A North American Aviation B-25B Mitchell medium bomber revs its engines, awaiting the signal to launch from the flight deck officer. (U.S. Navy)With flight deck personnel dropping to the deck to avoid its turning propellers, a North American B-25B Mitchell medium bomber starts its takeoff roll aboard USS Hornet (CV-8), 18 April 1942. (U.S. Navy)Fleet Admiral William F. Halsey, United States Navy
18 April 1942: Task Force 16, under the command of Vice Admiral William F. Halsey, Jr., U.S. Navy, approached the Japanese islands on a daring top secret joint Army-Navy attack.
Planning for the attack began in January 1942 under orders from Admiral Earnest J. King, Commander-in-Chief United States Fleet. Captain Donald B. Duncan, U.S. Navy, was responsible for the plan.
The operation was carried out by Task Force 16 under the command of Vice Admiral William F. Halsey, Jr., United States Navy. Task Force 16 consisted of two aircraft carriers, USS Enterprise (CV-6) and USS Hornet (CV-8), four cruisers, eight destroyers and two oilers. There were two air groups, consisting of eight squadrons of 54 fighters, 72 dive bombers, 36 torpedo bombers, and one squadron of of 16 medium bombers. Lieutenant Colonel James Harold (“Jimmy”) Doolittle, U.S. Army Air Corps, commanded the Strike Group of North American Aviation B-25 Mitchell bombers aboard Hornet.
With the land-based Army bombers secured to Hornet‘s flight deck, her own fighters had been struck below. The air group from Enterprise provided Combat Air Patrol for the task force. The plan was to bring the B-25s within 400 miles (645 kilometers) of Japan, have them take off and carry out the attack, then fly on to airfields in Chinese territory.
A U.S. Army Air Corps B-25B Mitchell medium bomber is launched from USS Hornet (CV-8), 18 April 1942. (U.S. Navy)Lieutenant Colonel James H. (“Jimmy”) Doolittle, U.S. Army Air Corps, flies a North American Aviation B-25B Mitchell medium bomber off the deck of USS Hornet (CV-8), 18 April 1942. His was the first bomber to takeoff. (U.S. Navy)
At 0500 hours, the task force was sighted by a Japanese picket boat while still over 700 miles (1,127 kilometers) away from Tokyo. At 0644 another vessel was spotted by the task force. Fearing that surprise had been lost, Admiral Halsey ordered the bombers launched while still 623 miles (1,003 kilometers) from land.
A North American Aviation B-25B Mitchell medium bomber takes off from USS Hornet (CV-8). The airplane’s nose wheel has lifted clear of the flight deck while the ship’s bow pitches down in heavy seas. (U.S. Navy)Lt. Col. James H. Doolittle, USAAC, aboard USS Hornet, April 1942. (U. S. Air Force)
The sixteen B-25s were successfully launched from Hornet and headed for their assigned targets. The lead airplane, B-25B serial number 40-2344, was flown by Lieutenant Colonel Doolittle.
Single B-25s attacked targets in the cities of Tokyo, Nagoya, Osaka and Kobe.The first bombs were dropped on Tokyo at 1215 local time. This was the first offensive operation carried out by the United States of American against the Empire of Japan during World War II.
The actual destructive effect of the attack was minimal. It had been hoped that there would be psychological effects on the citizenry, however the arrival of the American bombers coincided with an ongoing air raid drill, and many thought it was all part of the drill.
Militarily, however, the attack was a stunning success. Four Japanese fighter groups, needed elsewhere, were pinned down at home, waiting for the next attack.
A B-25 is airborne over the bow of USS Hornet (CV-8). (U.S. Navy)
Not a single B-25 was lost over Japan. One landed in Vladivostok where the crew and airplane were interred by the “neutral” Soviets, but they eventually were able to get home. The rest continued on toward China, though without enough fuel to reach their planned destinations. Four B-25s made crash landings, but the crews of the others bailed out into darkness as their planes ran out of gas.
Routes of ten of the sixteen B-25s. Lieutenant Colonel Doolittle’s airplane, 40-2344, enters the chart at the upper right corner, the exits to upper left. (United States Army)Yokosuka Naval Base photographed from an American B-25 bomber, 18 April 1942. (National Archives and Records Administration, 342-FH-#A-3028-9302)The wreckage of Jimmy Doolittle’s North American Aviation B-25B Mitchell bomber, 40-2344, China, April 1942. (Smithsonian.com)Lieutenant Colonel James Harold Doolittle (just right of center) with his crew in China following the 18 April 1942 air raid on Japan. Left to right, Staff Sergeant Fred A. Braemer; Staff Sergeant Paul J. Leonard; Lieutenant Richard E. Cole; Lieutenant Colonel Doolittle; and Lieutenant Henry A. Potter. (United States Navy, Naval History and Heritage Command NH 97502)
Five of the airmen were killed. Eight were captured by the Japanese, two of whom were executed by a military court, and another died in prison.
Captain Edward J. York’s North American Aviation B-25B Mitchell, 40-2242, Aircraft 8, interned about 40 miles (25 miles) west of Vladivostok, Primorsky Krai, Union of Soviet Socialist Republics.1st Lieutenant Robert L. Hite, USAAC, co-pilot of Aircraft 16, “Bat Out of Hell,” was captured by the Japanese after bailing out over China, and was held as a prisoner of war for 3½ years. (U.S. Air Force)
For his leadership in the air raid, James Harold Doolittle was promoted to the rank of Brigadier General, and was awarded the Medal of Honor by President Franklin D. Roosevelt. General Doolittle’s Medal is in the collection of the National Air and Space Museum.
President Franklin D. Roosevelt presents the Medal of Honor to Brigadier General James Harold Doolittle in a ceremony at The White House, 19 May 1942. The President is seated at left. Standing, left to right, are Lieutenant General Henry H. Arnold, Chief of the Army Air Forces; Mrs. Doolittle; Brigadier General Doolittle; and General George Catlett Marshall, Jr., Chief of Staff, United States Army. (Franklin D. Roosevelt Library and Museum, Photographic Collection, NPx. 65-696)
CITATION:
The President of the United States of America, in the name of Congress, takes pleasure in presenting the Medal of Honor to Brigadier General [then Lieutenant Colonel] James Harold Doolittle (ASN: 0-271855), United States Army Air Forces, for conspicuous leadership above the call of duty, involving personal valor and intrepidity at an extreme hazard to life while Commanding the First Special Aviation Project in a bombing raid of Tokyo, Japan, on 18 April 1942. With the apparent certainty of being forced to land in enemy territory or to perish at sea, General Doolittle personally led a squadron of Army bombers, manned by volunteer crews, in a highly destructive raid on the Japanese mainland.
War Department, General Orders No. 29 (June 9, 1942), Amended by Department of the Army G.O. No. 22 (1959) & No. 4 (1960)
The Medal of Honor awarded to Brigadier General James Harold Doolittle, Air Corps, United States Army, in the collection of the Smithsonian Institution National Air and Space Museum, (NASM A19600049000)
General Dynamics F-111F Aardvark with 2000 pound GBU-10 Paveway II laser-guided bombs at RAF Lakenheath, 14 April 1981. (U.S. Air Force)
14 April 1986: In response to several acts of international terrorism sponsored by the Libyan regime of Muammar Khadafi, the United States launched Operation El Dorado Canyon. Along with A-6E Intruders, F/A-18 Hornets and A-7 Corsair IIs from the aircraft carriers USS America and USS Coral Sea, 24 General Dynamics F-111F Aardvarks of the 48th Tactical Fighter Wing from RAF Lakenheath, accompanied by EF-111 Ravens for electronic counter measures, and flew 3,500 miles to their targets.
Navy aircraft attacked Benina Airfield and the Benghazi barracks, while the Air force fighter bombers, using GBU-10 Paveway II 2,000-pound laser-guided bombs, attacked the Aziziyah Barracks and the Sadi Bilal terrorist training camp at Tripoli. Because of the length of the flight, the F-111s had to refuel from KC-10 Extender air tankers four times in each direction. The KC-10s, in turn, refueled in flight from KC-135 Stratotankers.
There were very stringent rules of engagement in place, and for that reason, the majority of the Aardvarks did not release their bombs.
Libya had some of the most sophisticated air defenses in the world. Analysis indicated that only three cities in Russia were more heavily defended. Even so, of the 55 aircraft in the two attack forces, only one F-111 was lost, probably shot down by a surface-to-air missile. Its two man crew were killed.
A number of Libyan aircraft and facilities were destroyed. 37 people were killed and 93 wounded. From the standpoint of destruction caused, the results were minimal. But the effects on Colonel Khadafi were pronounced, and resulted in a significant scaling back of his regime’s terrorist activities. Viewed from that perspective, the mission was a complete success.
General Dynamics F-111F 70-2380, 48th Tactical Fighter Wing, with wings swept for high-speed flight, over a desert landscape. (U.S. Air Force)
Operation Teapot HA fireball, 6 April 1955. (U.S. Air Force)
6 April 1955: At 10:00:04.1 a.m. local time (1800 GMT), a Convair B-36H assigned to the 4925th Test Group (Atomic) at Kirtland Air Force Base, New Mexico dropped an atomic weapon from 42,000 feet (12,802 meters) over the Nevada Test Site, Area 1. The bomb was parachute-retarded to slow its fall so that the bomber could escape its blast effects.
The weapon was a test device produced by the Los Alamos Scientific Laboratory to investigate its use as an air-to-air anti-aircraft missile warhead. The bomb detonated at 36,620 feet (11,162 meters) with an explosive force of 3.2 kilotons. Because of the altitude of the explosion, there was no significant fallout.
All test observers (with goggles) agreed that the fireball appeared more intensely bright than in events of similar yield fired at lower altitude.
—United States High-Altitude Test Experiences by Herman Hoerlin, Los Alamos Scientific Laboratory, June 1976, at Page 12.
Captain William L. Hickey, USAF, pilot of a Convair B-36 Peacemaker very long-range heavy bomber during Operation Teapot, 1955. Captain Hickey is wearing a David Clark Co. S-2 capstan-type partial-pressure suit and K-1 helmet for protection at high altitude. (Jet Pilot Overseas)
The warhead was designed at the Los Alamos Scientific Laboratory (LASL) in New Mexico and was similar to the Wasp Prime device, which had been detonated earlier in the Operation Teapot test series. It used a spherical implosion device. The warhead was a 17-inch (43.2 centimeters) diameter sphere weighing approximately 125 pounds (56.7 kilograms). It was placed inside a Mark 5 bomb case which weighed 1,085 pounds (492.2 kilograms).
This was the only bomb dropped by parachute at the Nevada Test Site.
Flight crew of a Convair B-36 Peacemaker, 4925th Test Group (Atomic) during Operation Teapot, 1955. The crewmen are wearing David Clark Co. S-2 capstan-type partial-pressure suits for protection at high altitude. The two white helmets are early K-1 “split shell” two-piece helmets, while the green helmets are later K-1 one-piece models. (Jet Pilot Overseas)
The Convair B-36H Peacemaker was the definitive version of the ten engine bomber, with 156 B-36H/RB-36H built out of the total production of 383 Peacemakers. It is similar to the previous B-36F variant, though with a second flight engineer’s position, a revised crew compartment, and improved radar controlling the two 20 mm autocannons in the tail turret.
The B-36H was 162 feet, 1 inch (49.403 meters) long with a wingspan of 230 feet (70.104 meters) and overall height of 46 feet, 8 inches (14.224 meters). The total area of its wings was 4,772 square feet (443.3 square meters). The wings’ leading edges were swept aft 15° 5′ 39″. Their angle of incidence was 3°, with -2° twist and 2° dihedral. The empty weight of the B-36H was 165,887pounds (75,245 kilograms) and the maximum takeoff weight is 357,500 pounds (162,159 kilograms).
Three flight crewmen don their parachutes before boarding the B-36H Peacemaker for Operation Teapot HA, 5 April 1955. The automobile behind them is a 1955 Chevrolet Bel Air 4-door sedan. (U.S. Air Force)
The B-36H has ten engines. There are six air-cooled, supercharged 4,362.49 cubic-inch-displacement (71.49 liter) Pratt & Whitney Wasp Major C6 (R-4360-53) four-row, 28-cylinder radial engines placed inside the wings in a pusher configuration. These had a compression ratio of 6.7:1 and required 115/145 aviation gasoline. The R-4360-53 had a Normal Power rating of 2,800 horsepower at 2,600 r.p.m. Its Military Power rating was 3,500 horsepower at 2,800 r.p.m., and 3,800 horsepower at 2,800 r.p.m. with water injection—the same for Takeoff. The engines turned three-bladed Curtiss Electric constant-speed, reversible propellers with a diameter of 19 feet, 0 inches (5.791 meters) through a 0.375:1 gear reduction. The R-4360-53 is 9 feet, 9.00 inches (2.972 meters) long, 4 feet, 7.00 inches (1.397 meters) in diameter, and weighs 4,040 pounds (1,832.5 kilograms).
A smoke ring formed following the detonation of the Operation Teapot HA test. Contrails of the test aircraft are visible. (U.S. Air Force)
Four General Electric J47-GE-19 turbojet engines are suspended under the wings in two-engine pods. The J47 is a single-shaft axial-flow turbojet engine with a 12-stage compressor section, 8 combustion chambers, and single-stage turbine. The J47-GE-19 was modified to run on gasoline and was rated at 5,200 pounds of thrust (23.131 kilonewtons).
The B-36H was the fastest variant of the Peacemaker series, with a cruise speed of 216 knots (249 miles per hour/400 kilometers per hour) and a maximum speed of 382 knots (440 miles per hour/707 kilometers per hour) at 35,500 feet (10,820 meters). The service ceiling was 47,000 feet (14,326 meters) and its combat radius was 3,190 nautical miles (3,671 statute miles/5,908 kilometers). The ferry range was 7,120 nautical miles (8,194 statute miles/13,186 kilometers).
Convair RB-36H-40-CF 51-13741 Featherweight III. (U.S. Air Force)
The B-36H has six remotely-controlled retractable gun turrets mounting two M24A1 20 mm autocannon, each, with 600 rounds of ammunition per gun. The tail turret was radar-controlled, and another 2 guns were mounted in the nose.
The B-36 was designed during World War II, when nuclear weapons were unknown to the manufacturer. The bomber was built to carry up to 86,000 pounds (39,009 kilograms) of conventional bombs in fours bomb bays. It could carry two 43,000 pound ( kilogram) T-12 Cloudmakers, a conventional explosive earth-penetrating bomb, or several Mk.15 thermonuclear bombs. By combining the bomb bays, one Mk.17 25-megaton thermonuclear bomb could be carried.
This Convair RB-36D-5-CF, 49-2686, is similar in appearance to the B-36H used in Operation Teapot HA. (U.S. Air Force)
Martin XB-51 46-685, the number one prototype, on takeoff. (Lockheed Martin)
25 March 1956: At approximately 10:50 a.m., the first of two prototype Martin XB-51 three-engine attack bombers, serial number 46-685, crashed on takeoff from Runway 22 at El Paso International Airport (ELP). The pilot, Major James Otto Rudolph, United States Air Force, survived the crash although he was seriously burned. Staff Sergeant Wilbur Robert Savage, 28, engineer, was killed. Major Rudolph died of injuries 16 April 1956.
Pieces of wreckage were marked “Gilbert XF-120” which had been painted on the airplane for the filming of the William Holden, Lloyd Nolan movie, “Toward The Unknown.” (Toluca Productions, 1956). The second prototype, 46-686, had previously crashed at Edwards AFB.
A newspaper article from the El Paso Times is quoted below [I have corrected some typographical errors]:
03/26/1956
Bill Feather El Paso Times
A sleek jet bomber, carrying a full load of fuel, crashed while attempting a take-off at International Airport Sunday morning, killing the flight engineer and seriously injuring the pilot.
The XB-51, the only one of its type in existence, smashed through the fence at the end of the southwest runway and then began to disintegrate, spreading wreckage along a 250-yard trail.
Only the tail section of the three-engine bomber was left intact.
Name of the dead man, a 28-year-old staff sergeant was withheld pending notification of next of kin.
Flying the aircraft was Maj. James O. Rudolph, 36, one of the top test pilots in the Air Force.
He suffered severe burns and was taken Sunday afternoon in an emergency flight to Brooke Army Hospital in San Antonio.
The XB-51, based at Edwards Air Force Base in Muroc, Calif., was being flown to Eglin Air Force Base, Florida, where it was to be used in the filming of a Warner Brothers movie, “Toward the Unknown.”
Identification of the aircraft was confused for a short time after the crash.
A piece of wreckage with the notation “Gilbert XF-120” was found nearby.
HAD REFUELED
Air Force spokesmen explained that the XF designation had been painted on the plane for use in the movie.
The airplane had been refueled at International Airport and started its takeoff at 10:30 a.m.
Witnesses said the plane got about three feet above the ground and suddenly settled. The tail dragged first and then the rest of the airplane settled, running at high speed.
It ripped through a barbed wire fence at the end of the runway, raced across Airport Road and then began to go to pieces.
After crashing, it burned and several explosions threatened firemen, rescuers and spectators who crowded around the flaming aircraft.
First person to the scene of the crash was Eddie C. Wilkerson, 1106 Del Monte Drive, tennis coach at Austin High School.
“I was just turning into the road to the airport when the plane was taking off. I don’t believe it ever got airborne.
“I looked back and saw a big ball of smoke, so I just wheeled my car around.”
Wilkerson said that when he arrived, the major was lying on the ground about 15 feet from the burning wreckage.
“His clothes were burning so I started tearing them off.”
Other witnesses to the crash arrived and helped Wilkerson move the major to a safer place, away from the intense heat of the flaming aircraft.
Capt. John D. Chandler, a doctor at the Biggs Hospital, was at the airport when the crash occurred and he was one of the first persons at the scene. He administered aid to the injured man until an ambulance arrived. Later Capt. Chandler flew to San Antonio with Maj. Rudolph.
A fire truck from International Airport was rushed to the scene almost as soon as the plane stopped its forward motion.
Sunday drivers were attracted to the scene by the tower of smoke and the heavy traffic delayed the arrival of fire trucks from Biggs Air Force Base.
The plane was one of two XB-51s built by Martin Aircraft Co. and was completed in 1953.
The first one crashed at Muroc, Calif., in 1952.
Air Force spokesmen said the aircraft was comparable to the B-47, which was accepted instead of the XB-51 for use in the Air Force.
Its three jet engines one in each wing and on in the fuselage, were capable of driving the craft at tremendous speeds. The aircraft had broken the sound barrier, spokesmen said.
Its sleek lines gave it the appearance of a fighter rather than a medium bomber.
Normally, the airplane carried a crew of three.
Recently it had been used in assisting the Army in missile and anti-aircraft development at Aberdeen Proving Ground, Md.
A board of officers was investigation the crash and two Air Force colonels arrived at Biggs Air Force Base from Muroc Sunday afternoon.
Military police from Ft. Bliss and Air Police patrolled the area about the crash Sunday afternoon, keeping away the curious.
James Otto Rudolph was born at Marion, Ohio, 8 February 1920, the first of two children of of Frank Otto Rudolph, a German immigrant who was employed as a secretary for the YMCA, and Helen Claire Shafer Rudolph.
Following two years of college, Rudolph enlisted as an Aviation Cadet, U.S. Army Air Corps, at Detroit, Michigan, 17 March 1941. He was 6 feet, 1inch (1.854 meters) tall and weighed 175 pounds (79.4 kilograms). He was commissioned as a Second Lieutenant, Air Reserve, 31 October 1941,and was promoted to First Lieutenant, Army of the United States (Air Corps), 5 August 1942. He was again promoted, to Captain, 15 June 1943. Following the end of World War II, Rudolph was promoted to the rank of Major, 19 September 1946. He remained in the Air Force, but with military needs shrinking, he reverted to the rank of First Lieutenant, with date of rank, 7 December 1944.
James Rudolph married Clara D. in 194–
Major Rudolph graduated from the U.S. Air Force Experimental Flight Test Pilot School, Class 54-A, 2 July 1954. As a test pilot at Edwards Air Force Base, Rudolph was a project pilot in the FICON program in which Republic RF-84K Thunderflash reconnaissance planes were carried by modified Convair RB-36D bombers.
During his military career, Major Rudolph had been awarded the Air Medal with three oak leaf clusters (four awards).
After the crash on 25 March 1956, Major Rudolph was taken to Brooke Army Hospital, Fort Sam Houston, Texas, suffering from 2nd and 3rd degree burns over 38% of his body. He contracted septicemia and died there, 16 April 1956. He is buried at Arlington National Cemetery.
Wilbur Robert Savage was born 19 July 1927 at Dawsonville, Georgia. He was the son of Newton McKinley Savage and May Belle Carney Savage. He married to Ida Pedroza Aceves in 1948. They would have three children.
Staff Sergeant Savage’s remains were interred at Mountain View Cemetery, San Bernardino, California.
The first Martin XB-51, 46-585, in flight. (U.S. Air Force)
The Glenn L. Martin Co. XB-51 was a prototype jet-powered ground attack bomber. It was an unusual design for its time. The airplane had mid-mounted, variable-incidence swept wing, a T-tail and tandem landing gear with a configuration similar to that used on the Boeing B-47 Stratojet (and which had been tested using a Martin B-26 Marauder medium bomber.)
The XB-51 was operated by a pilot in a single-place cockpit with a bubble canopy, and a navigator station inside the fuselage, below and behind the pilot. The prototype was 85 feet, 1 inch (25.933 meters) long with a wingspan of 53 feet, 1 inch (16.180 meters) and overall height of 17 feet, 4 inches (5.283 meters). The total wing area was 548.0 square feet (50.9 square meters). The airplane had an empty weight of 30,906 pounds (14,019 kilograms) and a maximum overload takeoff weight of 62,452 pounds (28,328 kilograms).
The wings of the XB-51 were swept aft to 35° and had 6° anhedral. The wings’ angle of incidence (the relation of the chord to the fuselage longitudinal axis) could be adjusted to increase lift for takeoff and landing. They had 2° negative twist and were equipped with leading edge slats for improved low speed performance. Instead of ailerons, the XB-51 used spoilers.
Lloyd Nolan (“General Bill Banner”) and William Holden (“Major Lincoln Bond”) with the “Gilbert XF-120” in the 1956 Hollywood movie, “Toward the Unknown.” (Toluca Productions via Turner Classic Movies)
Power was supplied by three General Electric J47-GE-13 turbojet engines, with two located in nacelles outboard of the forward fuselage on 45° pylons, and a third installed in the tail with its intake on top of the fuselage. The J47-GE-13 was an axial-flow turbojet with a 12-stage compressor and single stage turbine. It had a normal power rating of 4,320 pounds of thrust (19.216 kilonewtons) at 7,370 r.p.m.; military power, 5,200 pounds (23.131 kilonewtons) at 7,950 r.p.m. (30-minute limit); and maximum power rating of 6,000 pounds(26.689 kilonewtons) at 7,950 r.p.m., with water/alcohol injection (5-minute limit). The engine was 12 feet, 0.0 inches (3.658 meters) long, 3 feet, 3.0 inches (0.991 meters) in diameter and weighed 2,525 pounds (1,145 kilograms). A Rocket Assisted Takeoff (RATO) system was also installed.
The XB-51 had a maximum speed of 560 knots (644 miles per hour/1,037 kilometers per hour) at Sea Level—0.85 Mach. The service ceiling was 39,400 feet (12,009 meters) and the maximum ferry range was 1,255 nautical miles (1,444 statute miles/2,324 kilometers).
Armament was planned for a maximum bomb load of 10,400 pounds (4,717 kilograms) carried internally in a rotary bomb bay, and eight M39 20 mm revolving autocannon mounted in the nose with 160 rounds of ammunition per gun. 5-inch High Velocity Aerial Rockets (HVAR) could be carried under the wings or in the bomb bay.
Martin XB-51 46-685 during engine start and ground run-up. (U.S. Air Force)
19 March 1945: Modified Avro Lancaster B Mk.I Special heavy bombers of No. 617 Squadron, Royal Air Force, attacked the railway viaduct at Arnsberg, Germany, using the 22,000 pound (9,979 kilogram) Grand Slam earth-penetrating bomb. The bomb had been first used just days before, 14 March, against another railway viaduct.
The Grand Slam was the largest and heaviest aerial bomb used during World War II. It was designed by aircraft engineer Barnes Neville Wallis, and was scaled up from his earlier, smaller “Tallboy.” (Wallis also designed the “Upkeep” Special Mine used to attack hydroelectric dams in the Ruhr Valley in 1943.)
Wallis’ idea was that a very heavy, supersonic bomb could penetrate deep into the earth and detonate, causing an “earthquake” which could destroy nearby heavily protected targets.
Tall Boy and Grand Slam Deep Penetration Bombs (British Explosive Ordnance, Part 1, Chapter 7)
The Grand Slam bomb (officially, “Bomb, D.P., 22,000-lb., Mk I”) was 25 feet, 5 inches (7.747 meters) long and had a maximum diameter of 3 feet, 10 inches (1.168 meters). When fully loaded with the explosive material, Torpex, the bomb weighed 22,400 pounds (10,160 kilograms).
Completed bomb casings for Wallis’ smaller 12,000-pound “Tallboy” deep penetration bomb. The individual weight is stenciled on each casing. (Tyne & Wear Archives)
The bomb case was cast of steel at the Clyde Alloy and Steel Company, Glasgow, Scotland, then, after several days of cooling, machined to its precise shape. The casing made up approximately 60% of the bomb’s total weight. At the nose, the casing had a wall thickness of 7.75 inches (19.685 centimeters).
The bomb case was filled with approximately 9,200 pounds (4,173 kilograms) of molten Torpex, with a 1 inch (2.54 centimeters) topping of TNT. Torpex was an explosive designed for torpedo warheads and depth charges. It was made up of approximately equal quantities of two other explosives, Research Department Formula X (RDX), 42%, and trinitrotoluol (TNT), 40%, mixed with 18% powdered aluminum and wax. The resulting combination was approximately 1.4 times more powerful than TNT alone. About one month was required for the explosive to cool after being poured into the bomb case.
Because of its size and weight, the only Allied bomber capable of carrying the Grand Slam was a specially modified Avro Lancaster B.I Special, flown by No. 617 Squadron, Royal Air Force, “The Dambusters.”
An Avro Lancaster very long range heavy bomber carrying a Gland Slam bomb. (Royal Air Force via Sierra Hotel Aeronautics)
Wallis intended for the Grand Slam to be dropped from very high altitudes so that during its fall, it would go supersonic. The bomb had large fins that were offset 5° to the right of the centerline to cause it to rotate for stability. However, the bombers could not carry it to the planned release altitude, and it was typically dropped from approximately 9,000 feet (2,743 meters). Its very sleek design did allow it to come close to the speed of sound, however, and its stability made it a very accurate weapon. The bomb was capable of penetrating 20-foot-thick (6 meters) reinforced concrete roofs of submarine bases. ¹
Arnsberg railway viaduct following Grand Slam bombing attack.
Barnes Neville Wallis, Esq., M. Inst. C.E., F.R.Ae.S., Assistant Chief Designer Vickers-Armstrongs Ltd., was appointed Commander of the Most Excellent Order of the British Empire (Civil Division), by His Majesty, King George VI, 2 June 1943.
Sir Barnes Neville Wallis C.B.E., was knighted by Her Majesty, Queen Elizabeth II, 13 December 1968.
Sir Barnes Neville Wallis C.B.E.
¹ “The striking velocity of the bomb, when released at an altitude of 16,000 ft. and an air speed of 200 m.p.h., is stated at 1,097 ft./sec., at which speed it has developed a rotational velocity of 60 r.p.m.” —British Explosive Ordnance, Part 1, Chapter 7
