9 August 1884

Aviation, , , , , , , , ,
Photo prise par l’observatoire de Meudon.par l’astronome Jules Janssen.

9 August 1884: At the parade grounds at Chalais-Meudon, a town on the banks of the Seine near Paris, France, engineers Charles Renard and Arthur Constantin Krebs made the first controllable free flight when they piloted their airship, La France, over an approximately 4¾ mile (7.6 kilometers) course and returned to their starting point. The airship completed the circuit in 20 minutes at an average speed of 15.75 feet per second (10.74 miles per hour, or 17.28 kilometers per hour).

Track of La France, 9 August 1884

Charles Renard later said,

“As soon as we had reached the top of the wooden plateaus which surrounded the valley of Chalais we started the screw, and had the satisfaction off seeing the balloon immediately obey it, and readily follow ever turn of the rudder. We felt we were absolutely masters of our own movements, and that we could traverse the atmosphere in any direction as easily as a steam launch could make its evolutions on a calm lake. After having accomplished our purpose we turned our head toward the point of departure, and we soon saw it approaching us. The walls of the park of Chalais were passed anew, and our landing appeared at our feet about 1,00 feet below the car. The screw was then slowed down, and at a pull of the safety valve started the descent, during which, by means of the propeller and rudder, the balloon was maintained directly over the point where our assistants awaited us. Everything occurred according to our plan, and the car was soon resting quietly upon the lawn from which we had started.”

—The Practical Engineer, Volume 9, Number 371, Friday, 6 April 1894, Page 266, Column 1

From 9 August 1884 to 23 September 1885, La France made seven flights and was able to return to its starting point five times. On its final flight, it reached an average speed of 21.33 feet per second (14.54 miles per hour, or 23.40 kilometers per hour).

Plan de l’enclos de l’étang de Chalais et de ses dépendances. (Bibliothèque nationale de France)

La France was a powered, steerable, gas balloon, approximately 167 feet long (50.9 meters) and 27½ feet (8.4 meters) in diameter. Buoyancy was provided by 65,000 cubic feet (1,841 cubic meters) of hydrogen.

Under the balloon envelope hung a 108 foot (32.9 meter) long gondola made of bamboo and covered with silk. This was where the airmen and any passengers, the 8½ horsepower (6.25 kilowatts) electric motor and a chromium chloride storage battery were placed. The motor weighed 220.5 pounds (100 kilograms), and the battery, 580 pounds (263 kilograms.)

At the forward end of the gondola was a four-bladed wooden propeller with a 23-foot (7.0 meters) diameter and 28-foot (2.4 meters) pitch, providing thrust to drive the airship. The propeller was driven by a 49 foot (14.9 meters) drive shaft. On the 9 August flight, the propeller turned 42 r.p.m. On later flights, this was increased to a maximum 57 r.p.m.

La France was controlled by a rudder and elevator. A sliding weight allowed for changes in the center of gravity.

Drawing of le dirigeable ballon La France de Charles Renard et Arthur Krebs.

La France was designed and built by Captain Paul Renard, Captain Charles Renard and Captain Arthur Constantin Krebs, all officers of the French Armée de Terre Corps du Génie (Corps of Engineers) at the central military aeronautics establishment at Chalais-Meudon.

Charles Renard

Charles Renard was born at Damblain, Viosges, France, 23 November 1847. In 1873, he had developed an unmanned glider which was controlled by a pendulum device linked to its control surfaces. The glider was flown from a tower at Arras.

Renard also developed the powered Renard Road Train, in which the trailers were powered by drive shafts from the forward power car, and each car was steered through a system of linkages attached to the car ahead of it. He also developed the concept of preferred numbers. (ISO 3)¹

Charles Renard remained in charge of the aeronautical establishment at Chalais-Meudon until his death. He committed suicide, 13 April 1905.

Arthur Constantin Krebs was born 16 November 1850 at Vesoul, France.

Arthur Constantin Krebs

Krebs was a prolific inventor. Following his work with La France, he completed the development of Gymnote (Q1), the world’s first all-electric submarine. His work on automobiles was extensive. He developed the concept of the front engine/rear wheel drive (Systeme Panhard); engine balancing; caster in the steering and suspension system, which allowed the steering wheels to self-center; the steering wheel; shock absorbers; four-wheel drive and four-wheel steering, etc. He invented the electric brake dynomometer which is used to measure power output of engines.

Arthur Krebs died 22 March 1935.

Airship La France at Hangar Y, Chalais-Meudon, circa 1885. (NASM)

¹ “Preferred numbers were first utilized in France at the end of the nineteenth century. From 1877 to 1879, Captain Charles Renard, an officer in the engineer corps, made a rational study of the elements necessary in the construction of lighter-than-air aircraft. He computed the specifications for cotton rope according to a grading system, such that this element could be produced in advance without prejudice to the installations where such rope was subsequently to be utilized. Recognizing the advantage to be derived from the geometrical progression, he adopted, as a basis, a rope having a mass of a grams per metre, and as a grading system, a rule that would yield a tenth multiple of the value a after every fifth step of the series. . . .”

—ISO 17:1973, International Organization for Standardization

© 2017, Bryan R. Swopes

8 August 1957

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Mikoyan-Gurevich Ye-50/3 (Mikoyan Design Bureau via The Corner of the Sky)
Nikolay Arkadevich Korovin

8 August 1957: At Ramenskoye Airfield, Moscow, Russia, senior test pilot Lieutenant Colonel Nikolay Arkadevich Korovin (Коровин Николай Аркадьевич) was scheduled to take an experimental prototype interceptor to an altitude of 20,000 meters (65,617 feet).

The airplane was the Mikoyan-Gurevich Ye-50/3 (also known as the E-50/3). It was powered by an afterburning turbojet engine and a liquid-fueled rocket engine. This was the third prototype of the series.

The three Ye-50 prototypes were variants of the MiG 21. They were developed from the earlier MiG Ye-2, with a rocket engine installed. This was not merely a booster engine, but the aircraft carried sufficient fuel for as much as 20 minutes of rocket-assisted flight. A planned production interceptor, the Ye-50A, was designated MiG 23U. Only one of these was built.

Mikoyan-Gurevich Ye-50/3 (Mikoyan Design Bureau via The Corner of the Sky)

The Ye-50/3 differed from Ye-50/2 with an increased fuel capacity and extended air intake with sharp leading edge. The Ye-50/3 was 4.85 meters (48.72 feet) long with a wingspan of 8.11 meters (21.61 feet). The aircraft had an empty weight of 5,920 kilograms (13,051 pounds), and maximum takeoff weight of 8,500 kilograms (18,739 pounds).

The Ye-50/3 was powered by an A.A. Mikulin AM-9E afterburning turbojet engine rated at 3,800 kilograms force ( pounds thrust) and a liquid-fueled Dushkin S-155 rocket engine. The S-155 used a hypergolic mixture of nitric acid and kerosene as fuel. It produced 1,300 kgf (2,866 pounds of thrust).

Mikoyan-Gurevich Ye-50/3 (Mikoyan Design Bureau via The Corner of the Sky)

The Ye-50/3 had been completed in April 1957. Prior to 8 August, Ye-50/3 had made 10 test flights, 6 of which successfully used the rocket engine. It had a maximum speed of 2,460 kilometers per hour (1,529 miles per hour), or Mach 2.33. The service ceiling was 23,000 meters (75,460 feet. Its range was 475 kilometers (295 miles).

The Ye-50/3 was the only one of the three prototypes to be armed. It carried two Nudelman-Rikhter NR-30 30 mm autocannon.

Mikoyan-Gurevich Ye-50/3 (Mikoyan Design Bureau via The Corner of the Sky)

Ramenskoye Airfield was very busy that day. Colonel Korovin’s launch was delayed by traffic on the runway. Finally, he took of at 12:50 p.m. and accelerated into a climb.

At 1:01 p.m., Colonel Korovin radioed that the aircraft was in a spin. 30 seconds later, he called that he was ejecting.

The Ye-50/3 crashed near the village of Radovitsy, approximately 100 kilometers (62 miles) southeast of Ramenskoye. The body of Colonel Korovin was located about 150 meters (164 yards) from the crash site, still in his ejection seat. The parachute had not opened, and the test pilot had been killed on impact.

The accident investigation found that during the delay to takeoff, the liquid oxidizer accumulated in the combustion chamber. This caught fire as the prototype took off. The rocket engine’s turbopump exploded. The explosion damaged the flight control system and the prototype caught fire. The fire burned away a portion of the airplane’s vertical fin. When it entered a spin, Colonel Korovin was unable to recover. It was found that he had removed his gloves and tried to manually pull the ejection seat parachute release cable, but to no avail.

On 9 September 1957, Lieutenant Colonel Korovin was posthumously named a Hero of the Soviet Union.

Cockpit of Mikoyan-Gurevich Ye-50/3. (Mikoyan Design Bureau via The Corner of the Sky)
Коровин Николай Аркадьевич

Nikolay Arkadevich Korovin was born 7 May 1920 at the village of Galanovo in the Votsk Autonomous Oblast (now, the Udmurt Republic). His family were peasants who worked on a collective farm. Korovin completed six grades of formal education.

In 1938 Korovin joined the Red Army. He received further education at a military school in Perm, a city in Russia near the Ural Mountains, graduating in 1939. The following year, he completed pilot training at the Stalingrad Military Aviation School.

From 1941 through 1944, Korovin served as a pilot instructor at Chkalovskaya (now Orenburg, Kazakhstan). In March 1944, he was assigned to combat operations, first with the 91st Guards Aviation Regiment (Ground Attack), and then the 92nd Guards. He fought on the second Ukrainian Front, and in Hungary, Checkoslavakia and Austria. He flew 66 combat missions in the Ilyushin Il-2 Штурмовик (Šturmovík) during the Great Patriotic War.

The Ilyushin Il-2 Šturmovík was the most-produced aircraft of the Second World War. (NASM)

Korovin remained in the Soviet Air Force following the War. He graduated from a senior officers tactical school at Taganrog, Rostov Oblast, in 1950, and then, in 1951, became a senior test pilot for the State Red Banner Scientific-Testing Institute for the Air Force (GK NII VVS). In 1955, Korovin flew government tests of the MiG 19.

During his military career, Lieutenant Colonel Nikolay Arkadevich Korovin was awarded the Order of Lenin, Order of the Red Banner, Order of the Patriotic War 1st Degree, and Order of the Red Star (two awards). His remains were buried at the military cemetery at Chkalovskaya.

© 2017, Bryan R. Swopes

8 August 1955

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8 August 1955: While being carried aloft by a Boeing B-29 Superfortress, the Bell X-1A was being readied for it’s next high-altitude supersonic flight by NACA test pilot Joe Walker. During the countdown, an internal explosion occurred. Walker was not injured and was able to get out. The X-1A was jettisoned. It crashed onto the desert floor and was destroyed.

A number of similar explosions had occurred in the X-1D, X-1-3 and the X-2. Several aircraft had been damaged or destroyed, and Bell Aircraft test pilot Skip Ziegler was killed when an X-2 exploded during a captive flight. A flight engineer aboard the B-29 mothership was also killed. The B-29 was able to land but was so heavily damaged that it never flew again.

Debris from the X-1A crash site was brought back to Edwards AFB for examination. It was discovered that a gasket material used in the rocket engine fuel systems was reacting with the fuel, resulting in the explosions. The problem was corrected and the mysterious explosions stopped.

Test pilot Joe Walker “horsing around” with the Bell X-1A, 1955. (NASA)

© 2015, Bryan R. Swopes

8 August 1946

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Convair XB-36 Peacemaker 42-13570 engine run-up
The prototype Consolidated-Vultee XB-36, 42-13570, stands at the end of the runway with all six engines running. (U.S. Air Force)

8 August 1946: At Fort Worth, Texas, the Consolidated-Vultee Aircraft Corporation XB-36 prototype, 42-13570, made its first flight. Convair test pilots Beryl Arthur Erickson and G.S. “Gus” Green, along with Chief Flight Test Engineer James D. “J.D.” McEachern, were in the cockpit. Six other crew members were aboard.

Chief Test Pilot Beryl Arthur Erickson. (Convair)

In a 1992 interview published in Code One Magazine, Erickson said that he and his crew had been ready to take off at 5 a.m., but they didn’t get their release until noon. The Texas summer temperature was 100 degrees (37.8 °C.), but inside the cockpit, the temperature was 140° F. (60 °C.) The engines were overheating and the oil pressure was low. When they pushed the throttles forward, the XB-36 accelerated smoothly and lifted off at 110 knots (126.6 miles per hour, 203.7 kilometers per hour). The retired test pilot said, “The XB-36 controlled nicely in the takeoff run and in the transition to steady climb. We flew conservatively with the gear down. The flight was uneventful and lasted thirty-eight minutes.”

Chief Test Pilot Beryl Arthur Erickson at the aircraft commander’s station of the Consolidated-Vultee XB-36 long-range heavy bomber. (Code One).

The B-36 was the largest and heaviest airplane built up to that time. It was designed as a long-range heavy bomber, able to reach targets on the European continent from the United States and return, should England fall to Nazi Germany during World War II. With the end of the war, its purpose was changed to that of a long range strategic bomber, carrying large nuclear weapons that weren’t even imagined when the design process had begun.

A size comparison between the Convair XB-36 prototype and a Boeing B-29 Superfortress.
A size comparison between a Boeing B-29-55-BA Superfortress, 44-84017, and the Consolidated-Vultee XB-36 prototype, Carswell AFB, June 1948. (U.S. Air Force Historical Research Agency)

The XB-36 was 162 feet, ½ inch (49.390 meters) long with a wing span of 230 feet (70.104 meters), nearly 90 feet longer than that of the B-29 Superfortress that it would replace. Its height was 46 feet, 9-7/8 inches (14.272 meters) to the tip of the vertical fin. The wings’ leading edges were swept aft 15° 5′ 39″, and the trailing edges, 3°. They had 2° dihedral. The wings’ angle of incidence was 3° and they incorporated 2° of negative twist. The total wing area was 4,772 square feet (443.33 square meters). The prototype’s empty weight was 131,240 pounds (59,530 kilograms), and it had a maximum gross weight of 274,929 pounds (124,706 kilograms).

Convair XB-36 three-view illustration with dimensions. (U.S. Air Force)

The XB-36 was powered by six air-cooled, supercharged, 4,362.49 cubic-inch-displacement (71.489 liter) Pratt & Whitney Wasp Major TSB1P-G (R-4360-25) 28-cylinder four-row radial engines, with a normal power rating of 2,500 horsepower at 2,550 r.p.m. to 5,000 feet (1,524 meters), and 3,000 horsepower at 2,700 r.p.m. for takeoff. They were mounted inside the wings. The engines were arranged in a “pusher” configuration with intake and cooling air entering through inlets in the wing leading edge. They drove three-bladed Curtiss propellers with a diameter of 19 feet (5.8 meters) through a 0.381:1 gear reduction. The R-4360-25 was 9 feet, 1.75 inches (2.788 meters) long, 4 feet, 4.50 inches (1.334 meters) in diameter, and weighed 3,483 pounds (1,580 kilograms).

The airplane’s estimated maximum speed was 347 miles per hour (558 kilometers per hour) at 35,000 feet (10,668 meters) and the cruising speed, 216 miles per hour (348 kilometers per hour). The service ceiling was predicted at 36,080 feet (10,997 meters) with all six engines running. It had an estimated range of 9,430 miles (15,176 kilometers) with a 10,000 pound (4,536 kilogram) bomb load.

The prototype Convair XB-36, 42-13570, lifts off the runway at Fort Worth, Texas. (U.S. Air Force)
The prototype Consolidated-Vultee XB-36, 42-13570, lifts off the runway at Fort Worth, Texas. (U.S. Air Force)

The bomber was designed to carry a maximum bomb load of 72,000 pounds (32,659 kilograms): as many as 132 500-pound bombs; 72 1,000 pound; 44 1,600 pound; 28 2,000-pound; or 12 4,000-pounders. Defensive armament was planned as two 37mm cannon in each of the forward upper and lower turrets, with 100 rounds of ammunition per gun; four .50-caliber machine guns in the rear upper and lower turrets with 1,000 rounds per gun; and one 37 mm cannon and two .50-caliber machine guns in the tail. The tail cannon would have 300 rounds, and the machine guns, 1,000 rounds per gun.

After testing, improvements were incorporated into the second prototype, YB-36 42-13571. In June 1948, the XB-36 was modified with R-4360-41 engines, and the main landing gear was changed from a single-wheel design to a 4-wheel bogie. With these and other changes the XB-36 was redesignated YB-36A. It was used for continued testing for the next several years, but was eventually stripped of its engines and equipment and used for firefighter training at the adjacent Carswell Air Force Base.

The YB-36 was selected for production as the B-36A Peacemaker. The B-36 series was produced in both bomber and reconnaissance versions and was in front line service from 1949 to 1959. Beginning with the B-36D, four turbojet engines were mounted beneath the wings in pods similar to those on the Boeing B-47 Stratojet, greatly increasing the bomber’s performance. A total of 384 were built. Only five still exist. The Peacemaker was never used in combat.

The Convair XB-36 in flight. (U.S. Air Force)
The Consolidated-Vultee XB-36 prototype, 42-13570, in flight. (U.S. Air Force)

© 2023, Bryan R. Swopes

8 August 1945

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Fat Man, Nuclear Bomb, Mark III, being prepared at Tinian, Marshall Islands, 8 August 1945. (U.S. Air Force)

“So, the next day, Fat Man, the two armored steel ellipsoids of its ballistic casing bolted together through bathtub fittings to lugs cast into the equatorial segments of the implosion sphere, its boxed tail sprouting radar antennae just as Little Boy’s had done. By 2200 on August 8 it had been loaded into the forward bomb bay of a B-29 named Bockscar after its usual commander, Frederick Bock, but piloted on this occasion by Major Charles W. Sweeney. Sweeney’s primary target was the Kokura Arsenal on the north coast of Kyushu; his secondary was the old Portuguese- and Dutch-influenced port city of Nagasaki, the San Francisco of Japan, home of the country’s largest colony of Christians, where the Mitsubishi torpedoes used at Pearl Harbor had been made.”

—The Making of the Atomic Bomb, by Richard Rhodes, Simon and Schuster, New York, 1986, Chapter 19 at Page 739.

The Mark III “Fat Man” bomb loaded on its carrier, 8 August 1945. (Manhattan Engineer District)

Fat Man was an implosion-type fission bomb, using plutonium (Pu-239) as the nuclear material. It was a very complex device which used 32 precisely-shaped explosive charges surrounding the spherical plutonium-alloy core, detonating with enough force to compress the core to double its normal density. This caused it to reach “critical mass” and the fission chain reaction began.

The Mark III implosion bomb and its trailer are lowered into the pit in preparation for loading aboard Bockscar, 8 August 1945. (U.S. Air Force)
The Mark III implosion bomb and its trailer are lowered into the pit in preparation for loading aboard Bockscar, 8 August 1945. (U.S. Air Force)

The Mark III bomb, unlike the gun-type “Little Boy,” required testing before combat use. The nuclear component of the bomb, called “Gadget,” had been exploded at 05:29:45 a.m., Mountain War Time, 16 July 1945, at the Trinity Site of the Alamogordo Test Range, in the Jornada del Muerta desert of New Mexico. The explosive yield of the detonation was estimated to be equivalent to 20–22,000 tons of TNT.

The fully assembled combat weapon was 12 feet, 8⅜ inches ¹ (3.261 meters) long, 5 feet, ¼ inch ² (1.530 meters) in diameter, and weighed approximately 10,300 pounds (4,672 kilograms).

Rear fuselage of Bockscar, B-29 44-27297, at Tinian. Note the “Triangle N” and “77” codes. The Enola Gay is in the background. (U.S. Air Force)

¹ Overall length, ± ¼ inch

² Overall diameter, ± ⅛ inch

© 2017, Bryan R. Swopes