / 28 ft 9 in Height: 2.49 m / 8 ft 2 in Wing area: 27.13 sq.m / 292.02 sq ft Max. speed: 344 km/h / 214 mph Cruise speed: 290 km/h / 180 mph Ceiling: 8047 m / 26400 ft Range: 895 km / 556 miles Armament: 1 x 12.7mm, 1 x 7.62mm fixed machine-guns, 1 x 7.62mm in the rear Crew: 2
To¬gether with Stearman and a young de¬signer, Hall Hibbard, Gross supervised development of the Lockheed 10 the original Electra. If the project failed, the company would surely collapse. Midway through the development, wind tunnel tests revealed that the plane had insufficient rudder control. Working in a wind tunnel at the University of Michigan, a young graduate student modified the design and added a twin tail. It solved the problem, and Gross, recognizing talent, immediately hired the student. His name was Clarence “Kelly” Johnson.
On 23 February 1934, the Lockheed 10 Electra flew. On its maiden flight, one landing gear remained retracted as the plane approached for a landing, and test pilot Marshall Headle had to bring it in on one wheel. His touchdown and rollout limited the damage to just one wing tip and a propeller.
Providing accommodation for 10 passengers, the Electra was a cantilever low-wing monoplane of all-metal construction, with retractable tailwheel landing gear and a tail unit incorporating twin fins and rudders. Powered by two Pratt & Whitney Wasp Junior SBs.
The prototype was followed by 148 production aircraft. The Electra entered service during 1934, initially with Northwest Airlines, and in the late 1930s was used by eight American operators. By the time that the USA became involved in World War II, however, few remained in national airline service for the rapid growth in air travel had already shown these small-capacity aircraft to be uneconomical. In addition to those built for the home market, Electras were exported to Argentina, Australia, Canada, Chile, Colombia, Japan, New Zealand, Poland, Romania, USSR, UK, Venezuela and Yugoslavia. In 1936 several were purchased by British Airways for use on its European routes, particularly to Scandinavia. Small numbers also saw service in the Spanish Civil War and with the outbreak of World War II the type was impressed for service with the Royal Air Force and Royal Canadian Air Force. Use of the Electra by small civil operators continued after the war, as it was cheap to buy and operate, but few remained in service after the late 1960s. The Electra could carry 10 passengers and two crew at 185 mph on a total of 900 bhp. The two Pratt and Whitney radials used 39 gallons per hour.
Production ceased in 1941.
A model 10E Lockheed Electra vanished along with Amelia Earhart and Fred Noonan in 1937.
Electra 10-A Engines: 2 x Pratt & Whitney R-985-13 Wasp Junior SB radial, 336kW / 450 hp Max take-off weight: 4672 kg / 10300 lb Empty weight: 2927 kg / 6453 lb Wingspan: 16.76 m / 55 ft 0 in Length: 11.76 m / 38 ft 7 in Height: 3.07 m / 10 ft 1 in Wing area: 42.59 sq.m / 458.43 sq ft Max. speed: 325 km/h / 202 mph Max cruise: 165 kt Econ Cruise: 140-145 kt Ceiling: 5915 m / 19400 ft Range: 1305 km / 811 miles Crew: 2 Pax seats: 10
Electra 10B Engine: 2 x Pratt & Whitney R985, 450 hp Pax seats: 10
Seeing, in the latter part of 1930, a potential market for a light transport aircraft, Lockheed began development of the six-passenger Lockheed 9 Orion. This combined a Vega fuselage with the low-wing and landing gear of the Altair, and the NACA cowling introduced on the Air Express, the first being flown in early 1931.
The first Orion (NC960Y) entered service with Bowen Air Lines at Fort Worth, Texas, in May 1931.
The type found use with 12 other American airlines. At least 13 of these aircraft, from various sources, were supplied to the Spanish Republican air force in late 1936, soon after the beginning of the Spanish Civil War. Orion production totalled 35, and the single Altair DL-2A was also converted to Orion configuration.
Lockheed 9C Orion Engine: Wright Cyclone 1820-E, 567 hp Length: 28.051 ft / 8.55 m Height: 9.514 ft / 2.9 m Wingspan: 42.782 ft / 13.04 m Max take off weight: 5402.3 lb / 2450.0 kg Max. speed: 157 kts / 290 km/h Service ceiling: 16732 ft / 5100 m Range: 513 nm / 950 km Crew: 1+4
Lockheed 9D Orion Engine: 1 x Pratt & Whitney Wasp S1D1 radial, 410kW / 450 hp Max take-off weight: 2359 kg / 5201 lb Empty weight: 1651 kg / 3640 lb Wingspan: 13.04 m / 42 ft 9 in Length: 8.64 m / 28 ft 4 in Height: 2.95 m / 9 ft 8 in Wing area: 27.32 sq.m / 294.07 sq ft Cruise speed: 330 km/h / 205 mph Ceiling: 6705 m / 22000 ft Range: 1159 km / 720 miles Undercarriage: retractable. Pax cap: 5.
Developed originally to meet a requirement of Charles Lindbergh for a low-wing monoplane of high performance, the Lockheed 8 Sirius combined what was basically a Vega wooden monocoque fuselage with a new low-set cantilever wing. The fuselage is wood laminated and glued, covered with glued plywood. The wings are plywood covered. Ailerons and tail surfaces are plywood covered.
First flown in November 1929, and then powered by a 336kW Pratt & Whitney Wasp radial engine, the Sirius had non-retractable tailwheel landing gear and two open cockpits in tandem. Before accepting this aircraft, Lindbergh had a sliding canopy installed to enclose the two cockpits. In the following year, before Lindbergh set out on a survey flight for Pan American Airways, a 429kW Wright Cyclone engine and twin-float landing gear were installed. For its final survey flight in 1933, it was powered by a 529kW Wright Cyclone engine.
The success of Lindbergh’s aircraft led to the construction of 13 more by Lockheed, comprising four similar Sirius 8, eight Sirius 8A with enlarged tail surfaces, and a single four-seat Sirius 8C aircraft which had an enclosed cabin for two between the engine and pilot’s cockpit. One Sirius built by the Detroit Aircraft Corporation, with a metal fuselage and Lockheed wooden wing, had the designation DL-2 Lindbergh’s Sirius spanned 13.04m, weighed a maximum of 3220kg, was capable of a maximum of 298km/h, and had a range of 1570km, all in landplane configuration.
Sirius 8
When acquiring his Sirius, Charles Lindbergh had intimated that he might be interested in having retractable landing gear, with a result that the company designed an alternative wing to accept inward-retracting main landing gear units. Although this feature was not adopted by Lindbergh, it became available as a retrofit for Sirius aircraft, first flown on a company-owned Sirius 8A during September 1930. Redesignated Lockheed Altair 8D in this form, the aircraft was loaned to the US Army Air Corps during 1931 and in November of that year, with a new 336kW Pratt & Whitney R-1340-17 engine installed, was acquired by the USAAC under the designation Y1C-25.
Four more aircraft were converted, two Sirius 8As becoming Altair 8D aircraft, the Detroit Aircraft DL-2 being redesignated Altair DL-2A and, most famous of all, one Sirius receiving the designation Sirius 8 Special. This last aircraft was later acquired by Sir Charles Kingsford Smith and, modified to Altair 8D configuration and named Lady Southern Cross, was used by this pilot, with P. G. Taylor as his navigator, to make the first crossing of the Pacific Ocean from Australia to the United States between 20 October and 4 November 1934.
In addition to the conversions, six Altairs were built as new, one of them an Altair DL-2A built by Detroit Aircraft and powered by a 481kW Wright R-1820E Cyclone which was acquired by the US Navy under the designation XRO-1.
Lockheed Sirius Engine: Wright Cyclone, 680 hp at 2100 ft Prop: Hamilton Standard Wingspan: 42 ft 10 in Wing area: 275 sq.ft Airfoil section: Clark Y Length: 27 ft 6 in Height: 9 ft 2 in Empty weight: 2978 lb Gross weight: 4600 lb Gross wt w/pontoon overload: 6000 lb Power loading: 8.83 lb/hp Wing loading: 21.8 lb/sq.ft Top speed: 175 mph Cruise: 145 mph ROC: 1200 fpm Service ceiling: 20,000 ft Radius: 2000 mi Fuel capacity: 225 gal Pontoon fuel capacity: 300 gal
Sirius 8 Wing span: 13.04m Maximum weight: 3220kg Maximum speed: 298km/h Range: 1570km
The success and reliability of the Vega made this aircraft of interest to many airlines, but Western Air Express required some of its own ideas incorporated. With a fuselage, landing gear and tail unit generally similar to the Vega, this aircraft differed primarily by having an increased-span parasol wing, a cabin seating four passengers or carrying 2.83cu.m of mail, with the pilot’s open cockpit moved to the rear of the cabin, as the Lockheed 3 Air Express.
Power was provided as standard by a 306kW Pratt & Whitney Wasp, but at least one was flown with a Wasp engine of 391kW, and some of these engines were enclosed by the NACA-developed low-drag cowling. A total of seven of these aircraft was built, plus one Air Express Special with which Laura Ingalls intended to make a non-stop transatlantic flight in 1931. Western Air Express, which had inspired this development of the Vega, acquired only a single example.
The Lockheed 4 Explorer variant of the Air Express/Vega series with low-set monoplane wing, fixed landing gear and 336kW Pratt & Whitney Wasp, had a wingspan was 14.78m and maximum take-off weight 4086kg. Designed for a non-stop trans-Pacific flight to Japan, only two were built. The first crashed during take-off for the record attempt in July 1929, and the replacement aircraft, with jettisonable landing gear, crashed during trials in September 1929. The theoretical range was 8850km.
The Lockheed 7 Explorer variant was an improved version of the Model 4 with a 336kW Wasp C. The first aircraft crashed during trials in May 1930, and second made some moderately successful flights before being written off
Roscoe Turner had a Lockheed Air Express modified with a parachute in a compartment for his attempts in parachuting an airplane safely to the ground.
Lockheed 3 Air Express Max take-off weight: 1984 kg / 4374 lb Wingspan: 12.95 m / 42 ft 6 in Max. speed: 269 km/h / 167 mph
Lockheed 4 Explorer Engine: 336kW Pratt & Whitney Wasp Wingspan: 14.78m Maximum take-off weight: 4086kg
Jack Northrop, with assistance from Gerard F. Vultee, was working on a project of his own while working for Douglas. It was an airplane design incorporating new structural and aerodynamic thinking that would make his air¬plane the most advanced of its time. Since Douglas was tied up with his World Cruiser project, Northrop took his design to Lockheed, where the airplane became known as the Lockheed Vega, with fully cantilevered wooden wings and finely streamlined monocoque, wooden stressed skin fuselage, made in two halves and glued together.
The two half-shells of plywood had been pressure-formed to shape in a concrete mould. Low-drag landing gear was of fixed tailwheel type (but Vegas were used frequently with floats or skis), enclosed cabin for a pilot and four passengers, and powerplant for the initial version of the Vega, later identified as the Vega 1, was a 168kW Wright J-5 Whirlwind radial engine. The initial aircraft was flown for the first time on 4 July 1927 and was acquired by newspaper-owner George Hearst to compete in the Oakland to Hawaii Dole Race, sponsored by James D. Dole, which began on 16 August 1927. The Vega, by then named Golden Eagle and flown by Jack Forst and Gordon Scott, disappeared without a trace en route.
The unexplained loss of this aircraft did not prohibit further sales. A host of achievements brought fame. These included the first trans-Arctic flight and the first exploratory flight over Antarctica (Wilkins and Eielson in the Vega 1 X3903); the first solo transatlantic flight by a woman from Newfoundland to Ireland (Amelia Earhart in the Vega 5B NC7952); and the first solo round-the-world flight (Wiley Post in the Vega 5B The Winnie Mae). In 1931 Wiley Post flew around the world in 8 days, 15 hours and 51 minutes in a Vega with a jettisonable undercarriage. Wiley Post his navigator, Harold Gatty, and the Winnie Mae left New York on June 23, 1931, flying east. Fourteen stops later, after only eight days, 15 hours and 51 minutes, it was back in New York. The actual flying time was four days, 10 hours, and 8 minutes.
The Vega DL 1 was fitted with a metal fuselage. At least one Vega 5C was sold to the AAF and designated UC 101.
Vega S Special
A “one-off” Vega S Special which was modified for attacks on speed records. The wing was lowered and the angle of attack changed, but equally important was the adoption, for the first time, of the now familiar “bubble” canopy. The inscriptions indicate that NR-496M (c/n. 619) was owned by Crosley Radio Corporation, on loan to the record-breaking aviatrix Ruth Nichols – sponsored by Life Savers Candy.
Vega S Special
When production ended a total of 128 Vegas had been built: 115 by Lockheed, nine by Detroit Aircraft Corporation (of which Lockheed was a division from 1929-31) and four by others.
Vega Engine: One 425 h.p. Pratt & Whitney Wasp. Length 27.5 ft (8.37 m). Wing span 41 ft (12.5 m). Weight empty 2,050 lb (930 kg). Seats: 7. Cruise speed: 135 mph (218 kph). Max speed: 204 mph. Ceiling: 17,250 ft (5,250 m) fully loaded. Range: 900 miles (1,450 km).
Vega 5C (landplane) Engine: 1 x Pratt & Whitney Wasp SC-1 radial, 336kW / 550hp Max take-off weight: 2155 kg / 4751 lb Empty weight: 1163 kg / 2564 lb Wingspan: 12.5 m / 41 ft 0 in Length: 8.38 m / 27 ft 6 in Height: 2.59 m / 8 ft 6 in Wing area: 25.55 sq.m / 275.02 sq ft Max. speed: 298 km/h / 185 mph Ceiling: 5485 m / 18000 ft Range: 885 km / 550 miles
All Aero 