Daily Archives: January 23, 2024

23 January 2003

Artist's conception of Pioneer 10 in the outer solar system. (NASA)
Artist’s conception of Pioneer 10 in the outer solar system. (NASA)

23 January 2003: The final, very weak signal from Pioneer 10 was received on January 23, 2003 when it was 12 billion kilometers (80 Astronomical Units) from Earth.

The space probe was launched from Earth at 01:49:00 UTC, 2 March 1972, aboard an Atlas Centaur rocket.

“On January 1, 2016, Pioneer 10 was predicted to be 114.07 a.u. from the Earth (about 10 billion miles); and traveling at 12.04 km/s (26,900 mph) (relative to the Sun) and traveling outward at about 2.54 a.u. per year. Voyager 2 is projected to pass Pioneer 10 by April 2019. Sunlight takes 14.79 hours to reach Pioneer 10. The brightness of the Sun from the spacecraft is magnitude −16.6. Pioneer 10 is heading in the direction of the constellation Taurus.

“If left undisturbed, Pioneer 10 and its sister craft Pioneer 11 will join the two Voyager spacecraft and the New Horizons spacecraft in leaving the Solar System to wander the interstellar medium. The Pioneer 10 trajectory is expected to take it in the general direction of the star Aldebaran, currently located at a distance of about 68 light years. If Aldebaran had zero relative velocity, it would require more than two million years for the spacecraft to reach it.” — Wikipedia

Pioneer 10 is launched aboard an Atlas Centaur rocket at Space Launch Complex 36A, 01:49:00 UTC, 2 March 1972. (NASA)
Pioneer 10 is launched aboard an Atlas Centaur rocket at Space Launch Complex 36A, 01:49:00 UTC, 2 March 1972. (NASA)

© 2018, Bryan R. Swopes

23 January 1971

Captain Eugene A. Cernan, U.S.N., in the cockpit of NASA 947, a Bell 47G-3B-1, as it hovers in ground effect, circa 1970. (NASA)
Eugene A. Cernan, backup commander, Apollo 14. (NASA)

23 January 1971: NASA Astronaut Eugene Andrew (“Gene”) Cernan, backup commander for Apollo 14, was flying NASA 947, a 1967 Bell Model 47G-3B-1 helicopter, (N947NA, serial number 6665), on a proficiency flight. He intended to practice vertical approaches as a warmup for a lunar landing.

With full fuel tanks, NASA 947 was heavy. Cernan decided to burn off some fuel by flying along the Indian River before the vertical approaches:

     “That gave me a reason to loaf around the sky for a while and invest the extra fuel in some fun flying.

     “Small boats dotted the clear water below and bright islands mounded here and there on the river. Hardly a ripple disturbed the mirrorlike surface. After so many months of hard work and concentration, I couldn’t resist the temptation for a bit of mischief known among pilots as ‘flat-hatting.’ So I nosed over and swooped down from a couple of hundred feet to dance the chopper around island beaches and among the boaters, steadily getting closer to the surface. . .

     “Without realizing the danger, I flew into a trap that was the plague of seaplane pilots. Without ripples, the water provided no depth perception and my eyes looked straight through the clear surface to the reflective river bottom. I had lost sight of the water. But I was in control, or at least I thought so. . . until the toe of my left skid dug into the Indian River.

     “. . . I twisted the collective with my left hand and  applied more power, pulling back on the controls, trying to get the machine to climb out of trouble. A plume of water erupted beneath the skid, then the canopy struck and a rushing tidal wave filled my vision as the helicopter lost any semblance of aerodynamic design. In a single flashing instant, it went from a speed of 100 knots to flat zero with a lurch as severe as any I had ever felt landing on an aircraft carrier or staging in a spacecraft. I crashed with a spectacular explosion.”

The Last Man on the Moon, by Eugene Cernan and Don Davis, St. Martin’s Press, New York, 1999, at Page 258

Gene Cernan hovering one of NASA’s Bell 47 helicopters, circa 1971. (NASA via The Drive)

The Bell 47 was torn apart by the impact. The cabin section, with Cernan still strapped inside, sank to the bottom of the river. As a Naval Aviator, he was trained in under water egress. He freed himself from the wreck and made his way to the surface. Gasoline from the ruptured fuel tanks was floating on the water and had caught fire. Cernan suffered some minor burns, but was otherwise unhurt. He was rescued by fishermen who were nearby.

The location of the crash was in the Indian River near Malabar, Florida.

An accident investigation board, led by Astronaut James A. Lovell, commander of Apollo 13, concluded that the accident was pilot error, in that Cernan had misjudged his altitude when flying over the water.

Colonel James A. McDivitt

A week after the flight crew for Apollo 17 was announced, in a meeting with Dr. Robert R. (“Bob”) Bob Gilruth, Director of the Manned Spacecraft Center, and Christopher C. Kraft, Jr., Deputy Director of MSC and Director of Flight Operations, Colonel James Alton McDivitt, U.S. Air Force, NASA’s Manager of the Apollo Spacecraft Program (and who had commanded Gemini 4 and Apollo 9), insisted that Gene Cernan be grounded for poor judgement and not assigned as commander of Apollo 17.

Chris Kraft wrote:

  “Why didn’t you ask me about this crew?” he [McDivitt] demanded. “Cernan’s not worthy of this assignment, he doesn’t deserve it, he’s not a very good pilot, he’s liable to screw everything up, and I don’t want him to fly.

     I was shocked at how strongly Jim was reacting. “Why didn’t you ask me” he pleaded. “Why didn’t you ask me?” Then he shocked me further. “If you don’t get rid of him, I’ll quit.”

     . . . I called McDivitt and told him that Cernan was staying. . .

     “Thank you,” he said. “You’ll have my resignation shortly.”

Flight: My Life in Mission Control, by Christopher C. Kraft and James L. Schefter, Dutton, New York, 2001, Chapter 23, at Pages 346 and 347

Gene Cernan, along with Ronald E. Evans and Harrison H. Schmitt, lifted off from the Kennedy Space Center aboard Apollo 17, 7 December 1972. On 11 December, he and Schmitt landed at the Taurus-Littrow Valley at the southeastern edge of Mare Serenitatis.

On 14 December 1972, Eugene Andrew Cernan was the last human to stand on the surface of The Moon.

Eugene A. Cernan at the Taurus-Littrow Valley during the third EVA of the Apollo 17 mission. (Harrison H. Schmitt/NASA)

The Bell Model 47, designed by Arthur M. Young of the Bell Aircraft Corporation, Buffalo, New York, was the first helicopter to receive civil certification from the Civil Aviation Administration, predecessor of the Federal Aviation Administration. On 8 March 1946, the aircraft received C.A.A. Type Certificate H-1.

The Bell 47G was the first helicopter manufactured by the Bell Aircraft Corporation at the company’s new plant at Fort Worth, Texas. It was also produced under license by Agusta, Kawasaki and Westland.

Bell 47G-3B1 NASA 822 (N822NA, s/n 6670) in the original factory paint scheme. (NASA EC82-18422A)

The Bell Model 47G-3B-1 was issued Type Certificate 2H-3 on 25 January 1963. It is a 3-place, single-engine light helicopter, operated by a single pilot. The helicopter has dual flight controls and can be flown from either the left or right. The airframe is constructed of a welded tubular steel framework with a sheet metal cockpit. The landing gear consists of two lateral, horizontal tubular cross tubes, and two longitudinal “skids,” curved upward at the front. Ground handling wheels can be attached to the skids. The most distinctive feature of the Bell 47 is the large plexiglass “bubble” canopy. The main rotor flight controls use a system of bell cranks and push-pull tubes. The cyclic and collective are hydraulically boosted. The tail rotor is controlled by pedals and stainless steel cables.

NASA 822, one of NASA’s Bell Model 47G-3B-1 helicopters (N822NA, s/n 6670), photographed 12 August 1977 at the Dryden Flight Research Center. Chief Pilot Donald L. Mallick is in the cockpit. (NASA EC77-8296)

With rotors turning, the Bell 47G-3B-1 has an overall length of 43 feet, 5.55 inches (13.247 meters). From the forward tip of the skids to the aft end of the tail rotor guard, the fuselage is 32 feet, 7.40 inches long (9.942 meters). The main rotor has a diameter of 37 feet, 0.50 inches (11.290 meters). The tail rotor diameter is 5 feet, 10.1 inches (1.781 meters). Height to top of main rotor mast is 9 feet, 3.7 inches (2.837 meters).

The Bell 47G-3B-1 has an empty weight of approximately 1,820 pounds (826 kilograms), depending on installed equipment. Its maximum gross weight is 2,950 pounds (1,338 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, 6.8 inches (2.611 meters). The pilot’s inputs to the cyclic stick are damped through a series of mechanical linkages and hydraulic dampers before arriving at the pitch horns on the rotor hub. The result is smoother, more stable flight, especially while at a hover. The stabilizer bar action is commonly explained as being “gyroscopic,” but this is incorrect. (A similar system is used on the larger Bell 204/205/212 helicopters.)

The Bell 47G-3B-1 used tip-weighted high-inertia metal main rotor blades. The airfoil is symmetrical, using the NACA 0015 profile. The operating range of the main rotor is 322–370 r.p.m.

The working parts of this Agusta-Bell 47G-3B-1 are clearly visible in this photograph. (M. Bazzani/Heli-Archive)

The 47G-3B-1 used an AVCO Lycoming TVO-435-B1A, -B1B, -D1A, or -D1B engine. The TVO-435 is an air-cooled, turbosupercharged 433.976-cubic-inch-displacement (7.112 liter) vertically-opposed, six-cylinder overhead-valve engine with a compression ratio of 7.30:1. It is equipped with a Garrett AiResearch T-1108 turbosupercharger, which provides a constant manifold pressure with decreasing pressure altitude. The engine idles at 1,500 r.p.m. Its normal operating range is 3,000 to 3,200 r.p.m. (3,100–3,200 r.p.m., above 10,000 feet, or 3,048 meters). The TVO-435-B1 has a maximum continuous power rating of 220 horsepower at 3,200 r.p.m., with a manifold pressure of 27.5 inches Hg (0.931 Bar); and a maximum 270 horsepower at 3,200 r.p.m. at 32.8 inches Hg (1.111 Bar) (-B1) or 32.0 inches (1.084 Bar) (-D1) at Sea Level, for takeoff (5-minute limit).

The TVO-435 is 34.73 Inches (0.882 meters) high, 33.58 inches (0.878 meters) wide and 24.13 inches (0.613 meters) deep, and weighs 464.00 pounds (178.26 kilograms) to 481.00 pounds (182.89 kilograms), depending of the specific engine variant.

Engine torque is sent through a centrifugal clutch to a 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 on the forward face of the engine to provide cooling air.

Instrument panel of an Agusta-Bell 47G-3B-1. (M. Bazzani/Heli-Archive)

The Bell 47G-3B1 has a maximum cruise speed of 80 miles per hour (129 kilometers per hour) from 1,000 to 4,500 feet (305–1,372 meters). This decreases to 70 miles per hour up to 10,000 feet (3,048 meters), and 50–60 miles per hour (80–97 kilometers per hour) up to 15,000 feet (4,572 meters). The helicopter’s maximum speed (VNE) is 105 miles per hour (169 kilometers per hour) from Sea Level to 4,500 feet (1,372 meters). Above that altitude, VNE is reduced 7 miles per hour (11.3 kilometers per hour) for every 1,000 foot (305 meters) increase in altitude. Above 15,000 feet, the VNE continues to decrease at 5 miles per hour (8 kilometers per hour) per 1,000 feet (305 meters).

The Bell 47G-3B-1 demonstrated the ability to over in ground effect (HIGE) at a gross weight of 2,850 pounds (1,293 kilograms) at the summit of Pike’s Peak, 14,115 feet (4,302 meters), in the Rocky Mountains of Colorado. The Density Altitude was approximately 15,000 feet (4,572 meters). At the same gross weight, it hovered out of ground effect (HOGE) at 9,000 feet (2,743 meters), Density Altitude. The helicopter has a maximum altitude limitation of 20,000 feet (6,096 meters).

Fuel is carried in two gravity-feed tanks, mounted above and on each side of the engine. The total fuel capacity is 61.6 gallons (233.2 liters), however, usable fuel is 57 gallons (216 liters). The helicopter has a maximum range of 273 miles (441 kilometers).

In production from 1946 until 1974, more than 7,000 Model 47 helicopters were built, worldwide. Production of the Model 47G-3B-1 began in March 1962 and a total of 337 of were built. The initial sales price was $46,950 (equivalent to $436,325 in 2022 dollars). NASA bought two -G-3B-1s in 1967. Another 415 were built for military customers, designated TH-13T.

This Bell TH-13T-BF Sioux, 66-4292, was in military service from 1966–1972. It is currently registered as N666SM with the civil designation of Bell 47G-3B-1. (FlugKerl2/Wikipedia)

In 2010, the type certificates for all Bell 47 models were transferred to Scott’s Helicopter Service, Le Sueur, Minnesota, which continues to manufacture parts and complete helicopters.

© 2018, Bryan R. Swopes

23 January 1939

H. Lloyd Child, Curtiss-Wright Airplane Division test pilot. (Photograph courtesy of Neil Corbett, Test & Research Pilots, Flight Test Engineers)

23 January 1939:

     Buffalo, N.Y., January 24—(AP)—A Curtiss Hawk 75A pursuit plane, one of 100 being constructed for the French Government, has “substantially exceeded all known speed records” with a free dive of more than 575 miles an hour, it was announced today.

     The speed mark was established yesterday while the ship was undergoing acceptance tests, officials of the Curtiss Aeroplane Division of the Curtiss Wright Corporation said.

     The tests were made by H. Lloyd Child, chief test pilot of the Buffalo Curtiss plant, who said he “felt no ill effects and did not realize” that the speed was presumably the fastest man has ever traveled.”

     National Aeronautic Association officials said that no Federation Aeronautique Internationale records “even approached this speed.”

     The speed of the dive was so great that the marker on the recording airspeed indicator exceeded the instrument’s range and moved off the paper on which the graph of the dive was recorded.

     Aviation experts, who declined to be quoted directly, estimated that the speed might have exceeded 600 miles per hour, compared with the normal falling rate for a 170-pound man of 150 miles an hour.

     The dive was begun at an altitude of 22,000 feet, and the record speed was attained during a 9,000 foot dive.

     At no time during the dive, Child said, did the engine exceed 2,550 revolutions a minute, its normal rated speed in level flight. Hence, he explained, the strain on the motor during the dive was not increased, but was held to the speed of normal operation by the Curtiss electric propeller, with its unlimited blade pitch range.

     Since the motor’s speed was kept at normal during the dive, it was a “free,” rather than a “power” dive as when the motor throttle is opened wide, aviation experts explained.

     Previously, company officials explained, a limiting factor in the speed at which an airplane could dive was the engine’s revolutions each minute, since overspeeding would result to serious damage to the motor.

     The Curtis Hawk 75A pursuit plane is similar to the Curtiss P-36A, the standard pursuit airplane of the United States Army Air Corps.

     It carried two machine guns and is equipped to carry bombs under each wing when on a fighting mission.

     The greatest previously registered speed was 440.681 miles an hour, made by Francesco Agello of Italy over a three-kilometer course in level flight October 23, 1934.

     The world’s land speed record is held by George E. T. Eyston of England at 357.5 miles an hour, established September 16, 1938.

The Cincinnati Enquirer, Vol. XCVIII, No. 291, Wednesday, January 25, 1939, at Page 1, Columns 1 and 2

A U.S. Army Air Corps Curtiss-Wright P-36 Hawk, 12 MD, assigned to Wright Field for flight testing. (U.S. Air Force)

The Oakland Tribune reported:

‘Faster Than Any Man Alive,’ Flier Says After Diving 575 M.P.H.

     BUFFALO, N.Y., Jan. 25.—(AP)—A test pilot who free-power dived a heavily armed pursuit airplane at more than 575 miles per hour claimed today the distinction of having traveled “faster than any other human being.”

     Chief test pilot H. Lloyd Child dropped a Curtiss Hawk 75A through the clouds above Buffalo Airport yesterday at almost 1000 feet a second to exceed “all known speed records,” the Curtiss aeroplane division of the Curtiss-Wright Corporation announced.

     Child was testing the plane for the French Army, which has purchased 100 of the ships. The terrific speed was recorded on instruments installed by the French Government’s representatives, who witnessed the flight.

     The velocity was so great the marker on the indicator exceeded the instrument’s range and moved off the paper roll. Aviation experts said Child probably exceeded 600 miles per hour.

     “I didn’t feel anything,” the test pilot commented, “it was all over too quickly.”

     Child said the dive was part of a day’s work.

     “No danger at all, I would say,” he commented.

     His spare time hobby, skiing, however, “is awful dangerous,” Child asserted.

     “I wouldn’t be surprised if someone would exceed my speed soon. A diving speed of 700 miles per hour is within the realm of possibility,” he added.

Oakland Tribune, VOL. CXXX—NO. 25, Wednesday, January 25, 1939, Page 3, Columns 2 and 3

The prototype Curtiss-Wright Model 75 Hawk, X17Y, s/n 11923. (Curtiss-Wright Corporation)

The Curtiss-Wright Model 75 was a single-seat, single-engine, low wing monoplane with retractable landing gear. The airplane was designed by Donovan Reese Berlin. Curtiss-Wright intended to offer it as a pursuit for the U.S. Army Air Corps. H. Lloyd Child took the prototype, X17Y,¹ for its first flight 6 May 1935.

Donovan Reese Berlin. A scale model of the Model 75 Hawk stands on his desk. (Niagara Aerospace Museum)

After evaluation by the Air Corps at Wright Field, the rival Seversky Aircraft Corporation SEV-1XP was selected by the Air Corps and 77 P-35s were ordered. Don Berlin worked on improving the Model 75, and in 1937, the Air Corps ordered 210 Curtiss P-36As.

Curtiss-Wright P-36A Hawk. (U.S. Air Force)

Curtiss-Wright also offered versions of the Hawk 75 to foreign governments. Variants were available with fixed or retractable gear, a choice of Pratt & Whitney Twin Wasp or Wright Cyclone engines, and various combinations of machine gun and cannon armament.

The Curtiss Hawk 75 A was 28.8 feet (8.78 meters) long with wingspan of 37.3 feet (11.37 meters) and height of 9.25 feet (2.82 meters). The total wing area was 236.0 square feet (21.93 square meters). With a Pratt & Whitney engine, the airplane had an empty weight of 4,713 pounds (2,127.3 kilograms), and gross weight of 5,922 pounds (2,675.7 kilograms).

French Armée de l’air Curtiss H75-C1 chasseur. (Armée de l’air)

The Armée de l’air initially ordered 100 Hawk 75A-1s, designated H75-C1 in French service. Pratt & Whitney Twin Wasp engines (including spares) were ordered separately. They were delivered to France for final assembly, and were unpainted. These airplanes had minor differences from U.S. Army Air Corps P-36As. For example, the instrument markings were metric. It was French custom to have the throttle off when pushed full forward, and wide open when pulled rearward. The pilot’s seat was different in order to fit the standard French parachute.

The French H75-A1 was powered by an air-cooled, supercharged, 1,829.39-cubic-inch-displacement (29.97 liter) Pratt & Whitney Twin Wasp SC-G [Specification Number PW-5028-C]. This was a two-row 14-cylinder radial engine with a compression ratio of 6.7:1. The SC-G was rated at 900 horsepower at 2,550 r.p.m. at 11,000 feet (3,353 meters), and 1,050 horsepower at 2,700 r.p.m., for take off. The engine drove a three-bladed, 10 foot, 1½ inch (3.086 meters) diameter Curtiss Electric constant-speed propeller through a 16:9 gear reduction. The SC-G was 48.00 inches (1.219 meters) in diameter, 59.90 inches (1.521 meters) long, and weighed 1,423 pounds (645 kilograms).

The Hawk 75A-1 had a maximum cruise speed of 260 miles per hour (418 kilometers per hour) at 19,000 feet (5,790 meters). Its maximum speed was 258 miles per hour (413 kilometers per hour) at Sea Level, 290 miles per hour at 8,200 feet (2,500 meters), and 303 miles per hour (488 kilometers per hour) at 19,000 feet (5,790 meters). Although Child demonstrated a dive at over 575 miles per hour, in service, the Hawk was restricted to a maximum dive speed of 455 miles per hour (732 kilometers per hour). The airplane had a service ceiling of 32,800 feet (9,997 meters), and absolute ceiling of 33,700 feet (10,272 meters).

The Armée de l’air H75A-1 was armed with four FN-Browning de Belgique mle 1938 7.5 mm. × 54 mm MAS machine guns, with two mounted on the engine cowl, synchronized to fire through the propeller arc, and one in each wing. 2,200 rounds of ammunition were carried. The 7.5 mm (the bullet diameter was actually 7.78 mm, or .306-caliber) was a shorter, less powerful cartridge than the .303 British (7.7 × 56 mm) or U.S. standard .30-06 Springfield (7.62 × 63 mm) cartridges.

France followed with orders for Hawk 75A-2, 75A-3 and 75A-4 fighters. These had different combinations of guns and engine variants.

After the surrender of France to invaders from Nazi Germany, many Curtiss Hawks made their way to England. In service with the Royal Air Force, these airplanes were called the Mohawk.

Curtiss H75-C1s in service with France, World War II. (Armée de l’air)

Henry Lloyd Child was born at Philadelphia, Pennsylvania, 25 May 1904, the second of two children of Edward Taggart Child, a consulting engineer in shipbuilding, and Lillian Rushmore Cornell Child. He was baptized at the Church of the Good Shepherd, Rosemont, Pennsylvania, 22 December 1913. Child graduated from Flushing High School in Flushing, New York, then attended the Haverford School in Philadelphia.

Henry Lloyd Child, 1926. (The Class Record)

“Skipper” Child majored in mechanical engineering at the University of Pennsylvania where he was a member of the Hexagon Senior Engineering Society and the Phi Sigma Kappa (ΦΣΚ) and Sigma Tau (ΣΤ) fraternities. He was a member of the varsity and all-state soccer team, and also played football and tennis. Child graduated with a bachelor of science degree, 15 June 1926.

After graduation from college, Child went to work for the Curtiss-Wright Corporation as an engineer.

Child joined the United States Navy, 23 November 1927. He was trained as a pilot at Naval Air Station Hampton Roads, Norfolk, Virginia, and was commissioned as an Ensign. He was promoted to lieutenant (junior grade), 7 November 1932, and to lieutenant, 11 November 1935.

While maintaining his commission in the Navy, Child returned to Curtiss-Wright as a test pilot.

Mr. And Mrs. Henry Lloyd Child (née Allene Anne Gausby), 28 October 1939.

Henry Lloyd Child married Miss Allene Ann Gausby of Hamilton, Ontario, Canada, 28 October 1939. They had met in July 1938, while playing in a tennis tournament at Muskoka, Northern Ontario. They would have a daughter, Beverley L. Child.

Miss Allene Anne Gausby

H. Lloyd Child worked for Lockheed from 1958 to 1968, when he retired. He died at Palmdale, California 5 August 1970 at the age of 66 years.

H. Lloyd Child’s high speed dive was the subject of an 8-page article in “True Comics” , November 1941. (Parents’ Magazine Press)

See: http://comicbookplus.com/?dlid=24805

Curtiss advertisement, 1940. (Curtiss-Wright Corporation)

¹ At this time, American experimental aircraft were prohibited from carrying the national identifier, “N-,” to lead their registration mark.

© 2022, Bryan R. Swopes

23 January 1909

The Blériot XI in flight, May 1909. (Library of Congress Prints and Photographs Division)
Louis Charles Joseph Blériot. (Library of Congress)
Louis Charles Joseph Blériot. (Library of Congress)

23 January 1909: The Blériot XI made its first flight at Issy-les-Moulineaux, near Paris, France. The airplane was flown by Louis Charles Joseph Blériot. It was designed by Raymond Saulnier and was a development of the earlier Blériot VIII.

Saulnier later founded Morane-Saulnier Aviation—Sociètè Anonyme des Aèroplanes Morane-Saulnier—with the Morane brothers, Léon and Robert.

The Blériot XI was a single-seat, single-engine monoplane. It was 26.24 feet (7.998 meters) long with a wingspan of 25.35 feet (7.727 meters) and overall height of 8 feet (2.438 meters). It had an empty weight of 507 pounds (229.9 kilograms).

Raymond Saulnier

(Sources give conflicting specifications for the Blériot XI, probably because they were often changed in an effort to improve the airplane. Dimensions given here are from the three-view drawings, below.)

In its original configuration, the airplane was powered by an air-cooled, 3.774 liter (230.273 cubic inches) R.E.P.  two-row, seven-cylinder fan engine (or “semi-radial”) which produced 30 horsepower at 1,500 r.p.m., driving a four-bladed paddle-type propeller. The R.E.P. engine weighed 54 kilograms (119 pounds). This engine was unreliable and was soon changed for an air-cooled 3.117 liter (190.226 cubic inch) Alessandro Anzani & Co., 60° three-cylinder “fan”-type radial engine (or W-3) and a highly-efficient Chauvière Intégrale two-bladed propeller. The Anzani engine produced 25 horsepower at 1,400 r.p.m.

Blériot Type XI, front view.
Blériot Type XI, side view.
Blériot Type XI, top view.

The Blériot XI had a maximum speed of 76 kilometers per hour (47 miles per hour) and its service ceiling was 1,000 meters (3,281 feet).

Just over six months from its first flight, on 25 July 1909, Louis Blériot flew his Blériot XI across the English Channel from Calais to Dover. He flew the 25 mile (40 kilometer) distance in 36 minutes. The airplane was slightly damaged on landing.

Blériot’s original airplane is in the collection of the Musee des Arts et Metiers, Paris, France.

The Blériot XI was a successful and influential design. It was widely used by both civilian and military aviators.

The original Blériot XI at Musee des Arts et Metiers (PHGCOM. Use authorized.)
The original Blériot XI at Musee des Arts et Metiers (PHGCOM. Use authorized.)

© 2019, Bryan R. Swopes