B-36B 44-92075
Encyclopedia
On February 13, 1950, a Convair B-36B
, serial number 44-92075 assigned to the 7th Bomb Wing at Carswell Air Force Base
, crashed in northern British Columbia
after jettisoning a Mark IV
atomic bomb. This was the first such nuclear weapon loss
in history. The Convair had been en route from Eielson Air Force Base
near Fairbanks, Alaska
to Carswell AFB in Fort Worth, Texas
, on a mission that included a simulated nuclear attack on San Francisco, California
.
. Each B-36 involved in this exercise was to conduct a simulated nuclear attack on an American city. The exercise was also intended to test whether the B-36 could attack the Soviet Union
during the Arctic winter, when temperatures are so low that if a plane engine were shut down while a plane was being serviced on the ground, the engine could not be restarted.
Plane 44-92075 took off from Eielson AFB with a crew of 16 plus one observer. The plan for the 24-hour flight was to fly over the North Pacific, due west of the Alaska panhandle
and British Columbia
, then head inland over Washington state and Montana
. The flight plan did not include any penetration of Canadian airspace
. The plane carried a Mark IV
atomic bomb, containing a substantial quantity of natural uranium
and 500 pounds of conventional explosives. According to the USAF, the bomb did not contain the plutonium core necessary for a nuclear detonation.
Cold weather (-40F on the ground at Eielson AFB) adversely affected the planes involved in this exercise, and some minor difficulties with 44-92075 were noted before takeoff. Seven hours into the flight, three of the six engines began shooting flames and were shut down, and the other three engines proved incapable of delivering full power. The subsequent investigation blamed ice buildup
in the mixture control
air intakes.
The crew decided to abandon the aircraft because it could not stay aloft with three engines out of commission while carrying a heavy payload. The atomic bomb was jettisoned and detonated in mid-air, resulting in a large conventional explosion over the Pacific. The USAF later stated that the fake practice core on board the aircraft was inserted into the weapon before it was dropped.
The aircraft commander steered the plane over Princess Royal Island
to spare his crew having to parachute into the cold North Pacific, whereupon the crew bailed out. Before bailing out last, the he set a turning course toward the open ocean using the autopilot
.
The plane had been in constant radio contact with the Strategic Air Command
and within minutes of the bailout the Royal Canadian Air Force
launched Operation Brix to find the missing men. Poor weather hampered search efforts; nevertheless 12 of the 17 men were eventually found alive. The five deceased airmen were believed to have bailed out of the aircraft earlier than the surviving crew members, and it was assumed that they landed in the ocean and drowned. Canadian authorities were never told that the aircraft was carrying a nuclear weapon.
aircraft of Texas millionaire oilman Ellis Hall spotted the B-36's wreckage. It was nearly completely intact, on the side of Mount Kologet, about 50 miles (80.5 km) from the Alaskan border, roughly due east of the towns of Stewart, BC
and Hyder, AK
, on the east side of the isolated Nass
Basin northwest of Hazelton, British Columbia
.
The USAF immediately began an investigation. A team was sent in September 1953 but the effort was not given a high priority. After 19 days of trudging through the wilderness, they failed to reach the site. The effort was resumed the following year with better equipment, and in August 1954 a new team of USAF personnel accompanied by a local guide reached the wreckage. They recovered important components and then used explosives to destroy what was visible above the snow. The American and Canadian military kept the location of the wreck secret, though the operation had been run openly and the general details were known to the public. Curiously, when the American military first released information about the crash decades later, the documents falsely stated that the wreck had been found on distant Vancouver Island
.
In 1956, two civilian surveyors chanced on the wreck and noted its exact location, which otherwise remained unknown for the next 40 years. In 1997 one of the surveyors provided the coordinates to two distinct expeditions, one American and one led by the Canadian Department of National Defence
, seeking to conduct an environmental analysis of the site. Both expeditions reached the wreck around the same time, and members were apparently the first humans to set foot in the area since 1956. These environmental missions found no unusual radiation
levels, and led to the crash location becoming public knowledge. Local salvage efforts began, with many items going to local museums. In late 1998, the Canadian government declared the site protected.
rather than into the Pacific. To reach the crash location, the plane had to have flown north for some hours after the crew had bailed out, and to have cleared terrain whose altitude exceeded the altitude at which the crew bailed out. It can be surmised that the three engines that were not shut down must have recovered from icing, resulting in enough increased power to enable the aircraft to remain airborne and even climb. It is possible that the autopilot turn setting caused the abandoned plane to fly in circles, after which prevailing winds carried it to the crash site. Rescue and weather records show the strength and direction of prevailing winds to be consistent with this scenario. An alternative theory is the plane entered a warm air current, the ice on one wing melted, and the weight change caused the plane to bank then fly in circles. Then the ice on the other wing fell off. The plane continued over the mountains and into the BC Interior, where it crashed.
It has been speculated that Captain Ted Schreier, one of the five crew members whose bodies were never found, did not bail out with the others, but instead tried to fly the plane back to Alaska. A local legend in Smithers, BC, has it that the USAF recovered a body from the wreckage in 1954.
Convair B-36
The Convair B-36 "Peacemaker" was a strategic bomber built by Convair and operated solely by the United States Air Force from 1949 to 1959. The B-36 was the largest mass-produced piston engine aircraft ever made. It had the longest wingspan of any combat aircraft ever built , although there have...
, serial number 44-92075 assigned to the 7th Bomb Wing at Carswell Air Force Base
Carswell Air Force Base
Carswell Air Force Base, was a United States Air Force Strategic Air Command base located about northwest central of Fort Worth, Texas, United States; the air force base is mostly within the Fort Worth city limits and has portions within Westworth and White Settlement...
, crashed in northern British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
after jettisoning a Mark IV
Mark 4 nuclear bomb
The Mark 4 nuclear bomb was an American nuclear bomb design produced starting in 1949 and in use until 1953.The Mark 4 was based on the earlier Mark 3 Fat Man design, used in the Trinity test and the bombing of Nagasaki...
atomic bomb. This was the first such nuclear weapon loss
United States military nuclear incident terminology
The United States Armed Forces uses a number of terms to define the magnitude and extent of nuclear incidents.-Origin:United States Department of Defense directive 5230.16, Nuclear Accident and Incident Public Affairs Guidance, Chairman Joint Chiefs of Staff Manual 3150.03B Joint Reporting...
in history. The Convair had been en route from Eielson Air Force Base
Eielson Air Force Base
Eielson Air Force Base is a United States Air Force base located approximately southeast of Fairbanks, Alaska and just southeast of Moose Creek, Alaska....
near Fairbanks, Alaska
Fairbanks, Alaska
Fairbanks is a home rule city in and the borough seat of the Fairbanks North Star Borough in the U.S. state of Alaska.Fairbanks is the largest city in the Interior region of Alaska, and second largest in the state behind Anchorage...
to Carswell AFB in Fort Worth, Texas
Fort Worth, Texas
Fort Worth is the 16th-largest city in the United States of America and the fifth-largest city in the state of Texas. Located in North Central Texas, just southeast of the Texas Panhandle, the city is a cultural gateway into the American West and covers nearly in Tarrant, Parker, Denton, and...
, on a mission that included a simulated nuclear attack on San Francisco, California
San Francisco, California
San Francisco , officially the City and County of San Francisco, is the financial, cultural, and transportation center of the San Francisco Bay Area, a region of 7.15 million people which includes San Jose and Oakland...
.
Incident
Convair 44-92075 was on a mission that was part of the first full-scale practice nuclear strike against the Soviet UnionSoviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
. Each B-36 involved in this exercise was to conduct a simulated nuclear attack on an American city. The exercise was also intended to test whether the B-36 could attack the Soviet Union
Soviet Union
The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....
during the Arctic winter, when temperatures are so low that if a plane engine were shut down while a plane was being serviced on the ground, the engine could not be restarted.
Plane 44-92075 took off from Eielson AFB with a crew of 16 plus one observer. The plan for the 24-hour flight was to fly over the North Pacific, due west of the Alaska panhandle
Alaska Panhandle
Southeast Alaska, sometimes referred to as the Alaska Panhandle, is the southeastern portion of the U.S. state of Alaska, which lies west of the northern half of the Canadian province of British Columbia. The majority of Southeast Alaska's area is part of the Tongass National Forest, the United...
and British Columbia
British Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
, then head inland over Washington state and Montana
Montana
Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...
. The flight plan did not include any penetration of Canadian airspace
Airspace
Airspace means the portion of the atmosphere controlled by a country above its territory, including its territorial waters or, more generally, any specific three-dimensional portion of the atmosphere....
. The plane carried a Mark IV
Mark 4 nuclear bomb
The Mark 4 nuclear bomb was an American nuclear bomb design produced starting in 1949 and in use until 1953.The Mark 4 was based on the earlier Mark 3 Fat Man design, used in the Trinity test and the bombing of Nagasaki...
atomic bomb, containing a substantial quantity of natural uranium
Natural uranium
Natural uranium refers to refined uranium with the same isotopic ratio as found in nature. It contains 0.7 % uranium-235, 99.3 % uranium-238, and a trace of uranium-234 by weight. In terms of the amount of radioactivity, approximately 2.2 % comes from uranium-235, 48.6 % uranium-238, and 49.2 %...
and 500 pounds of conventional explosives. According to the USAF, the bomb did not contain the plutonium core necessary for a nuclear detonation.
Cold weather (-40F on the ground at Eielson AFB) adversely affected the planes involved in this exercise, and some minor difficulties with 44-92075 were noted before takeoff. Seven hours into the flight, three of the six engines began shooting flames and were shut down, and the other three engines proved incapable of delivering full power. The subsequent investigation blamed ice buildup
Carburetor icing
Carburetor, or carb icing, is an icing condition which can affect any carburetor under certain atmospheric conditions. Carburetor icing occurs when there is humid air, and the temperature drop in the venturi causes the water vapor to freeze. The ice will form on the surfaces of the carburetor...
in the mixture control
Aircraft engine controls
Aircraft engine controls provide a means for the pilot to control and monitor the operation of the aircraft's powerplant. This article describes controls used with a basic internal-combustion engine driving a propeller. Some optional or more advanced configurations are described at the end of the...
air intakes.
The crew decided to abandon the aircraft because it could not stay aloft with three engines out of commission while carrying a heavy payload. The atomic bomb was jettisoned and detonated in mid-air, resulting in a large conventional explosion over the Pacific. The USAF later stated that the fake practice core on board the aircraft was inserted into the weapon before it was dropped.
The aircraft commander steered the plane over Princess Royal Island
Princess Royal Island
Princess Royal Island is the largest island on the North Coast of British Columbia, Canada. It is located amongst the isolated inlets and islands east of Hecate Strait on the British Columbia Coast. At , it is the fourth largest island in British Columbia...
to spare his crew having to parachute into the cold North Pacific, whereupon the crew bailed out. Before bailing out last, the he set a turning course toward the open ocean using the autopilot
Autopilot
An autopilot is a mechanical, electrical, or hydraulic system used to guide a vehicle without assistance from a human being. An autopilot can refer specifically to aircraft, self-steering gear for boats, or auto guidance of space craft and missiles...
.
The plane had been in constant radio contact with the Strategic Air Command
Strategic Air Command
The Strategic Air Command was both a Major Command of the United States Air Force and a "specified command" of the United States Department of Defense. SAC was the operational establishment in charge of America's land-based strategic bomber aircraft and land-based intercontinental ballistic...
and within minutes of the bailout the Royal Canadian Air Force
Royal Canadian Air Force
The history of the Royal Canadian Air Force begins in 1920, when the air force was created as the Canadian Air Force . In 1924 the CAF was renamed the Royal Canadian Air Force and granted royal sanction by King George V. The RCAF existed as an independent service until 1968...
launched Operation Brix to find the missing men. Poor weather hampered search efforts; nevertheless 12 of the 17 men were eventually found alive. The five deceased airmen were believed to have bailed out of the aircraft earlier than the surviving crew members, and it was assumed that they landed in the ocean and drowned. Canadian authorities were never told that the aircraft was carrying a nuclear weapon.
Subsequent events
No exhaustive search was launched for the plane as it was believed to be at the bottom of the Pacific. Three years later, however, a RCAF flight searching for the missing de Havilland DoveDe Havilland Dove
The de Havilland DH.104 Dove was a British monoplane short-haul airliner from de Havilland, the successor to the biplane de Havilland Dragon Rapide and was one of Britain's most successful post-war civil designs...
aircraft of Texas millionaire oilman Ellis Hall spotted the B-36's wreckage. It was nearly completely intact, on the side of Mount Kologet, about 50 miles (80.5 km) from the Alaskan border, roughly due east of the towns of Stewart, BC
Stewart, British Columbia
Stewart is a small town, incorporated as a district municipality at the head of the Portland Canal in northwestern British Columbia, Canada. In 2006, its population was about 496.-History:...
and Hyder, AK
Hyder, Alaska
Hyder is a census-designated place in Prince of Wales-Hyder Census Area, Alaska, United States. At the 2000 census the population was 97. Hyder has achieved fame as a point in Alaska accessible to automobile and motorbike travelers in Canada who want to say that they have been to Alaska...
, on the east side of the isolated Nass
Nass River
The Nass River is a river in northern British Columbia, Canada. It flows from the Coast Mountains southwest to Nass Bay, a sidewater of Portland Inlet, which connects to the North Pacific Ocean via the Dixon Entrance...
Basin northwest of Hazelton, British Columbia
Hazelton, British Columbia
Hazelton is a small town located at the junction of the Bulkley and Skeena Rivers in northern British Columbia, Canada. It was founded in 1866 and has a population of 293...
.
The USAF immediately began an investigation. A team was sent in September 1953 but the effort was not given a high priority. After 19 days of trudging through the wilderness, they failed to reach the site. The effort was resumed the following year with better equipment, and in August 1954 a new team of USAF personnel accompanied by a local guide reached the wreckage. They recovered important components and then used explosives to destroy what was visible above the snow. The American and Canadian military kept the location of the wreck secret, though the operation had been run openly and the general details were known to the public. Curiously, when the American military first released information about the crash decades later, the documents falsely stated that the wreck had been found on distant Vancouver Island
Vancouver Island
Vancouver Island is a large island in British Columbia, Canada. It is one of several North American locations named after George Vancouver, the British Royal Navy officer who explored the Pacific Northwest coast of North America between 1791 and 1794...
.
In 1956, two civilian surveyors chanced on the wreck and noted its exact location, which otherwise remained unknown for the next 40 years. In 1997 one of the surveyors provided the coordinates to two distinct expeditions, one American and one led by the Canadian Department of National Defence
Department of National Defence (Canada)
The Department of National Defence , frequently referred to by its acronym DND, is the department within the government of Canada with responsibility for all matters concerning the defence of Canada...
, seeking to conduct an environmental analysis of the site. Both expeditions reached the wreck around the same time, and members were apparently the first humans to set foot in the area since 1956. These environmental missions found no unusual radiation
Radiation
In physics, radiation is a process in which energetic particles or energetic waves travel through a medium or space. There are two distinct types of radiation; ionizing and non-ionizing...
levels, and led to the crash location becoming public knowledge. Local salvage efforts began, with many items going to local museums. In late 1998, the Canadian government declared the site protected.
Discussion
It is not known just how 44-92075 crashed into Mount Kologet in the mountains of northern British ColumbiaBritish Columbia
British Columbia is the westernmost of Canada's provinces and is known for its natural beauty, as reflected in its Latin motto, Splendor sine occasu . Its name was chosen by Queen Victoria in 1858...
rather than into the Pacific. To reach the crash location, the plane had to have flown north for some hours after the crew had bailed out, and to have cleared terrain whose altitude exceeded the altitude at which the crew bailed out. It can be surmised that the three engines that were not shut down must have recovered from icing, resulting in enough increased power to enable the aircraft to remain airborne and even climb. It is possible that the autopilot turn setting caused the abandoned plane to fly in circles, after which prevailing winds carried it to the crash site. Rescue and weather records show the strength and direction of prevailing winds to be consistent with this scenario. An alternative theory is the plane entered a warm air current, the ice on one wing melted, and the weight change caused the plane to bank then fly in circles. Then the ice on the other wing fell off. The plane continued over the mountains and into the BC Interior, where it crashed.
It has been speculated that Captain Ted Schreier, one of the five crew members whose bodies were never found, did not bail out with the others, but instead tried to fly the plane back to Alaska. A local legend in Smithers, BC, has it that the USAF recovered a body from the wreckage in 1954.
Sources
- "Broken Arrow," BC Aviation Magazine.
- Site with links to Canadian Dept. of National Defence report and to news stories.
- Site with pictures of the crash site.
- Transcript of an interview with a crew survivor.
- "Broken Arrow - The Declassified History of U.S. Nuclear Weapons Accidents" by Michael H. Maggelet and James C. Oskins ISBN 978-1-4357-0361-2.