2 August 1909: The United States Army Signal Corps purchased a Wright Flyer for $30,000. It became the first aircraft in the United States’ military inventory and was designated Signal Corps Airplane No. 1. The airplane was used to train Signal Corps pilots at Fort San Antonio, Texas. It was crashed and rebuilt several times. After just two years’ service, the airplane was retired. The Army donated Airplane No. 1 to the Smithsonian Institution.
During test flights that were conducted prior to acceptance by the Army, Orville Wright with Lieutenant Benjamin D. Fulois as a passenger (he was chosen because of his size and his ability to read maps) the Flyer achieved a two-way average 42.583 miles per hour (68.531 kilometers per hour), over a 5 mile (8.05 kilometers) course. The Signal Corps specification allowed a bonus of $2,500 per full mile per hour above 40 miles per hour. This increased the purchase price of the airplane from $25,000 to $30,000. The Army also required the airplane to be able to remain airborne for a minimum of one hour. Wright demonstrated its endurance at 1 hour, 12 minutes, 40 seconds.
The 1909 Military Flyer is a one-of-a-kind variant of the Wright Brothers’ Model A which was produced from 1907 to 1909. The airplane has shorter wings than the standard Model A, and slightly longer propeller blades which are turned at a different r.p.m. These changes were made to increase the Flyer’s speed through the air. The engine had been salvaged from the 1908 Model A which crashed at Fort Myer in 1908, severely injuring Orville Wright and killing Lieutenant Thomas E. Selfridge.
The Military Flyer is a two-place, single-engine biplane built of a wooden framework braced with wires. The wings, rudders and elevators are covered with muslin. The elevators are placed forward in canard configuration with rudders aft. Roll control was by the Wright Brothers’ patented wing-warping system.
As originally built (it was repaired and slightly modified during its two years in service) the airplane was 28 feet, 11 inches (8.814 meters) long with a wingspan of 36 feet, 6 inches (11.125 meters) and height of 8 feet, 1 inch (2.464 meters). The wings have a chord of 5 feet, 10 inches (1.778 meters) and vertical separation of 5 feet (1.524 meters). The lower wing has 2 feet, 3 inches (0.686 meter) of ground clearance. The elevators have a span of 15 feet, 5 inches (4.699 meters), a chord of 3 feet (0.914 meter) and vertical spacing of 3 feet (0.914 meter). The parallel rudders are 4 feet, 8½ inches (1.435 meters) tall with a chord of 1 foot, 8 inches (0.508 meter). Their lateral separation is also 1 foot, 8 inches (0.508 meter). The rudder pivot point is 15 feet, 11 inches (4.851 meters) aft of the wings’ leading edge. The airplane had an empty weight of 740 pounds (335.7 kilograms).
The Military Flyer was powered by a single water-cooled, fuel-injected, 240.528 cubic-inch-displacement (3.942 liter) Wright vertical overhead-valve inline four-cylinder gasoline engine with 2 valves per cylinder and a compression ratio of 4.165:1. It produced 32 horsepower at 1,310 r.p.m. During three years of production (1908–1911) Wright “4-40” engines were built that operated from 1,325 to 1,500 r.p.m. Power output ranged from 28 to 40 horsepower. These engines weighed from 160 to 180 pounds (72.6–81.6 kilograms).
Two 8 foot, 6 inch (2.591 meter) diameter two-bladed counter-rotating propellers,are mounted behind the wings in pusher configuration. Driven by a chain drive, they turned 425 r.p.m.
The Military Flyer could fly 42 miles per hour (67.6 kilometers per hour) and had endurance of one hour.
Early army officers who trained with Signal Corps Airplane No. 1 included Lieutenants Benjamin D. Fulois, Frank P. Lahm and Frederic E. Humphreys.
The unrestored Wright 1909 Military Flyer is in the collection of the Smithsonian Institution, displayed at the National Mall. A reproduction of the airplane is at the National Museum of the United States Air Force.
© 2018, Bryan R. Swopes
12 July 1957: President Dwight D. Eisenhower was the first United States president to fly in a helicopter when a U.S. Air Force H-13J-BF Sioux, serial number 57-2729 (c/n 1576), flown by Major Joseph E. Barrett, USAF, departed the White House lawn for Camp David, the presidential retreat in the Catoctin Mountains of Maryland. Also on board was a U.S. Secret Service special agent. A second H-13J, 57-2728 (c/n 1575), followed, carrying President Eisenhower’s personal physician and a second Secret Service agent.
The helicopter was intended to rapidly move the president from the White House to Andrews Air Force Base where his Lockheed VC-121E Constellation, Columbine III, would be standing by, or to other secure facilities in case of an emergency.
Major Barrett had been selected because of his extensive experience as a combat pilot. During World War II, he had flown the B-17 Flying Fortress four-engine heavy bomber. During the Korean War, Barrett had carried out a helicopter rescue 70 miles (113 kilometers) behind enemy lines, for which he was awarded the Silver Star.
The two helicopters were manufactured by the Bell Helicopter Company at Fort Worth, Texas, and delivered to the Air Force at Wright-Patterson Air Force Base on 29 March 1957. The presidential H-13Js were nearly identical to the commercial Bell Model 47J Ranger. The H-13J differed from the civil Model 47J by the substitution of main rotor blades of all-metal construction in place of the standard laminated wood blades.
Capable of carrying a pilot and up to three passengers, the Ranger was constructed with an enclosed cabin built on a tubular steel framework with all-metal semi-monocoque tail boom. The main rotor diameter was 37 feet, 2.00 inches (11.328 meters) and tail rotor diameter was 5 feet, 10.13 inches (1.781 meters), which gave the helicopter an overall length of 43 feet, 3¾ inches (13.185 meters) with rotors turning. The height (to the top of the centrifugal flapping restraints) was 9 feet, 8 inches (2.946 meters). The helicopter had a maximum gross weight of 2,800 pounds (1,270 kilograms).
The main rotor, in common to all American-designed helicopters, rotates counter-clockwise as seen from above. (The advancing blade is on the helicopter’s right.) The anti-torque (tail) rotor is mounted to the right side of an angled tail boom extension, in a tractor configuration, and rotates counter-clockwise as seen from the helicopter’s left. (The advancing blade is above the axis of rotation.)
The main rotor is a two-bladed, under-slung, semi-rigid assembly that would be a characteristic of helicopters built by Bell for decades. The main rotor system incorporates a stabilizer bar, positioned below and at right angles to the main rotor blades. Teardrop-shaped weights are placed at each end of the bar, on 100-inch (2.540 meters) centers. The outside diameter of the stabilizer bar is 8 feet, 6.781 inches (2.611 meters). (A similar system is used on the larger Bell 204/205/212 helicopters.)
The H-13J was powered by an air-cooled, normally-aspirated 433.972-cubic-inch-displacement (7.112 liter) AVCO Lycoming VO-435-A1B (O-435-21) vertically-opposed 6-cylinder direct-drive engine. The VO-435 had a compression ration of 7.3:1. It was rated at 220 horsepower at 3,200 r.p.m., maximum continuous power, and 260 horsepower at 3,200 r.p.m. for takeoff. The VO-435-A1B weighed 393.00 pounds (178.262 kilograms).
Engine torque is sent through a centrifugal clutch to a 9:1 gear-reduction transmission, which drives the main rotor through a two-stage planetary gear system. The transmission also drives the tail rotor drive shaft, and through a vee-belt/pulley system, a large fan to provide cooling air for the engine.
Fuel was carried in two gravity-feed tanks, mounted above and on each side of the engine. The total fuel capacity was 34.0 gallons (128.7 liters)
Cruise speed for the H-13J was 87–98 miles per hour (140–158 kilometers per hour), depending on gross weight, and its maximum speed was 105 miles per hour (169 kilometers per hour). The helicopter had a hover ceiling in ground effect (HIGE) of 8,100 feet (2,469 meters). The service ceiling was 15,000 feet (4,572 meters).
Both H-13J Sioux served as presidential aircraft until 1962. They were redesignated UH-13J and continued in use for VIP transportation until 1967.
Bell UH-13J-BF Sioux 57-2729 is in the collection of the Smithsonian Institution National Museum National Air and Space Museum, Steven V. Udvar-Hazy Center, while its sister ship, 57-2728, is at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio, along with Columbine III.
© 2018, Bryan R. Swopes
5 July 1962: Captain Chester R. Radcliffe, Jr., United States Air Force, flew Kaman HH-43B-KA Huskie 60-0263 from Hill Air Force Base, Utah, to Springfield, Minnesota, a distance of 1,429.80 kilometers (888.44 miles). This established a new Fédération Aéronautique Internationale (FAI) World Record for Distance Without Landing.¹
This same helicopter, flown by Captain Walter G. McMeen, set an FAI World Record for Altitude with a 1000 kilogram Payload to an altitude of 8,037 meters (26,368 feet) over the Kaman plant at Bloomfield, Connecticut, 25 May 1961.² On 18 October 1961, again at Bloomfield, Lieutenant Colonel Francis M. Carney set a World Record for Altitude Without Payload when he flew 60-0263 to 10,010 meters (32,841 feet).³ The following week, on 24 October 1961, Colonel Carney set six more world records, flying the HH-43B to 3,000 meters (9,853 feet) in 2 minutes, 41.5 seconds;⁴ 6,000 meters (19,685 feet) in 6 minutes 49.3 seconds;⁵ and to 9,000 meters (29,528 feet) in 14 minutes, 31 seconds.⁶ The following summer, Captain Richard H. Coan set an FAI World Record for Distance Over a Closed Circuit Without Landing when he flew 1,055.16 kilometers (655.65 miles) at Mono Lake, California, 13 June 1962.⁷
A turboshaft engine drove a unique system of counter-rotating and intermeshing rotors to provide lift, thrust and directional control. The counter-rotation cancelled the torque effect so no anti-torque, or tail, rotor was necessary. This allowed all of the engine’s power to drive the main rotor system.
The Huskie was used by the U.S. Air Force, U.S. Navy and Marine Corps, primarily for short range rescue operations. It was operated by two pilots and two rescue crewmen.
The fuselage of the H-43B was 25 feet, 2 inches (7.671 meters) long. Each rotor had a diameter of 47 feet, 0 inches (14.326 meters). It’s height was 15 feet, 6½ inches (4.737 meters). The helicopter’s empty weight was 4,470 pounds (2,028 kilograms) and its maximum gross weight was 8,800 pounds (3,992 kilograms).
The H-43B was powered by one Lycoming T53-L-1B turboshaft engine, rated at 860 shaft horsepower at 21,510 r.p.m. The engine uses a 5-stage axial-flow, 1 stage centrifugal-flow, compressor with a single stage gas producer turbine and single-stage power turbine. A reverse-flow combustion section allows significant reduction in the the engine’s total length. The power turbine drives the output shaft through a 3.22:1 gear reduction. The T53-L-1 is 3 feet, 11.8 inches (1.214 meters) long and 1 foot, 11.0 inches (0.584 meters) in diameter. It weighs 460 pounds (209 kilograms).
The Huskie’s economical cruise speed was 98 miles per hour (158 kilometers per hour), and the maximum speed was 120 miles per hour (193 kilometers per hour). Its hover ceiling out of ground effect (HOGE) was 18,000 feet (5,486 meters), and in ground effect (HIGE) was 20,000 feet (6,096 meters) and it had a range of 235 miles (378 kilometers).
With the call sign Pedro, the HH-43 was a rescue helicopter that served in combat during the Vietnam War.
The record-setting Kaman HH-43B Huskie 60-0263 was last assigned to Detachment 3, 42nd Aerospace Rescue and Recovery Squadron, Kirtland Air Force Base, New Mexico. It is in the collection of the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio. Its distance record still stands.
¹ FAI Record File Number 1258
² FAI Record File Number 13154
³ FAI Record File Number 1870
⁴ FAI Record File Numbers 13057 and 13135
⁵ FAI Record File Numbers 13056 and 13136
⁶ FAI Record File Number 13137
⁷ FAI Record File Number 131258
© 2020, Bryan R. Swopes
30 June 1975: The last operational Douglas C-47 Skytrain transport in service with the United States Air Force, 43-49507, was retired and flown to the National Museum of the United States Air Force at Wright-Patterson Air Force Base, Ohio.
A C-47D, it is on display in the World War II Gallery, painted and marked as C-47A-80-DL 43-15213 of the 91st Troop Carrier Squadron, 439th Troop Carrier Group, during World War II. At the time it was withdrawn from service, 43-49507 had flown a total of 20,831 hours.
43-49507 (Douglas serial number 26768) was built at Oklahoma City as a C-47B-15-DK Skytrain. The C-47B differed from the C-47A in that it was powered by Pratt & Whitney Twin Wasp S3C4-G (R-1830-90) engines. These engines were equipped with two-speed superchargers for improved high-altitude performance. Following World War II, the second speed (“high blower”) was either disabled or removed. Following this modification, the airplane was redesignated C-47D.
The Douglas C-47 Skytrain is a military transport variant of the Douglas Aircraft Company DC-3 commercial airliner. It is an all-metal, twin-engine, low-wing monoplane with retractable landing gear. It was operated by a minimum flight crew of two pilots, navigator, radio operator and mechanic/load master. The airplane’s control surfaces are covered with doped-fabric. The primary differences between the civil DC-3 and military C-47 was the addition of a cargo door on the left side of the fuselage, a strengthened cargo floor, a navigator’s astrodome and provisions for glider towing.
The DC-3 made its first flight 17 December 1935, while the C-47 flew for the first time six years later, 23 December 1941.
The C-47 is 64 feet, 5½ inches (19.647 meters) long with a wingspan of 95 feet (28.956 meters) and height of 17 feet (5.182 meters). The total wing area is 988.9 square feet (91.872 square meters). The angle of incidence is 2°. The wing center section is straight, but outboard of the engine nacelles there is 5º dihedral. The wings’ leading edges are swept aft 15.5°. The trailing edges have no sweep. Empty weight of the C-47D is 17,865 pounds (8,103 kilograms) and the maximum takeoff weight is 33,000 pounds (14,969 kilograms).
The C-47A was powered by two 1,829.4-cubic-inch-displacement (29.978 liter) air-cooled, supercharged R-1830-92 (Pratt & Whitney Twin Wasp S1C3-G) two-row 14-cylinder radial engines with a compression ratio of 6.7:1. These were rated at 1,060 horsepower at 2,550 r.pm., up to 7,500 feet (2,286 meters), maximum continuous power, and 1,200 horsepower at 2,700 r.p.m. at Sea Level for takeoff. Each engine drives a three-bladed Hamilton Standard Hydromatic constant-speed full-feathering propeller with a diameter of 11 feet, 6 inches (3.505 meters) through a 16:9 gear reduction. The R-1830-92 is 48.19 inches (1.224 meters) long, 61.67 inches (1.566 meters) in diameter, and weighs 1,465 pounds (665 kilograms).
The specifications of the Pratt & Whitney Twin Wasp S3C4-G (R-1830-90) installed on the C-47B and C-47D were nearly the same as the -92 engine of the C-47A. Displacement and compression ratio were identical. The engines’ diameters were the same, though the -90 was very slightly longer than the -92—1.85–2.74 inches (4.699–6.960 centimeters), depending on specific variant. Also, the -90 was heavier than the -92 by 25–30 pounds (11.34–13.61 kilograms), again, depending on the specific variant. The R-1830-90 could maintain 1,000 horsepower at 2,550 r.p.m. at 12,500 feet (3,810 meters), and 1,000 horsepower at 2,700 r.p.m. at 14,000 feet (4,267 meters), a significant increase over the -92.
The C-47D has a cruising speed of 161 knots (185 miles per hour/298 kilometers per hour) at 10,000 feet (3,048 meters), and maximum speed of 202 knots (232 miles per hour/374 kilometers per hour) at 3,500 feet (1,067 meters). Its service ceiling was 22,150 feet (6,751 meters). The Skytrain had a maximum range of 1,026 nautical miles (1,181 miles/1,900 kilometers) with full cargo.
The C-47 could carry 9,485 pounds (4,302 kilograms) of cargo, or 27 fully-equipped paratroopers. Alternatively, 24 patients on stretchers could be carried, along with two attendants.
On D-Day, The Sixth of June, 1944, a formation of C-47 Skytrains, nine airplanes abreast, 100 feet (30 meters) from wing tip to wing tip, 1,000 feet (305 meters) in trail, stretching for over 300 miles (483 kilometers), airdropped 13,348 paratroopers of the 82nd and 101st Airborne Divisions, United States Army, and another 7,900 men of the British Army 6th Airborne Division and the 1st Canadian Parachute Battalion, behind the beaches at Normandy, France.
During the Vietnam War, 53 C-47s were converted from their transport role to AC-47 Spooky gunships. These were armed with three fixed, electrically-powered General Electric GAU-2/A .30-caliber (7.62 NATO) Gatling guns firing out the left side of the fuselage. These aircraft were highly effective at providing close air support. The three Miniguns could fire a total of 12,000 rounds per minute.
Douglas Aircraft Company built 10,174 C-47 Skytrains at its factories in Santa Monica and Long Beach, California, and at Oklahoma City, Oklahoma.
© 2018, Bryan R. Swopes