North American Aviation Engineering Test Pilot Louis Wait with a wind tunnel model of the NA-73X. (North American Aviation, Inc.)
28 June 1940: A ¼–scale mahogany model of the North American Aviation NA-73X, prototype of the Royal Air Force Mustang Mk.1, was tested in the Ten-Foot Wind Tunnel at the Guggenheim Aeronautical Laboratory of the California Institute of Technology (GALCIT) in Pasadena, California, from 28 June to 26 July 1940.
The Ten-Foot Tunnel was funded by a $300,000 grant from the Daniel Guggenheim Foundation. Construction of the Laboratory began in 1927 and the wind tunnel became operational in November 1929. A 15 foot (4.572 meter) diameter fan was capable of producing air speeds up to 200 miles per hour (322 kilometers per hour). The first complete scale model airplane to be tested was the Northrop Alpha.
Airships, airplanes, and structures (bridges, buildings) were tested in the tunnel. According to Caltech, the Douglas Aircraft Company used the facility more than any other manufacturer.
During World War II, a staff of sixty worked three shifts, seven days a week. A technician who worked there later said, “We had a tighter schedule than the tightest schedule anyone ever had.”
The wind tunnel’s test equipment was damaged by the Whittier Narrows Earthquake. It was closed in 1997 to be replaced by a new facility.
Model builders working on a scale model wing for use in NACA’s wind tunnels. (NASA)
Amelia Earhart’s Lockheed Electra 10E NR16020 at Darwin, Northern Territory, Australia, 28 June 1937. (Purdue University Libraries, Archives and Special Collections)
28 June 1937: Leg 27. Koepang, Timor, Dutch East Indies to Darwin, Northern Territory, Australia.
“We crossed the Timor Sea from Koepang, on Timor Island, in three hours and twenty-nine minutes against strong head winds. We flew over fleecy clouds at a height of 7,000 feet. . .
Amelia Earhart on the wing of her Electra at Darwin, Northern Territory, Australia, 28 June 1937. (Unattributed)
“The country of this northern coast of Australia is very different from that surrounding Koepang. There jagged mountains rose against the dawn, while here, as far as one could see, were endless trees on an endless plain. The airport is good and very easy to find. We were pounced upon by a doctor as we rolled to a stop, and thereupon were examined thoroughly for tropical diseases. No one could approach us or the airplane until we had passed muster. If this work is done at all it should be thorough, and I approved the methods, although the formalities delayed refueling operations. The customs officials had to clear the Electra as if she were an ocean-going vessel, but that was done with much dispatch. Inasmuch as we had little in the plane but spare parts, fuel and oil, the process was simplified. At Darwin, by the way, we left the parachutes we had carried that far, to be shipped home. A parachute would not help over the Pacific.”
—Amelia Earhart
Amelia Earhart and Fred Noonan at Darwin, Northern Territory, Australia, 28 June 1937. (Purdue University Libraries, Archives and Special Collections)Great Circle route from Koepang, Timor, Dutch East Indies, to Darwin, Northern Territory, Australia, 445 nautical miles (513 statute miles/825 kilometers). (Great Circle Mapper)
Atlantic-Fokker C-2, A.S. 26-202, Bird of Paradise, taking off at Oakland Municipal Airport, California, 7:09 a.m, 28 June 1927. (U.S. Air Force)
28 June 1927: At 7:09 a.m., PDT, 1st Lieutenant Lester J. Maitland and 1st Lieutenant Albert F. Hegenberger, Air Service, United States Army, took off from Oakland Municipal Airport, California, aboard an Atlantic-Fokker C-2, serial number A.S. 26-202, Bird of Paradise. Their destination was Wheeler Field, Honolulu, Territory of Hawaii, 2,407 miles (3,874 kilometers) across the Pacific Ocean.
The Air Service had been planning such a flight for many years. Specialized air navigation equipment had been developed, much of it by Lieutenant Hegenberger, and simulations and practice flights had been carried out.
Atlantic-Fokker C-2 A.S. 26-202, Bird of Paradise, front view. (U.S. Air Force)Atlantic-Fokker C-2, A.S, 26-202, Bird of Paradise, right profile. (U.S. Air Force)
Bird of Paradise was built by the Atlantic Aircraft Co., Teterboro, New Jersey, the American subsidiary of Fokker. Derived from the civil Fokker F.VIIa/3m, a three-engine high-wing passenger transport with fixed landing gear. It had been adopted by the Air Service as a military transport. A.S. 26-202 was modified with a larger wing, increased fuel capacity, and the installation of Hegenberger’s navigation equipment.
It was powered by three 787.26-cubic-inch-displacement (12.901 liter) air-cooled Wright Aeronautical Corporation Model J-5C Whirlwind nine-cylinder radial engines with a compression ratio of 5.1:1. The J-5C was rated at 200 horsepower at 1,800 r.p.m., and 220 horsepower at 2,000 r.p.m. They turned two-bladed Standard adjustable-pitch propellers through direct drive. The Wright J-5C was 2 feet, 10 inches (0.864 meters) long and 3 feet, 9 inches (1.143 meters) in diameter. It weighed 508 pounds (230.4 kilograms).
The C-2 was fueled with 1,134 gallons (4,293 liters) of gasoline and 40 gallons (151 liters) of oil.
Lieutenants Lester J. Maitland and Albert F. Hegenberger are congratulated on their transoceanic flight at Wheeler Field, Hawaii, 29 June 1927. (U.S. Air Force)
Maitland and Hegenberger planned to fly a Great Circle route to Hawaii and to use radio beacons in California and Hawaii to guide them, in addition to celestial navigation. For most of the flight, however, they were not able to receive the radio signals and relied on ded reckoning.
Great Circle route from Oakland International Airport, California, to Wheeler Field, Hawaii, 2,093 nautical miles (2,408 statute miles/3,876 kilometers). (Great Circle Mapper)Captain Alfred Hegenberger in the navigational sighting station of Bird of Paradise. (NASM)Atlantic-Fokker C-2 “Bird of Paradise” interior view, looking forward from navigator compartment. (U.S. Air Force)
After 25 hours, 50 minutes of flight, Bird of Paradise landed at Wheeler Field, 6:29 a.m., local time, 29 June 1927. It had completed the first Transpacific Flight.
For their achievement, both officers were awarded the Distinguished Flying Cross.
Bird of Paradise, Atlantic-Fokker C-2 serial number 26-202, arrives at Wheeler Field, Honolulu, Territory of Hawaii, after a non-stop flight from Oakland, California, 6:29 a.m., 29 June 1927. (U.S. Air Force)
Boeing 747-400 N401PW lifts off the runway at Moses Lake, Washington. (Boeing)
27 June 1988: During flight testing of the first Boeing 747-400 airliner, N401PW, serial number 23719, test pilots James C. Loesch and Howard B. Greene took off from Moses Lake, Washington and climbed to an altitude of 2,000 meters (6,562 feet). The total weight of the airplane was 405,659 kilograms (894,325 pounds). This set a new Fédération Aéronautique Internationale (FAI) World Record for Greatest Mass Carried to a Height of 2,000 Meters.¹
N401PW, the first Boeing 747-400 airliner. (Boeing)
The 747-400 was a major development of the 747 series. It had many structural and electronics improvements over the earlier models, which had debuted 18 years earlier. New systems, such as a “glass cockpit”, flight management computers, and new engines allowed it to be flown with a crew of just two pilots, and the position of Flight Engineer became unnecessary. The most visible features of the –400 are its longer upper deck and the six-foot tall “winglets” at the end of each wing, which improve aerodynamic efficiency be limiting the formation of wing-tip vortices. At the time of its first flight, Boeing had already received orders for 100 747-400s. It would become the most popular version, with 694 aircraft built by the time production came to an end 15 March 2007.
The Boeing 747-400 airliner can carry between 416 and 524 passengers, depending on configuration. It is 231 feet, 10 inches (70.663 meters) long with a wingspan of 211 feet, 5 inches (64.440 meters) and overall height of 63 feet, 8 inches (19.406 meters). Empty weight is 394,100 pounds (178,761 kilograms). Maximum takeoff weight (MTOW) is 875,000 pounds (396,893 kilograms). While the prototype was powered by four Pratt and Whitney PW4056 turbofan engines, production airplanes could be ordered with PW4062, General Electric CF6 or Rolls-Royce RB211 engines, providing thrust ranging from 59,500 to 63,300 pounds. The –400 has a cruise speed of 0.85 Mach (567 miles per hour, 912 kilometers per hour) and maximum speed of 0.92 Mach (614 miles per hour, 988 kilometers hour). Maximum range at maximum payload weight is 8,355 miles (13,446 kilometers).
Northwest Airlines’ Boeing 747-451 N661US on approach to Osaka Kansai International Airport, 11 June 2007. (Photograph courtesy of Dennis Lau)
After the test program was completed, the prototype 747-400 was outfitted for airline service configured as a 747-451. It was operated by Northwest Airlines and Delta Air Lines. It was been re-registered as N661US, and carries the Delta fleet number 6301.
Boeing 747-451 N661US, Delta Air Lines, landing at Tokyo-Narita International Airport, 25 July 2009. (Photograph courtesy of Kazuchika Naya)
N661US flew its last revenue flight 9 September 2015, from Honolulu (HNL) to Atlanta (ATL). It was then withdrawn from service. The first 747-400 is on display at the Delta Flight Museum near Hartsfield-Jackson International Airport, Atlanta, Georgia.
Boeing 747-400 N661US at the Delta Flight Museum. (AIA Georgia)
Aérospatiale AS 350 C Nº. 001, F-WVKH. during a test flight. (Airbus)
27 June 1974: Societe nationale industrielle aérospatiale (SNIAS) test pilot Daniel Bauchart and flight test engineer Bernard Certain took the first prototype Aérospatiale AS 350, F-WVKH, for a 40 minute first flight at at Marignane, France.
The AS 350 C, Nº. 001, was powered by a Lycoming LTS101-600A-1 turboshaft engine rated at 592 shaft horsepower. A second prototype, AS 350 B, F-WTNB, powered by a Turboméca Arriel engine, flew for the first time 14 February 1975.
Initially known internally as the “Business Allouette” after another SNIAS helicopter, the company eventually named the new helicopter Écureuil, which means “squirrel” in English. The name was announced publicly 9 March 1976. Helicopters for the North American market were called the “A-Star.”
Aérospatiale AS 350 C F-WVKH. (Airbus)
The Aérospatiale AS 350 Écureuil is a 6–7 place, single-engine light helicopter, operated by a crew of one or two pilots. Introduced by Aérospatiale in 1978, it remains in production today and is one of the most popular civil helicopters, with more than 5,000 built. The manufacturer is now known as Airbus Helicopters. The current model is the Airbus H125 (previously named the Eurocopter AS 350 B3e)
The Lycoming LTS101-600A engine that powered the AS 350 C prototype and U.S.-production A-Stars is a turboshaft engine with a single stage axial-flow, single stage centrifugal-flow compressor section, and annular combustor, a single stage gas generator turbine and single stage free power turbine. The gas generator section (N1) turned 49,638 r.p.m, 5-minute limit for takeoff, and the power turbine (N2), 6,085 r.p.m. The -600A-2 is 0.786 meters (2 feet, 6.95 inches) long, 0.492 meters (1 foot, 7.37 inches) wide and 0.600 meters (1 foot, 11.62 inches)high. It weighs 115 kilograms (253.5 pounds).
The second prototype, the Turbomeca-powered AS 350 B, F-WTNB. (Airbus)
The AS 350 B3 is a high-performance variant, specially configured for high density altitude operations (“hot and high”). The overall length with rotors turning is 12.94 meters (42 feet, 5.4 inches). The fuselage is 10.93 meters (35 feet, 10.3 inches) long and the cabin is 1.87 meters (6 feet, 1.6 inches) wide. The helicopter’s overall height is 3.14 meters (10 feet, 3.6 inches).
In keeping with standard French practice, the Écureuil/A-Star’s main rotor system turns clockwise as seen from above. (The advancing blade is on the helicopter’s left side.) The composite hingeless three-blade rotor has a diameter of 10.69 meters (35 feet, 0.9 inch). The normal operating range is 385–394 r.p.m. (320–430 r.p.m. in autorotation). A two-bladed tail rotor is mounted on the right side of the tail boom in a pusher configuration. It rotates clockwise, as seen from the helicopter’s left. (The advancing blade is below the axis of rotation.) Its diameter is 1.86 meters (6 feet, 1.2 inches.)
The AS 350 B3 has an empty weight of approximately 1,174 kilograms (2,588 pounds), depending on installed equipment, and maximum gross weight of 2,250 kilograms (4,961 pounds).
AS 350 B3 three-view illustration with dimensions. (Eurocopter)
The AS 350 B3 variant is powered by a single Turboméca Arriel 2B turboshaft engine. The Arriel 2B is a free turbine turboshaft engine which uses an electronic engine control system (EECU). The engine has a two-stage compressor section (single-stage low-pressure axial flow, single-stage high-pressure centrifugal flow); an annular combustion chamber; and two-stage turbine section (single-stage gas generator and single-stage power turbine). The compressor section turns 52,110 r.p.m. at 100% N1; The power turbine, N2, turns 39,095 r.p.m. at 100%. A gear reduction unit reduces the engine’s output shaft speed to 5,990 r.p.m.
The Arriel 2B produces 847 shaft horsepower, but is de-rated to the helicopter’s main transmission limit. Installed, the Arriel 2B is rated at 536 horsepower for cruise; 700 horsepower, Maximum Continuous Power; and 733 horsepower for take off (5 minute limit).
The Arriel 2B is 118.0 centimeters (3 feet, 10.46 inches) long, 50.0 cm (1 foot, 6.69 inches) wide, 62.0 cm (2 feet, 0.41 inches) high. It weighs 134 kilograms (295.4 pounds), dry. The Arriel series engines are now produced by Safran Helicopter Engines.
The AS 350 B3 has a cruise speed of 132 knots (152 miles per hour/245 kilometers per hour) and maximum speed of 155 knots (178 miles per hour/287 kilometers per hour). It carries over four hours of fuel and has a maximum range of 357 nautical miles (411 statute miles/662 kilometers). The maximum allowable altitude is 7,010 meters (23,000 feet).
Turboméca-powered AS 350 B F-WTNB. Note the single horizontal stabilizer. (Airbus)
