Vertol YCH-1B-BV 59-4983 hovers in ground effect. (Boeing Vertol)
21 September 1961: Boeing Vertol YCH-1B-BV, serial number 59-4983, a twin-turboshaft, tandem-rotor heavy lift helicopter, flown by test pilot Leonard Joseph (“Len”) LaVassar, made its first flight at Morton Grove, Pennsylvania. This aircraft was the number two prototype. (The first aircraft, 52-4982, had been damaged 12 July 1961 when the rotors went out of phase during ground testing. It was repaired but never flew.) In 1962, the YCH-1B was was redesignated YCH-47A.
The YCH-1B fuselage was 51 feet, 0 inches (15.545 meters) long and had a maximum width of 12 feet, 5 inches (3.785 meters). The helicopter’s overall length, with rotors turning, was 98 feet, 3.25 inches (29.953 meters), and its maximum height (to the tip of the uppermost blade) was 18 feet, 6.6 inches (5.654 meters). Empty weight of the production CH-47A is approximately 25,500 pounds.
The counter-rotating fully-articulated three-bladed rotors each had a diameter of 59 feet, 1.25 inches (18.015 meters). The forward rotor turned counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right side.) The rear rotor turns the opposite direction. They rotate at 215 r.p.m.
Boeing Vertol YCH-1B-BV 59-04983
The prototypes were powered by two Lycoming LTC4B-3 (T55-L-5) turboshaft engines. These were free-turbine engines using a 7-stage axial-flow, 1-stage centrifugal-flow compressor section with a single-stage high-pressure turbine and two-stage low-pressure power turbine. The T55-L-5 was rated at 1,870 shaft horsepower at 14,430 r.p.m. N2. It was 3 feet, 8.1 inches (1.120 meters) long and weighed 560 pounds (254 kilograms).
The helicopter had a maximum speed of 153 knots (176 miles per hour/283 kilometers per hour) at Sea Level. Its hover ceiling, out of ground effect (HOGE), was 11,650 feet (3,551 meters), and in ground effect (HIGE), 14,500 feet (4,420 meters). The helicopter’s service ceiling was 18,600 feet (5,669 meters).
The Chinook prototypes were painted white and orange. This is the third YCH-1B, 59-4984. (Boeing Vertol)
The Chinook remains in production as the CH-47F Block I and MH-47G, and is used by the military services of several nations. Boeing is continuing development of the Block II variant.
A Boeing XB-29 takes off from Boeing Field, Seattle, Washington. (SDASM)Edmund T. (“Eddie”) Allen
21 September 1942: At Boeing Field, Seattle, Washington, the Boeing Model 345, the first of three XB-29 prototypes, Air Corps serial number 41-002, took off on its first flight.
Edmund T. “Eddie” Allen, Director of Aerodynamics and Flight Research, was in command, with Al Reed, Chief of Flight Test and Chief Test Pilot, as co-pilot. They climbed to 6,000 feet (1,829 meters) and began testing the XB-29’s stability and control, control power and response, and stall characteristics.
The flight was uneventful. Landing after 1 hour, 15 minutes, Allen is supposed to have said, “She flew!”
Eddie Allen lean’s out of a cockpit window following the first taxi test of the XB-29. (Boeing)
The XB-29 was 98 feet, 2 inches (29.921 meters) long with a wing span of 141 feet, 3 inches (43.053 meters), and 27 feet, 9 inches (8.458 meters) high to the top of its vertical fin. The prototype bomber had a gross weight of 105,000 pounds (47,627 kilograms).
Boeing XB-29-BO, 41-002, the first of three prototypes. (U.S. Air Force)
The prototype bomber was powered by four air-cooled, supercharged and fuel-injected 3,347.662-cubic-inch-displacement (54.858 liter) Wright Aeronautical Division Duplex-Cyclone 670C18H1 (R-3350-13) twin-row 18-cylinder radial engines with a compression ratio of 6.85:1. The R-3350-13 was rated at 2,000 horsepower at 2,400 r.p.m., and 2,200 horsepower at 2,800 r.p.m. for takeoff, burning 100-octane gasoline. These engines drove 17-foot-diameter (5.182 meters) three-bladed Hamilton Standard constant-speed propellers through a gear reduction of 0.35:1. The R-3350-13 was 76.26 inches (1.937 meters) long, 55.78 inches (1.417 meters) in diameter, and weighed 2,668 pounds (1,210 kilograms). Wright built 50 of these engines.
Boeing XB-29 41-002. (SDASM)
The XB-29 had a maximum speed of 368 miles per hour (592 kilometers per hour) and cruised at 255 miles per hour (410 kilometers per hour). Its service ceiling was 32,100 feet (9,784 meters).
The airplane was designed to carry 20,000 pounds (9,072 kilograms) of bombs. Though the prototypes were unarmed, the production B-29s were defended by 10 Browning AN-M2 .50-caliber machine guns in four remotely-operated power turrets, with 2 more .50-caliber machine guns and a single AN-M2 20mm autocannon in the tail.
Boeing XB-29 41-002. (SDASM)
The B-29 Superfortress was the most technologically advanced—and complex—aircraft of the War. It required the manufacturing capabilities of the entire nation to produce. Over 1,400,000 engineering man-hours had been required to design the prototypes.
The B-29 was manufactured by Boeing at Seattle and Renton, Washington, and at Wichita, Kansas; by the Glenn L. Martin Company at Omaha, Nebraska; and by Bell Aircraft Corporation, Marietta, Georgia. There were three XB-29 prototypes, 14 YB-29 pre-production test aircraft, 2,513 B-29, 1,119 B-29A, and 311 B-29B Superfortress aircraft. The bomber served during World War II and the Korean War and continued in active U.S. service until 1960.
The first prototype, 41-002, was scrapped in 1948.
Boeing B-29A-30-BN Superfortress 42-94106, circa 1945. (U.S. Air Force)
Geoffrey de Havilland, Jr., exits the cockpit of one of the company’s jet aircraft. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)
20 September 1943: Geoffrey Raoul de Havilland, Jr., chief test pilot of the de Havilland Aircraft Co., Ltd., made the first flight in the prototype DH.100, LZ548/G, at Hatfield, Hertfordshire. (The “/G” in the identification indicated that the aircraft was to be guarded at all times.) Assigned the code name Spider Crab, the production DH.100 would be better known as the de Havilland Vampire.
The flight lasted approximately 30 minutes and the airplane exceeded 400 miles per hour (644 kilometers per hour). De Havilland reported that the prototype was trimmed with the left wing down, had overly sensitive ailerons and demonstrated instability in yaw with rudder applications.
This oscillation in the yaw axis—called “snaking”—was determined to be a result of the overly effective vertical fins. After wind tunnel and flight testing, it was decided to reduce the fins’ area, resulting in the flat top configuration seen in bottom photograph.
Right front view of the first prototype de Havilland DH.100, LZ548/G, prior to its first flight. The letter “P” in a circle next to the RAF insignia identifies the airplane as a prototype. The “/G” in the identification number indicates that a guard is required at all times. (De Havilland Aircraft Co., Ltd.)
The DH.100 was a single-seat, single-engine fighter powered by a turbojet engine. The twin tail boom configuration of the airplane was intended to allow a short exhaust tract for the engine, reducing power loss in the early jet engines available at the time.
Right side view of the de Havilland DH.100 Spider Crab LZ548/G.
LZ548/G was originally powered by a Halford H.1 turbojet which produced 2,300 pounds of thrust (10.231 kilonewtons) at 9,300 r.p.m. This engine was produced by de Havilland and named Goblin.
The Goblin is a linear descendant of the early Whittle units. It comprises a single-sided centrifugal compressor delivering air to sixteen combustion chambers grouped symmetrically around the axis of the unit and leading to the nozzle of the single-stage axial turbine which drives the compressor. Compressor impeller and turbine rotor are coupled by a tubular shaft to form a single rotating assembly which is mounted on only two ball bearings. The maximum diameters of the engine, around the compressor casing, is 50in., [1.27 meters] and with a jet pipe of minimum length fitted the overall length is about 8ft. [2.438 meters] Equipped with a jet pipe and all the necessary engine auxiliaries the dry weight of the complete unit is 1,500 lb. [680 kilograms] Fuel consumption is at the rate of 1.23 lb. / hr. per lb. thrust.
—FLIGHT and AIRCRAFT ENGINEER, No. 1923. Vol. XLVIII. Thursday, 1 November 1945 at Page 472, Column 2
The Vampire entered service with the Royal Air Force in 1945 and remained a front-line fighter until 1953. 3,268 DH.100s were built.
Right rear quarter view of the prototype de Havilland DH.100, LZ548/G. In this photograph, the airplane’s vertical fins have been squared off. This would be a feature of the production Vampire F.1.
The first of the three prototype Vampires, LZ548, crashed after takeoff from Hatfield, 23 July 1945, due to a fuel pump failure. Geoffrey Pike, the pilot, was not injured.
The first prototype V-24. The stub wings are nearly horizontal. (Image from “Russian Gunship Helicopters,” by Yefim Gordon, Pen and Sword Aviation 2013, at Page 6)Алфёров Герман Витальевич
19 September 1969: After four days of testing in a tethered hover, OKB Mil Design Bureau test pilot Herman V. Alferov made the first free flight of the prototype Mil Mi-24 attack helicopter, V-24.
Designed by a team led by Chief Project Engineer V. A. Kuznetsov, the Mi-24 used the drive train of the Mil Mi-8 Hip-B/C transport and Mi-14 Haze-A anti-submarine helicopters. It had a five-blade main rotor. a three-blade tail rotor and was equipped with retractable tricycle landing gear.
The Mi-24 (named “Hind” by NATO forces) was operated by a pilot and a weapons system operator seated in tandem configuration, with the pilot slightly offset to the left. The gunner is in the forward position. It differed from the American Bell AH-1G Cobra attack helicopter in that it could carry 8 troops or 1,500 pounds (680 kilograms) of cargo in a center fuselage compartment.
Prototype V-24 during test flight. (Unattributed)
The Mi-24 is 17.5 meters (57 feet, 5 inches) long, 6.5 meters (21 feet 4 inches) high, with a main rotor diameter of 17.3 meters (56 feet, 9 inches). As is standard practice with Soviet helicopters, the five-blade main rotor turns clockwise as seen from above. (The advancing blade is on the left.) The tail rotor diameter is 3.9 meters (12 feet, 9½ inches).
The entire fuselage is tilted 2° 30′ (and thus, the transmission, mast and main rotor) to the right to counteract the rotor system’s translating tendency, and helps with high-speed stability.
In early versions, the tail rotor was mounted on the right side in pusher configuration and rotated counter-clockwise as seen from the left. (The advancing blade is above the axis of rotation.) Because of poor handling conditions, the tail rotor was changed to the left side in tractor configuration, with the advancing blade below the hub.
The helicopter’s empty weight is 8,500 kilograms (18,739 pounds) and loaded weight is 12,000 kilograms (26,455 pounds).
Power is supplied by two Isotov TV3-117 turboshaft engines rated at 1,700 shaft horsepower, or 2,200 horsepower for takeoff or one engine inoperative emergency operation.
The Mi-24 has a maximum speed of 335 kilometers per hour (208 miles per hour) and range of 450 kilometers (280 miles). The service ceiling is 4,500 meters (14,764 feet).
Armament consists of a turret-mounted Gryazev-Shipunov GSh-23 23mm cannon with 450 rounds of ammunition. Air-to-air and air-to-ground missiles are carried on pylons mounted under the helicopter’s stub wings.
More than 5,200 Mi-24 attack helicopters have been built, many of them exported. It is estimated that the cost of an individual helicopter is $32,500,000.
“Red 77,” the prototype Mil Mi-24A helicopter. Note the anhedral of the wings. (Russian Helicopters photo)
Herman V. Alferov (Алфёров Герман Витальевич)—also known as G.V. Alferov or German V. Alferov—was born at Moscow, Russia, U.S.S.R., 11 April 1934. He graduated from the 3rd Moscow Flying Club in 1950, and from 1952 to 1954 was a flight instructor at the Central Aeroclub Chkalov. In 1954, He graduated from the Voluntary Society of Assistance to the Air Force (DOSAAF) central flight technical school at Saransk in the Mordovian Autonomous Oblast.
Alferov was employed as a test pilot at OKB Mil in Moscow from 1954 until 1982, and remained with the flight test center until 1992. He participated in setting 11 Fédération Aéronautique Internationale (FAI) world helicopter records, and was named an Honored Test Pilot of the Soviet Union, 16 November 1973. In 1977, he was awarded the Order of the October Revolution, twice received the Order of the Red Banner of Labor, and twice the Order of the Red Star.
Herman V. Alferov died 19 January 2012.
Herman V. Alferov with a Mil Mi-4 helicopter, circa 1960. (Unattributed)
Lieutenant Ellis Dent Shannon, Air Corps, United States Army
18 September 1948: The first delta-winged aircraft took flight for the first time when Consolidated-Vultee Aircraft Corporation test pilot Ellis D. “Sam” Shannon lifted off from Muroc Dry Lake with the prototype delta-wing XF-92A, serial number 46-682. For the next 18 minutes he familiarized himself with the new aircraft type, before landing back on the lake bed.
The Convair XF-92A on Muroc Dry Lake. (U.S. Air Force)
Later, with Captain Chuck Yeager flying, the XF-92A reached Mach 1.05. Yeager found that the airplane’s delta wing made it nearly impossible to stall, even with a 45° angle of attack. He was able to land the airplane at nearly 100 miles per hour slower than the designers had predicted.
The XF-92A was a difficult airplane to fly. NACA test pilot Scott Crossfield commented, “Nobody wanted to fly the XF-92. There was no lineup of pilots for the airplane. It was a miserable flying beast.” Scotty made 25 flights in the experimental delta-winged aircraft. On its last flight, 14 October 1953, the airplane’s nose gear collapsed after landing. The XF-92A was damaged and never flew again.
Convair XF-92A 46-682 on Muroc Dry Lake, 1948. (U.S. Air Force)
The XF-92A (Consolidated-Vultee Model 7-002) was a single-place, single-engine prototype fighter. The airplane was 42 feet, 6 inches (12.954 meters) long with a wingspan of 31 feet, 4 inches (9.550 meters) and overall height of 17 feet, 9 inches (5.410 meters). It had an empty weight of 9,078 pounds (4,118 kilograms) and gross weight of 14,608 pounds (6,626 kilograms).
The prototype was originally powered by an Allison J33-A-21 turbojet engine with a single-stage centrifugal flow compressor and single-stage turbine. It produced 4,250 pounds of thrust at 11,500 r.p.m. at Sea Level. The engine was 8 feet, 6.9 inches (2.614 meters) long, 4 feet, 2.5 inches (1.283 meters) in diameter, and weighed 1,850 pounds (839 kilograms). This was later replaced by a more powerful J33-A-29 (7,500 pounds thrust).
The XF-92A touches down on Muroc Dry Lake, 1948. (San Diego Air and Space Museum Archives)
The XF-92A had a maximum speed of 718 miles per hour (1,156 kilometers per hour) and a service ceiling of 50,750 feet (15,469 meters).
The XF-92A was not put into production. It did appear in several motion pictures, including “Toward The Unknown” (one of my favorites) and “Jet Pilot.” It is in the collection of the National Museum of the United States Air Force. This was the first of several Convair delta-winged aircraft, including the F2Y Sea Dart, F-102A Delta Dagger and F-106A Delta Dart supersonic interceptors, and the B-58A Hustler four-engine Mach 2+ strategic bomber.
Convair XF-92A. (NACA High Speed Flight Station)
Consolidated-Vultee XF-92A 46-682 is displayed at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio.
The flight test program of the XF-92A came to an ignominious conclusion on 14 October 1953. (San Diego Air and Space Museum Archives)
Ellis Dent Shannon was born at Andalusia, Alabama, 7 February 1908. He was the third of five children of John William and Lucy Ellen Barnes Shannon.
He was commissioned as a second lieutenant the Alabama National Guard (Troop C, 55th Machine Gun Squadron, Cavalry) 21 May 1926. He transferred to the U.S. Army Air Corps in 1929. In 1930, he was stationed at Brooks Army Airfield, Texas.
In 1932 Shannon was employed was assigned as a flight instructor and an advisor to the government of China.
On 24 December 1932, Shannon married Miss Martha Elizabeth Reid at Shanghai, China. They had son, Ellis Reid Shannon, born at Shanghai, 24 August 1934, and a daughter, Ann N. Shannon, born at Baltimore, Maryland, in 1940.
Shannon and his family returned to the United States in 1935 aboard SS Bremen, arriving at New York.
He was employed by the Glenn L. Martin Co., at Baltimore, Maryland, in 1936 as a test and demonstration pilot. He travel throughout Latin America for the company, demonstrating the company’s aircraft. As a test pilot he flew the Martin Model 187 Baltimore, the B-26 Marauder, PBM Mariner and the Martin JRM Mars.
In February 1943, Shannon started working as a Chief of Flight Research for the Consolidated Aircraft Company at San Diego, California. While there, made the first flights of the Consolidated XB-24K, a variant of the Liberator bomber with a single vertical tail fin; the XR2Y-1, a prototype commercial airliner based on the B-24 Liberator bomber; the XB-46 jet-powered medium bomber; the XP5Y-1 Tradewind, a large flying boat powered by four-turboprop-engines; the Convair 340 Metropolitan airliner; and the XF2Y Sea Dart, a delta-winged seaplane powered by two turbojet engines. Shannon also participated in the flight test program of the YF-102A Delta Dart.
After retiring from Convair in 1956, Ellis and Martha Shannon remained in the San Diego area. Ellis Dent Shannon died at San Diego, California, 8 April 1982 at the age of 74 years.
Ellis Dent Shannon, Convair test pilot, circa 1953. (Photograph courtesy of Neil Corbett, Test and Research Pilots, Flight Test Engineers)
