19 August 1940: At Mines Field (now known as Los Angeles International Airport), the first North American Aviation B-25 twin-engine medium bomber, serial number 40-2165, took off on its first flight with test pilot Vance Breese at the controls and engineer Roy Ferren in the co-pilot’s position.
The airplane, North American model NA-62, serial number 62-2834, was developed from two earlier designs which had been evaluated by the U.S. Air Corps but rejected, and it was ordered into production without a prototype being built.
The first few B-25s built—sources vary, but 8–10 airplanes—were built with a constant dihedral wing. Testing at Wright Field showed that the airplane had a slight tendency to “Dutch roll” so all B-25s after those were built with a “cranked” wing, with the outer wing panels having very slight dihedral ¹ and giving it the bomber’s characteristic “gull wing” appearance. The two vertical stabilizers were also increased in size.
40-2165 was retained by North American for testing while the next several aircraft were sent to Wright Field.
The B-25 was named Mitchell in honor of early air power advocate Brigadier General Billy Mitchell. A total of 9,984 B-25s, F-10 reconnaissance variants and U.S. Navy and Marine Corps PBJ-1 patrol bombers were built by North American Aviation at Inglewood, California and Kansas City, Kansas. The last one, a TB-25J, remained in service with the U.S. Air Force until 1960.
Twenty-three B-25s were built before the B-25A Mitchell went into production. The B-25 was operated by a crew of five. It was 54 feet, 1 inch (16.485 meters) long with a wingspan of 67 feet, 6.7 inches (20.592 meters) and overall height of 16 feet, 4 inches (4.978 meters). The empty weight was 17,258 pounds (7,828 kilograms) and the maximum gross weight was 28,557 pounds (12,953 kilograms).
The B-25 was powered by two air-cooled, supercharged, 2,603.737-cubic-inch-displacement (42.688 liter) Wright Aeronautical Division Cyclone 14 GR2600B665 (R-2600-9) two-row 14-cylinder radial engines which were rated at 1,500 horsepower at 2,400 r.p.m., and 1,700 horsepower at 2,600 r.p.m. for takeoff. These engines (also commonly called “Twin Cyclone”) drove three-bladed Hamilton Standard Hydromatic variable-pitch propellers through 16:9 gear reduction. The R-2600-9 was 5 feet, 3.1 inches (1.603 meters) long and 4 feet, 6.26 inches (1.378 meters) in diameter. It weighed 1,980 pounds (898 kilograms).
The medium bomber had a maximum speed of 322 miles per hour (518 kilometers per hour) at 15,000 feet (4,572 meters) and a service ceiling of 30,000 feet (9,144 meters). It could carry a 3,000 pound bomb load 2,000 miles (3,219 kilometers).
Defensive armament consisted of three air-cooled Browning M2 .30-caliber aircraft machine guns and one Browning AN-M2 .50-caliber machine gun.
After testing was completed, B-25 40-2165 was retained by North American and modified as a company transport. On 8 January 1945, flown by Edgar A. Stewart, the airplane suffered an engine failure and made a forced landing at Mines Field—the location of its first flight. The prototype B-25 was damaged beyond repair.
¹ The wing center section of the B-25H and B-25J has 4° 38′ 23″ dihedral. The outer sections have 0° 21′ 39″. The wing has 2° 29′ 37″ negative twist.
17 August 1942: Mission No. 1. The United States VIII Bomber Command made its first heavy bomber attack on Nazi-occupied Europe when eighteen Boeing B-17E Flying Fortress four-engine bombers of the 97th Bombardment Group (Heavy), based at RAF Polebrook, Northamptonshire, England, headed for the railroad marshaling yards at Rouen-Sotteville, France. This was the largest and most active railroad yard in northern France.
The group began takeoffs at 1530 hours. It was escorted by several squadrons of Royal Air Force Supermarine Spitfire fighters.
While six B-17s flew along the French coast as a diversion, twelve bombers flew to Rouen and were over the target from 1739 to 1746. From an altitude of 23,000 feet (7,010 meters), they dropped 39,000 pounds (17,690 kilograms) of general purpose bombs.
Accuracy was good. One of the aim points, the locomotive shops, was destroyed by a direct hit. The overall results were moderate.
All of the bombers returned to their base, with the first landing at 1900. Two B-17s had been damaged. American gunners claimed damage to one Luftwaffe airplane.
The raid was commanded by Brigadier General Ira C. Eaker aboard Yankee Doodle, B-17E 41-9023, leading the second flight of six B-17s. The 97th Bombardment Group Commander, Colonel Frank A. Armstrong, Jr., flew as the co-pilot of the lead ship, Butcher Shop, B-17E 41-2578, with pilot Major Paul W. Tibbets, Jr. Major Tibbets was in command of the 97th’s 340th Bombardment Squadron. (He would later command the 509th Composite Group and fly the B-29 Superfortress Enola Gay.)
The Boeing B-17E Flying Fortress was a major redesign. A new aft fuselage was used, incorporating larger vertical and horizontal stabilizers. A tail turret was added. A power-operated gun turret was added at dorsal and ventral positions.
The Boeing B-17E Flying Fortress was a four-engine heavy bomber operated by a flight crew of ten. It was 73 feet, 10 inches (22.504 meters) long with a wingspan of 103 feet, 9-3/8 inches (31.633 meters) and an overall height of 19 feet, 2 inch (5.842 meters). Its empty weight was 32,350 pounds (14,674 kilograms), 40,260 pounds (18,262 kilograms) gross weight, and the maximum takeoff weight was 53,000 pounds (24,040 kilograms).
The B-17E was powered by four air-cooled, supercharged, 1,823.129-cubic-inch-displacement (29.875 liters) Wright Cyclone G666A (R-1820-65) nine-cylinder radial engines with turbochargers, producing 1,200 horsepower at 2,500 r.p.m. for takeoff and 1,000 horsepower at 2,300 r.p.m. at Sea Level. The Cyclones turned three-bladed constant-speed Hamilton-Standard Hydromatic propellers with a diameter of 11 feet, 7 inches (3.835 meters) though a 0.5625:1 gear reduction. The R-1820-65 was 47.59 inches (1.209 meters) long and 55.12 inches (1.400 meters) in diameter. It weighed 1,315 pounds (596 kilograms). 8,422 of these engines were produced by Wright Aeronautical Division and its licensees between February 1940 and August 1942.
The B-17E had a cruise speed of 195 miles per hour (314 kilometers per hour). Its maximum speed was 318 miles per hour (512 kilometers per hour) at 25,000 feet (7,620 meters). The service ceiling was 36,600 feet (11,156 meters).
With a normal fuel load of 2,490 gallons (9,426 liters) the B-17E had a maximum range of 3,300 miles (5,311 kilometers). Carrying a 4,000 pound (1,814 kilogram) bomb load, the range was 2,000 miles (3,219 kilometers).
The B-17E Flying Fortress was armed with one .30-caliber Browning M2 Aircraft Machine Gun and eight Browning AN-M2 .50-caliber machine guns. The .30 was mounted in the nose. Power turrets mounting two .50-caliber guns, each, were located at the dorsal and ventral positions. (The first 112 B-17Es were built with a remotely-operated turret in the belly position, sighted by a periscope. A manned ball turret replaced this.) Two machine guns were in a tail turret, and one on each side at the waist.
The maximum bomb load of the B-17E was 20,800 pounds (9,435 kilograms) over very short distances. Normally, 4,000–6,000 pounds (1,815–2,722 kilograms) were carried. The internal bomb bay could be loaded with a maximum of eight 1,000 pound (454 kilogram) or four 2,000 pound (907 kilogram) bombs.
The B-17 Flying Fortress first flew in 1935, and was in production from 1937 to 1945. 12,731 B-17s were built by Boeing. 512 of the total were B-17Es. The last one was completed 28 May 1942. Production shifted to the further-improved B-17F.
12 August 1930: Frank Monroe Hawks flew from Los Angeles Municipal Airport in California to Curtiss Airport, Valley Stream, Long Island, New York, in a record-breaking 12 hours, 25 minutes, 3 seconds. His airplane was a Travel Air Type R “Mystery Ship” named Texaco No. 13. It carried civil registration NR1313.
One week earlier, 6 August 1930, Hawks had flown across the continent from east to west, in 14 hours, 50 minutes 3 seconds. More favorable winds allowed the Type R to make a faster west-to-east flight.
Hawks’ Texaco No. 13 was the fourth of five specially designed and constructed racing aircraft produced by Travel Air Manufacturing Company of Wichita, Kansas. The company was founded by Walter Beech, Clyde Cessna, and Lloyd Stearman. The “Type R” refers to one of its designers, Herb Rawdon.
The Type R was a low-wing monoplane with a monocoque fuselage built welded tubular steel. The very thin wing was braced by wires. It used spruce spars and ribs. Both fuselage and wings were covered with 1/16-inch mahogany plywood. Attempts to streamline the airplane included a raised profile behind the pilot’s head, “wheel pants,” as well as a NACA-designed engine cowling that provided better engine cooling and caused less aerodynamic drag.
The Travel Air Type R was 20 feet, 2 inches (6.147 meters) long, with a wingspan of 30 feet, 0 inches (9.144 meters) and overall height of 7 feet, 9 inches (2.362 meters). The wing had a chord of 5 feet, 0 inches (1.524 meters), and total area of 125 square feet (11.6 square meters). It had an empty weight of 2,000 pounds (907 kilograms) and gross weight of 3,300 pounds (1,497 kilograms).
The Mystery Ship was powered by an air-cooled, supercharged, 971.930-cubic-inch-displacement (15.927 liter) Wright Aeronautical Division Whirlwind Nine (also known as the J-6-9 or R-975) nine-cylinder radial engine, normally rated at 300 horsepower at 2,000 r.p.m. Various sources state that Hawks’ R-975 had been modified by increasing its compression ratio and supercharger speed, and that it produced 450 horsepower at 2,400 r.p.m. The R-975 was built in both direct drive and geared versions. The two-bladed Standard Steel propeller had a diameter of 8 feet, 0 inches (2.438 meters).
The Mystery Ship’s cruising speed was 200 miles per hour (322 kilometers per hour) at 1,950 r.p.m., and it had a maximum speed of 250 miles per hour (402 kilometers per hour) at Sea Level. It had an initial rate of climb of 3,200 feet per minute (16.26 meters per second). The service ceiling was 30,000 feet (9,144 meters) and the absolute ceiling was 31,000 feet (9,449 meters). The range at cruise speed was 1,000 miles (1,609 kilometers).
One of the fastest airplanes of its time, the Type R set over 200 speed records.
Newspapers called the Type R airplanes “mystery ships” because Beech was very secretive about them. When two of them were flown to the 1929 National Air Races at Cleveland, Ohio, they taxied directly to a hangar and shut off their engines. They were immediately pushed inside. The hangar was kept locked and under guard.
Frank Hawks was an Air Service, United States Army, pilot who served during World War I. He rose to the rank of Captain, and at the time of his record-breaking transcontinental flight, he held a commission as a reserve officer in the Army Air Corps. His flying had made him a popular public figure and he starred in a series of Hollywood movies as “The Mystery Pilot.”
Frank Hawks’ Type R is in the collection of the Museum of Science and Industry, Chicago, Illinois.
1 August 1939: Captains Clarence S. Irvine and Pearl H. Robey, United States Army Air Corps, used the Boeing Y1B-17A Flying Fortress (Model 299F), serial number 37-369, to set a Fédération Aéronautique Internationale (FAI) World Record for Altitude with a 5,000 Kilogram Payload. The bomber climbed to 10,371 meters (34,026 feet) with a payload of 11,023 pounds.¹ ²
On the same day, Irvine and Robey flew the Y1B-17 from Dayton, Ohio to St. Jacob, Illinois, setting an FAI World Record for Speed Over 1,000 Kilometers with a 5,000 Kilogram Payload, averaging 417.46 kilometers per hour (259.40 miles per hour).³
The single Y1B-17A (Boeing Model 299F) was originally ordered as a static test article, but when that was determined to be unnecessary, it was used as an engine test aircraft. It was equipped with four 1,823.129-cubic-inch-displacement (29.875 liter) air-cooled, supercharged, Wright R-1820-51 (Cyclone G59) single-row nine-cylinder radial engines. Moss/General Electric turbo-superchargers were installed, initially on top of the wings, but were moved to the bottom of the engine nacelles.
The supercharged Wright R-1820-39 (Cyclone R-1820-G5) engines of the YB-17s were rated at 805 horsepower at 2,100 r.p.m., at Sea Level, 775 horsepower at 14,000 feet (4,267 meters), and 930 horsepower at 2,200 r.p.m., for take off. By contrast, the YB-17A’s R-1820-51 engines were rated at 800 horsepower at 2,100 r.p.m. at Sea Level, and 1,000 horsepower at 2,200 r.p.m. for take off. But the turbochargers allowed the engines to maintain their Sea Level power rating all the way to 25,000 feet (7,620 meters). Both the -39 and -51 engine had a 16:11 propeller gear reduction ratio. The R-1820-51 was 3 feet, 9.06 inches (1.145 meters) long, 4 feet, 6.12 inches (1.375 meters) in diameter, and weighed 1,200.50 pounds (544.54 kilograms). 259 were produced by Wright between September 1937 and February 1940.
The turbo-superchargers installed on the YB-17A greatly improved the performance of the bomber, giving it a 55 mile per hour (89 kilometer per hour) increase in speed over the supercharged YB-17s, and increasing the bomber’s service ceiling by 7,000 feet (2,132 meters). The turbo-superchargers worked so well that they were standard on all following B-17 production models.
The Boeing Y1B-17A was 68 feet, 9 inches (20.955 meters) long with a wingspan of 103 feet, 9–3/8 inches (31.633 meters) and height of 14 feet, 11–5/16 inches (4.363 meters). Its empty weight was 26,520 pounds (12,029 kilograms). The maximum gross weight was 45,650 pounds (20,707 kilograms)
The Model 299F had a cruise speed of 230 miles per hour (370 kilometers per hour), a maximum speed of 271 miles per hour (436 kilometers per hour) at Sea Level and 295 miles per hour (475 kilometers per hour) at 25,000 feet (7,620 meters). The service ceiling was 38,000 feet (11,582 meters). The maximum range was 3,600 miles (5,794 kilometers). Carrying a 4,000 pound (1,814 kilogram) load of bombs, the range was 2,400 miles (3,862 kilometers).
The Y1B-17A could carry eight 600 pound (272 kilogram) bombs in an internal bomb bay. Defensive armament consisted of five .30-caliber machine guns.
Following the engine tests, 37-369 was re-designated B-17A.
¹ FAI Record File Number 8318
² This record-setting flight was dramatized in the motion picture “Test Pilot,” (1938, Metro-Goldwyn-Mayer) with Clark Gable, Spencer Tracy and Myrna Loy. This movie is now 80 years old and has a melodramatic plot, but is well worth seeing for aviation history enthusiasts.
10–14 July 1938: Howard Robard Hughes, Jr., along with a crew of four, departed Floyd Bennett Field, Brooklyn, New York, on a flight to circle the Northern Hemisphere. His airplane was a Lockheed Super Electra Special, Model 14-N2, registered NX18973. Aboard were Harry P. McLean Connor, co-pilot and navigator; 1st Lieutenant Thomas L. Thurlow, United States Army Air Corps, navigator; Richard R. Stoddart, a field engineer for the National Broadcasting Company (NBC), radio operator; Edward Lund, flight engineer. Lieutenant Thurlow was the Air Corps’ expert on aerial navigation. Stoddart was an expert in radio engineering. Thurlow, Stoddart and Lund were also rated pilots.
Before they took off from Floyd Bennett Field, the Lockheed was christened New York World’s Fair 1939, in keeping with an agreement that Hughes had made with Grover Whalen and the fair’s organizers.
Howard Hughes and his crew departed Floyd Bennett Field at 7:19:10 p.m. on 10 July. The route of the flight was from Floyd Bennett Field to Le Bourget Aerodrome, Paris, France, a distance of 3,641 miles (5,860 kilometers), flown in an elapsed time of 16 hours, 38 minutes; Moscow, Russia, USSR, 1,640 miles (2,639 kilometers), 7:51; Omsk, Siberia, 1,400 miles (2,253 kilometers), 7:27; Yakutsk, Yakut ASSR, 2,158 miles (3,473 kilometers), 10:31; Fairbanks, Alaska, 2,457 miles (3,954 kilometers), 12:17; Minneapolis, Minnesota, 2,441 miles (3,928 kilometers), 12:02; and back to Floyd Bennett Field, 1,054 miles (1,696 kilometers) 4:26.
They arrived at Floyd Bennett Field at 2:34 p.m., 14 July. The distance flown was approximately 14,800 miles (23,818 kilometers) (sources differ). The total duration was 91 hours, 14 minutes, 10 seconds. The actual flight time was 71 hours, 11 minutes, 10 seconds. Average speed for the flight was 206.1 miles per hour (331.7 kilometers per hour).
The international organization for flight records, the Fédération Aéronautique Internationale, requires that a circumnavigation cross all meridians in one direction and be at least the length of the Tropic of Cancer, 22,858.729 miles (36,787.559 kilometers). Howard Hughes’ “around the world flight” circled the Northern Hemisphere and was at least 8,058 miles (12,968 kilometers) short of the required distance, so no official record was set. (The same is true of Wiley H. Post’s two earlier “around the world” flights which used a similar route.)
The National Aeronautic Association awarded the Aero Club Trophy (after 1944, known as the Robert J. Collier Trophy, or simply, The Collier Trophy) to Howard Hughes and his associates, “For their epoch making round the world flight in 91 hours and 14 minutes.” The Collier is an annual award, “. . . for the greatest achievement in aeronautics or astronautics in America, with respect to improving the performance, efficiency, and safety of air or space vehicles, the value of which has been thoroughly demonstrated by actual use during the preceding year.”
The Lockheed Super Electra 14-N2, serial number 1419, was offered to Hughes by the Lockheed Aircraft Company, Burbank, California, at no cost.
Company officials believed that publicity generated by an around-the-world flight would justify the expense. The airplane underwent modification for two months at the Burbank factory. The Curtiss-Wright Corporation provided new engines. Fuel capacity was increased to 1,844 gallons (6,980.3 liters). Three radio systems were installed.
The Lockheed Model 14 Super Electra was an all-metal, twin-engine, low-wing monoplane with retractable landing gear, designed as a medium-sized airliner. It was flown by two pilots and could carry up to 12 passengers. Based on aerodynamic studies carried out by Clarence L. “Kelly” Johnson on the earlier Model 10 Electra, the airplane was configured with an “H-tail”, with vertical fins and rudders placed at the ends of the horizontal stabilizer. This was a characteristic design feature for Lockheed aircraft through the 1950s.
The Model 14 was 44 feet, 4 inches (13.513 meters) long with a wingspan of 65 feet, 6 inches (19.964 meters) and overall height of 11 feet, 5 inches (3.480 meters). Hughes’ Model 14-N2 Special differed, but a Model 14-WF-62 airliner version had an empty weight of 10,750 pounds (4,876 kilograms), gross weight of 15,650 pounds (7,098 kilograms) and maximum takeoff weight of 17,500 pounds (7,938 kilograms). The airliner had maximum speed of 250 miles per hour (402 kilometers per hour) and a service ceiling of 24,500 feet (7,468 meters).
NX18973 was powered by two air-cooled, supercharged, 1,823.129-cubic-inch-displacement (29.875 liter) Wright Aeronautical Division Cyclone GR-1820-G102 nine-cylinder radial engines with a normal power rating of 900 horsepower at 2,200 r.p.m., and 1,100 horsepower at 2,200 r.p.m for take-off. The engines had a compression ratio of 6.7:1 and required 91-octane gasoline. They turned three-bladed Hamilton Standard constant-speed propellers through a 0.6875:1 gear reduction. The GR-1820-102 was 4 feet, 0.12 inches (1.222 meters) long, 4 feet, 7.10 inches (1.400 meters) in diameter, and weighed 1,275 pounds (578 kilograms).
Representative performance figures are maximum speed of 250 miles per hour (402 kilometers per hour) and a service ceiling of 24,500 feet (7,468 meters). NX19783 had an estimated maximum range of 4,500 miles (7,242 kilometers).
Following Hughes’ flight, NX18973 was returned to Lockheed. The manufacturer then sold the Super Electra to the Royal Canadian Air Force. It was assigned fuselage identification AX688. (A militarized version of the Super Electra was produced as the Hudson light bomber.)
On 10 November 1940, the Super Electra took off from Nairobi, Kenya, on a transcontinental ferry flight to from South Africa to Egypt. There were high winds and it was raining. After climbing to 500 feet (152 meters) AGL, the Lockheed banked to the left. It stalled, entered a spin and crashed. The wreck caught fire. All persons on board were killed.