Tag Archives: World War II

14 August 1942

Lockheed P-38F Lightnings at Iceland during the summer of 1942. 2d Lt. Elva E. Shahan’s P-38F-1-LO, 41-7540, is at the left of the photograph with the number 42 on its nose. (U.S. Air Force)

14 August 1942: The 27th Fighter Squadron (Twin Engine), 1st Fighter Group, VIII Fighter Command, was ferrying its Lockheed P-38 Lightning fighters across the North Atlantic Ocean from Presque Isle, Maine to England as part of Operation Bolero. Iceland was a mid-Atlantic fuel stop on the Northern Ferry Route.

Just over a week earlier, 6 August 1942, 30 Curtiss-Wright P-40C Warhawks of the 33rd Fighter Squadron had been flown off the aircraft carrier USS Wasp (CV-7). Among the 32 Army Air Corps pilots who boarded the carrier with the fighters at Norfolk, Virginia, was Second Lieutenant Joseph D.R. Shaffer, U.S.A.A.C., service number O-427002.

A Curtiss-Wright P-40C Warhawk, Iceland, 1942. (San Diego Air & Space Museum)
Major John H. Weltman, USAAF. Major weltman's P-38 Lightning was the first Army Air Forces aircraft to be hit by German gunfire during World War II. (U.S. Air Force)
Major John H. Weltman, USAAF. Major Weltman’s P-38 Lightning was the first Army Air Forces aircraft to be hit by German gunfire during World War II. (U.S. Air Force)

On the morning of 14 August, a Royal Air Force Northrop N-3PB Nomad of No. 330 Squadron (Norwegian) tracked a German Luftwaffe Focke-Wulf Fw 200 C-4 Condor four-engine maritime reconnaissance bomber, marked NT+BY, flying near a convoy south of the island. The bomber then proceeded northward and overflew the peninsula west of Reykjavik.

Lieutenant Shaffer, his squadron now assigned to the 342d Composite Group, Iceland Base Command, one of the units responsible for the air defense of Iceland, located and attacked the Condor with his P-40, damaging one of the bomber’s engines.

At 11:15 a.m., two P-38s of the 27th Squadron, flown by Major John W. Weltman and Second Lieutenant Elza E. Shahan, followed up Shaffer’s attack. Shahan was flying Lockheed P-38F-1-LO Lightning, serial number 41-7540.

The Fw 200 was hit in and around the bomb bay. It exploded and went into the sea approximately 8 miles northwest of Grótta Point. Its crew, F Ofw. Fritz Kühn, Ofw. Phillip Haisch, Ofw. Ottmar Ebner, Uffz. Wolgang Schulze, Ofw. Arthur Wohlleben and Ofw. Albert Winkelmann were all killed.

This was the very first U.S. Army Air Forces air combat victory in the European Theater of Operations during World War II. Lieutenants Shaffer and Shahan both shared credit for the victory. They were awarded the Silver Star for their actions.

A Focke-Wulf Fw 200 C-3 Condor, SG+KS, (Werk-Nr. 0043), similar to the bomber destroyed by Shaffer and Shahan, 14 August 1942. (Photograph by Walter Frentz. Bundesarchiv)

© 2015, Bryan R. Swopes

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14 August 1942

Boeing B-17E Flying Fortress 41-2656, “Chief Seattle from the Pacific Northwest,” during a test flight near Seattle, Washington, March 1942. (U.S. Air Force)

14 August 1942: Boeing B-17E Flying Fortress 41-2656, Chief Seattle from the Pacific Northwest, took off from 7 Mile Drome, an airfield near Port Moresby, Territory of Papua,  New Guinea, on its first combat mission. This was a reconnaissance of Rabaul and Kavieng. Mission elapsed time, 8 hours, 40 minutes.

Crew of Chief Seattle at 7 Mile Drome, 11 August 1942. Front row, left to right, Sgt Dennis Craig, Sgt. Tomas Wood. Standing, Sgt Quentin Lakely, Pvt Philip Zumwalt, Sgt. Leslie Stewart, Lt. John Pickering, Lt. Morris Friedman, Lt. Haskell Wexler, Sgt Meyer Levin. (United Press)

Sponsored by the Seattle Post-Intelligencer newspaper, citizens of Seattle contributed $230,535 in War Bonds to purchase the airplane. it was delivered to the United States Army Air Forces (USAAF) by the Mayor of Seattle, Earl Milliken P.G. Johnson, in a ceremony held 5 March 1942. The bomber was assigned to the 435th Bombardment Squadron (Heavy), 19th Bombardment Group (Heavy), Fifth Air Force, in the Southwest Pacific.

Aerial photograph of 7 Mile Drome (Jackson Airfield), 1943. (U.S. Air Force)
B-17s parked in revetments at 7 Mile Drome, 1943. (U.S. Air Force)

Flown by another crew, 41-2656 was attacked by three Mitsubishi A6M3 Navy Type 0 Model 32 (Allied reporting name, “Hamp”) fighters of the Imperial Japanese Navy. It was shot down at 7:40 a.m., 14 August 1942, over the Solomon Sea. Defensive fire from the bomber damaged at least one Zero, but it was able to return to its base.

The B-17E went down in the sea. Its crew were listed as missing, presumed killed in action (KIA). They were 1st Lt. Wilson O. Cook, pilot; F/Sgt. George S. Andrews, co-pilot; 2nd Lt. Hubert S. Mobley, navigator; 2nd Lt. Joseph R. Cunningham, bombardier; SSGT Elwyn O Rahier, Engineer; SSGT John J. Dunbar, assistant engineer; T/Sgt. Irving W. Michael, radio operator; Cpl. Charles M. Hartman, asst. radio; Pvt. David B. Beattie, gunner; and Cpl. Richard K. Pastor, gunner.

© 2019, Bryan R. Swopes

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9 August 1945

Martin-Omaha B-29-35-MO Superfortress 44-27297, Bockscar, at the National Museum of the United States Air Force. (U.S. Air Force)

9 August 1945: Three days after an atomic bomb had been used against the Japanese industrial city of Hiroshima, a second attack was made on Nagasaki. Major Charles W. Sweeney, in command of the Martin-Omaha B-29-35-MO Superfortress 44-27297, named Bockscar, departed Tinian Island in the Marshal Group at 3:47 a.m., and flew to Iwo Jima where it was to rendezvous with two other B-29s, The Great Artiste and The Big Stink, the instrumentation and photographic aircraft for this mission.

Like its sistership, Enola Gay, 44-27297 was a specially modified “Silverplate” B-29. The Silverplate B-29s differed from the standard production bombers in many ways. They were approximately 6,000 pounds (2,722 kilograms) lighter. The bomber carried no armor. Additional fuel tanks were installed in the rear bomb bay. The bomb bay doors were operated by quick-acting pneumatic systems. The bomb release mechanism in the forward bomb bay was replaced by a single-point release as was used in special British Lancaster bombers. A weaponeer’s control station was added to the cockpit to monitor the special bomb systems.

Bockscar had four air-cooled, supercharged, 3,347.662-cubic-inch-displacement (54.858 liter) Wright Aeronautical Division R-3350-41 (Cyclone 18 787C18BA3) two-row 18-cylinder radial engines with direct fuel injection. The R-3350-41 had a compression ratio of 6.85:1 and required 100/130 aviation gasoline. It was rated at 2,000 horsepower at 2,400 r.p.m. at Sea Level, and 2,200 horsepower at 2,800 r.p.m, for take-off. The engines drove four-bladed Curtiss Electric reversible-pitch propellers with a diameter of 16 feet, 8 inches (5.080 meters), through a 0.35:1 gear reduction. The R-3350-41 was 6 feet, 2.26 inches (1.937 meters) long, 4 feet, 7.78 inches (1.417 meters) in diameter and weighed 2,725 pounds (1,236 kilograms).

With the exception of the tail gunner’s position, all defensive armament—four powered remotely operated gun turrets with ten .50-caliber machine guns—were deleted. Their remote sighting positions were also removed. Enola Gay carried 1,000 rounds of ammunition for each of the two remaining Browning AN-M2 .50-caliber machine guns in the tail.

With these changes, the Silverplate B-29s could fly higher and faster than a standard B-29, and the fuel-injected R-3350-41 engines were more reliable. Bockscar had a cruising speed of 220 miles per hour (354 kilometers per hour) and a maximum speed of 365 miles per hour (587 kilometers per hour). Its service ceiling was 31,850 feet (9,708 meters) and its combat radius was 2,900 miles (4,667 kilometers).

Martin-Omaha B-29-35-MO Superfortress 44-27297, Bockscar, in flight. Note "Triangle N" tail code. (U.S. Air Force)
Martin-Omaha B-29-35-MO Superfortress 44-27297, Bockscar, in flight. Note “Triangle N” tail code. (U.S. Air Force)

44-27297, Victor 7, was assigned to aircraft commander Captain Frederick C. Bock and his crew. Major Sweeney and his crew ordinarily flew The Great Artiste. Sweeney’s B-29 had been the the instrumentation aircraft for the Hiroshima mission and there was not time to remove that equipment and re-install it aboard Bock’s bomber, so the crews switched airplanes. For operational security, Bockscar‘s normal identification was changed from the number 7 on the fuselage to 77. The 509th’s tail code of a circle surrounding a forward-pointing arrow was changed to another unit’s “Triangle N” identification.

All of these last minute changes resulted in confusion in contemporary reports as to which B-29 had actually dropped Fat Man on Nagasaki.

Boeing B-29 crew photo taken Aug. 11, 1945, two days after the Nagasaki mission. Note there is no nose art on the aircraft. (U.S. Air Force photo)
Major Charles W. Sweeney’s B-29 crew. (U.S. Air Force)

In Bockscar‘s forward bomb bay was a 10,213 pound (4,632 kilograms) bomb called Fat Man. This was a completely different and much more complex weapon than the Little Boy (Mark I) atomic bomb dropped by Colonel Paul Tibbet’s Enola Gay on 6 August. Designated Mark III, the egg-shaped weapon contained a 6.2 kilogram (14 pound) sphere of Plutonium Pu 239, surrounded by a high-explosive charge. The explosives were formed in “lenses” that would direct the force inward in a very precise manner. The purpose was to compress—or implode— the Plutonium to a much greater density, resulting in a “critical mass.”

The Mark III "Fat Man" bomb loaded on its carrier, 8 August 1945.
The Mark III “Fat Man” bomb being loaded onto its carrier, 8 August 1945.

In the conduct of this mission, Major Sweeney made a number of serious errors that nearly caused the mission to fail, and might very well have led to the loss of the bomber and its crew.

Prior to takeoff, the B-29’s crew chief informed Sweeney that a fuel transfer pump was inoperative which made it impossible to transfer 625 gallons (2,366 liters) of fuel from one fuel tank. This meant that nearly 9% of the total fuel load of 7,250 gallons (27,444 liters) was unusable. Chuck Sweeney decided to go anyway.

Next, though under direct orders from the 509th Composite Group commander, Colonel Paul Tibbets, to wait at the rendezvous no more than 15 minutes, when The Big Stink failed to arrive on schedule, Sweeney elected to stay 30 minutes beyond that.

Meanwhile, the two weather reconnaissance B-29s, Enola Gay and Laggin’ Dragon, were over Kokura, the primary target, and the secondary, Nagasaki. Weather over both cities were within the mission parameters.

XX Bomber Command Target Chart for Nagasaki Area. (National Archives)

During the 45 minutes that Sweeney waited at the rendezvous, weather over Kokura had deteriorated. By the time Bockscar arrived overhead, clouds covered the city. The bomber made three attempts to bomb the city over a 50-minute period, but the bombardier was not able to see the target.

Now an hour and twenty minutes behind schedule, Sweeney diverted to the secondary target, Nagasaki. Because of the delays and the unusable fuel as a result of the failed fuel pump, Sweeney reduced engine power to try to conserve fuel during the twenty minute flight to the alternate target. But weather there had also deteriorated.

Sweeney decided that they should bomb through the clouds using radar, but at the last minute, the bombardier was able to see the aim point. The Fat Man was dropped from 30,000 feet (9,144 meters) at 11:01 a.m. After falling for 43 seconds, the atomic bomb detonated at an altitude of 1,950 feet (594.4 meters). It missed the intended target point by nearly 1.5 miles (2.4 kilometers) and exploded over the Urakami Valley, halfway between the Mitsubishi Steel and Arms Works and the Mitsubishi-Urakami Ordnance Works.

Nagasaki, 9 August 1945, photographed by Joe Kosstatscher, U.S. Navy.
Nagasaki, 9 August 1945, photographed by Joe Kosstatscher, U.S. Navy.

The estimated force of the explosion was 21 kilotons—equivalent to the explosive force of 21,000 tons of TNT (19,050 metric tons)—nearly 20% greater than the Hiroshima bomb. The surrounding hills contained the explosion, protecting a large part of the city. Still, approximately 60% of Nagasaki was destroyed and 70,000 people were killed. By December 1945, at least 80,000 of the city’s 250,000 residents had died.

Atomic cloud rising over nagasaki, japan, 9 August 1945, photographed from Koyagi-jima. (Hiromichi Matsuda)
Pyrocumulus cloud rising over Nagasaki, Japan, approximately 20 minutes after detonation, 9 August 1945, photographed from Koyagi-jima, a small island southwest of Nagasaki. (Hiromichi Matsuda)

Now critically low on fuel and unable to reach the emergency B-29 recovery field on Iwo Jima, Sweeney headed for the airfields of Okinawa. When Bockscar touched down on the runway, one engine quit due to fuel starvation. As they turned off the runway, a second engine ran out of fuel. Charles Sweeney had cut it very, very close.

B-29 44-27297 on Tinian Island, August 1945. The nose art was applied to the airplane after the August 9, 1945 bombing mission. (U.S. Air Force)
Martin-Omaha B-29-35-MO 44-27297 on Tinian Island, August 1945. The nose art was applied to the airplane after the August 9, 1945 bombing mission. (U.S. Air Force)

Five days after the bombing of Nagasaki, the Emperor of Japan—recognizing that his country now faced total destruction—agreed to surrender. World War II was over.

In 1946, Bockscar was placed in storage at Davis-Monthan Army Air Field, Tucson, Arizona. On 26 September 1961, the B-29 was flown to the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Dayton, Ohio, where it remains in the museum’s collection of historic aircraft.

DAYTON, Ohio — Boeing B-29 Superfortress “Bockscar” at the National Museum of the United States Air Force. (U.S. Air Force photo)

© 2018, Bryan R. Swopes

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9 August 1944

MEDAL OF HONOR

LINDSEY, DARRELL R. (Air Mission)

Rank and organization: Captain, U.S. Army Air Corps.

Place and date: L’Isle Adam railroad bridge over the Seine in occupied France, 9 August 1944.

Entered service at: Storm Lake, lowa. Birth: Jefferson, lowa.

G.O. No: 43, 30 May 1945.

Medal of Honor
Medal of Honor

Citation: On 9 August 1944, Capt. Lindsey led a formation of 30 B-26 medium bombers in a hazardous mission to destroy the strategic enemy held L’lsle Adam railroad bridge over the Seine in occupied France. With most of the bridges over the Seine destroyed, the heavily fortified L’Isle Adam bridge was of inestimable value to the enemy in moving troops, supplies, and equipment to Paris. Capt. Lindsey was fully aware of the fierce resistance that would be encountered. Shortly after reaching enemy territory the formation was buffeted with heavy and accurate antiaircraft fire. By skillful evasive action, Capt. Lindsey was able to elude much of the enemy flak, but just before entering the bombing run his B-26 was peppered with holes. During the bombing run the enemy fire was even more intense, and Capt. Lindsey’s right engine received a direct hit and burst into flames. Despite the fact that his ship was hurled out of formation by the violence of the concussion, Capt. Lindsey brilliantly maneuvered back into the lead position without disrupting the flight. Fully aware that the gasoline tanks might explode at any moment, Capt. Lindsey gallantly elected to continue the perilous bombing run. With fire streaming from his right engine and his right wing half enveloped in flames, he led his formation over the target upon which the bombs were dropped with telling effect. Immediately after the objective was attacked, Capt. Lindsey gave the order for the crew to parachute from the doomed aircraft. With magnificent coolness and superb pilotage, and without regard for his own life, he held the swiftly descending airplane in a steady glide until the members of the crew could jump to safety. With the right wing completely enveloped in flames and an explosion of the gasoline tank imminent, Capt. Lindsey still remained unperturbed. The last man to leave the stricken plane was the bombardier, who offered to lower the wheels so that Capt. Lindsey might escape from the nose. Realizing that this might throw the aircraft into an uncontrollable spin and jeopardize the bombardier’s chances to escape, Capt. Lindsey refused the offer. Immediately after the bombardier had bailed out, and before Capt. Lindsey was able to follow, the right gasoline tank exploded. The aircraft sheathed in fire, went into a steep dive and was seen to explode as it crashed. All who are living today from this plane owe their lives to the fact that Capt. Lindsey remained cool and showed supreme courage in this emergency.

Strike photo, L’Isle-Adam Railroad Bridge, 9 August 1944. (U.S. Air Force)

Darrell Robbins Lindsey was born 30 December 1919 at Jefferson, Iowa. He was the second of two sons of Jesse Lyle Lindsey, a civil engineer, and Grace Alice Puffer Lindsey. Darrell Lindsey grew up in Iowa, where he attended Fort Dodge High School, graduating in 1938. He then studied at Buena Vista College at Storm Lake, before transferring to Drake University in Des Moines.

Aviation Cadet Darrell Robbins Lindsey, circa 1942.

Immediately following the United States’ entry into World War II, 16 January 1942, Lindsey enlisted as an aviation cadet in the U.S. Army Air Corps. He trained as a pilot and on graduating from flight school, was commissioned as a second lieutenant, 27 August 1942.

Lieutenant and Mrs. Darrell R. Lindsey, circa 1942.

Following his commissioning, Lieutenant Lindsey married Miss Evelyn Scott of Storm Lake, Iowa.

Lieutenant Lindsey next trained as a bombardier at Kirtland Field, New Mexico. He was promoted to first lieutenant and was assigned to a Martin B-26 Marauder operational training unit, the 314th Bombardment Squadron (Medium), at MacDill Army Airfield, near Tampa, Florida. He was promoted to captain in December 1943.

Captain Lindsey was assigned to the 585th Bombardment Squadron (Medium), 394th Bombardment Group (Medium), as a B-26 aircraft commander and flight leader. The unit deployed to Europe in February 1944. The 585th was initially stationed at RAF Boreham (AAF-161) in Essex, but in July 1944, moved to RAF Holmsley South (AAF-455), Hampshire, England.

The bombing mission against the L’Isle-Adam Railroad Bridge on 9 August 1944 was Captain Lindsey’s 46th combat mission. Army Air Corps records indicate that at the time of his death, he had flown a total of 1,497:00 hours. 143 hours were in combat.

Captain Lindsey’s remains were buried at an unknown location. In 1959, a cenotaph memorializing Captain Lindsey was placed at Jefferson Cemetery, Jefferson, Iowa.

The Medal of Honor was presented to Captain Lindsey’s widow, Mrs. Evelyn Scott Lindsey, 9 August 1945, by Major General Robert B. Williams, commanding Second Air Force. In November 1946, Lindsey Air Station at Wiesbaden, Germany, was named in his honor.

In addition to the Medal of Honor, Captain Lindsey was awarded the Distinguished Flying Cross, the Air Medal with eight oak leaf clusters (nine awards), and the Purple Heart.

Martin B-26B-55-MA Marauder 42-96153 of the 397th Bombardment Group (Medium), at Peronne Advanced Landing Ground (A-72), France, January 1945. This is the same type as the B-26 flown by Captain Darrell R. Lindsey, 9 August 1944. (U.S. Air Force)

Captain Lindsey’s B-26 was a Glenn L. Martin Company B-26B-55-MA Marauder, serial number 42-96101, built at Baltimore, Maryland. It carried the squadron identification markings 4T N on its fuselage.

The Martin B-26 first flew 25 November 1940. The B-26 was a twin-engine medium bomber designed with high speed as a primary objective. Production of the new airplane was considered so urgent that there were no prototypes. All aircraft were production models.

Martin B-26B-55-MA Marauder 42-96142, 596th Bombardment Squadron (Medium), 397th Bombardment Group (Medium). This is the same type aircraft flown by Captain Lindsey in the attack against the L’Isle-Adam Railroad Bridge. (U.S. Air Force)

The B-26B was 58 feet, 3 inches (17.755 meters) long with a wingspan of 71 feet, 0 inches (21.641 meters) and overall height of 21 feet, 6 inches (6.533 meters). It had an empty weight of 24,000 pounds (10,886 kilograms) and gross weight of 37,000 pounds (16,783 kilograms).

The B-26B-55-MA was powered by two air-cooled, supercharged, 2,804.461-cubic-inch-displacement (45.956 liter), Pratt & Whitney Double Wasp 2SB-G (R-2800-43) two-row, 18-cylinder radial engines with a compression ratio of 6.65:1. The R-2800-43 had a Normal Power rating of 1,600 horsepower at 2,400 r.p.m. to 5,700 feet (1,737 meters), 1,450 horsepower at 2,400 r.p.m. at 13,000 feet (3,962 meters). Its Takeoff Power rating was 2,000 horsepower at 2,700 r.p.m. The Military Power rating was the same as Takeoff Power up to 2,700 feet (823 meters), and 1,600 horsepower at 2,700 r.p.m. to 13,500 feet (4,115 meters). They turned 13 foot, 6 inch (4.115 meter) diameter four-bladed Curtiss Electric propellers through a 2:1 gear reduction. The R-2800-43 was 6 feet, 3.72 inches (1.923 meters) long, 4 feet, 4.50 inches (1.334 meters) in diameter, and weighed 2,300 pounds (1,043 kilograms). All R-2800-43 engines were built by the Ford Motor Company.

The B-26B had a maximum speed of 270 miles per hour (435 kilometers per hour) at Sea Level, and 282 miles per hour (454 kilometers per hour) at 15,000 feet (4,572 meters). The airplane’s service ceiling was 21,700 feet (6,614 meters). It’s maximum ferry range was 2,850 miles (4,587 kilometers).

The B-26B was armed with 11 air-cooled Browning AN-M2 .50-caliber machine guns. One was at the nose on a flexible mount, two fixed guns were on each side of the fuselage in “blister packs,” there were two flexible guns in the waist. A power-operated dorsal gun turret had two, as did the tail turret.

A maximum of four 2,000 pound (907 kilograms) bombs could be carried in the bomb bay.

Martin B-26F-1-MA of the 397th Bomb Group in flight at bomb release. (U.S. Air Force)

When the B-26 entered service, it quickly gained a reputation as a dangerous airplane and was called “the widowmaker.” The airplane had relatively short wings with a small area for its size. This required that landing approaches be flown at much higher speeds than was normal practice. With one engine out, airspeed was even more critical. Some changes were made, such as a slight increase on wingspan and the size of the vertical fin and rudder, and an emphasis was made on airspeed control during training. The Marauder had the lowest rate of combat losses of any American bomber.

The Glenn L. Martin Co. produced 5,288 Marauders between 1941–1945. It served in the Pacific, Mediterranean and European combat areas. When it was removed from service at the end of World War II, the “B-26” designation was reassigned to the Douglas A-26 Invader, a light twin-engine bomber.

© 2017, Bryan R. Swopes

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8 August 1945

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, 8 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, ± inch

© 2017, Bryan R. Swopes

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