You do not have permission to edit this page, for the following reasons:

This IP address has been blocked from editing Wikipedia.
This does not affect your ability to read Wikipedia pages.
Most people who see this message have done nothing wrong. Some kinds of blocks restrict editing from specific service providers or telecom companies in response to recent abuse or vandalism, and can sometimes affect other users who are unrelated to that abuse. Review the information below for assistance if you do not believe that you have done anything wrong.

The IP address or range 44.214.0.0/16 has been blocked by ‪Blablubbs‬ for the following reason(s):

The IP address that you are currently using has been blocked because it is believed to be a web host provider or colocation provider. To prevent abuse, web hosts and colocation providers may be blocked from editing Wikipedia.
You will not be able to edit Wikipedia using a web host or colocation provider because it hides your IP address, much like a proxy or VPN.
We recommend that you attempt to use another connection to edit. For example, if you use a proxy or VPN to connect to the internet, turn it off when editing Wikipedia. If you edit using a mobile connection, try using a Wi-Fi connection, and vice versa. If you are using a corporate internet connection, switch to a different Wi-Fi network. If you have a Wikipedia account, please log in.
If you do not have any other way to edit Wikipedia, you will need to request an IP block exemption.

How to appeal if you are confident that your connection does not use a colocation provider's IP address:
If you are confident that you are not using a web host, you may appeal this block by adding the following text on your talk page: ((unblock|reason=Caught by a colocation web host block but this host or IP is not a web host. My IP address is _______. Place any further information here. ~~~~)). You must fill in the blank with your IP address for this block to be investigated. Your IP address can be determined here. Alternatively, if you wish to keep your IP address private you can use the unblock ticket request system. There are several reasons you might be editing using the IP address of a web host or colocation provider (such as if you are using VPN software or a business network); please use this method of appeal only if you think your IP address is in fact not a web host or colocation provider.

Administrators: The IP block exemption user right should only be applied to allow users to edit using web host in exceptional circumstances, and requests should usually be directed to the functionaries team via email. If you intend to give the IPBE user right, a CheckUser needs to take a look at the account. This can be requested most easily at SPI Quick Checkuser Requests. Unblocking an IP or IP range with this template is highly discouraged without at least contacting the blocking administrator.

This block will expire on 16:45, 10 January 2025. Your current IP address is 44.214.4.121.

Even when blocked, you will usually still be able to edit your user talk page, as well as email administrators and other editors.

For information on how to proceed, please read the FAQ for blocked users and the guideline on block appeals. The guide to appealing blocks may also be helpful.

Other useful links: Blocking policy · Help:I have been blocked
This IP address range has been globally blocked.
This does not affect your ability to read Wikipedia pages.
Most people who see this message have done nothing wrong. Some kinds of blocks restrict editing from specific service providers or telecom companies in response to recent abuse or vandalism, and can sometimes affect other users who are unrelated to that abuse. Review the information below for assistance if you do not believe that you have done anything wrong.

This block affects editing on all Wikimedia wikis.
The IP address or range 44.214.0.0/16 has been globally blocked by ‪AntiCompositeNumber‬ for the following reason(s):

Open proxy/Webhost: Visit the FAQ if you are affected

This block will expire on 13:57, 18 February 2025. Your current IP address is 44.214.4.121.

Even while globally blocked, you will usually still be able to edit pages on Meta-Wiki.

If you believe you were blocked by mistake, you can find additional information and instructions in the No open proxies global policy. Otherwise, to discuss the block please post a request for review on Meta-Wiki. You could also send an email to the stewards VRT queue at stewards@wikimedia.org including all above details.

Other useful links: Global blocks · Help:I have been blocked

You can view and copy the source of this page:

((short description|1968 aviation accident))
((pp-move-indef))
((Use dmy dates|date=October 2019))
((Infobox aircraft occurrence
| name = 1968 Thule Air Base B-52 crash
| image = Boeing B-52G in flight 061026-F-1234S-021.jpg
| image_upright = 1.15
| alt =
| caption = A B-52G, similar to the one that crashed at Thule Air Base
| date = 21 January 1968
| type = [[In-flight fire]] leading to crew [[Ejection seat|ejecting]] 
| occurrence_type = Accident
| site = ((convert|7.5|mi|km)) west of [[Thule Air Base]] (formerly [[Pituffik]]), [[Greenland]]
| coords = ((coord|76|31|40|N|69|16|55|W|display=inline,title|scale:50000_region:GL_type:event))((sfn|Project Crested Ice 1969: The Thule Accident|p=9))
| aircraft_type = [[Boeing B-52 Stratofortress|B-52G Stratofortress]]
| aircraft_name =
| operator = [[380th Air Expeditionary Wing|380th Strategic Bomb Wing]], [[Strategic Air Command]], [[United States Air Force]]
| tail_number = 58-0188
| origin = [[Plattsburgh Air Force Base]]
| stopover = [[Baffin Bay]] ([[holding pattern]])
| stopover0 =
| stopover1 =
| stopover2 =
| stopover3 =
| last_stopover =
| destination = Plattsburgh Air Force Base((sfn|Project Crested Ice 1969: The Thule Accident|p=1))
| crew = 7
| fatalities = 1
| injuries = 0
| survivors = 6 (all excluding one crew member)
))

On 21 January 1968, an aircraft accident, sometimes known as the '''Thule affair''' or '''Thule accident''' (((IPAc-en|ˈ|t|uː|l|i)); ((lang-da|Thuleulykken))), involving a [[United States Air Force]] (USAF) [[Boeing B-52 Stratofortress|B-52 bomber]] occurred near [[Thule Air Base]] in the Danish territory of [[Greenland]]. The aircraft was carrying four [[B28 nuclear bomb|B28FI thermonuclear bombs]] on a [[Cold War]] "[[Operation Chrome Dome|Chrome Dome]]" alert mission over [[Baffin Bay]] when a cabin fire forced the crew to abandon the aircraft before they could carry out an [[emergency landing]] at [[Thule Air Base]]. Six crew members ejected safely, but one who did not have an [[ejection seat]] was killed while trying to bail out. The bomber crashed onto [[sea ice]] in [[North Star Bay]],((efn|Also known as Bylot Sound.)) Greenland, causing the conventional explosives aboard to detonate and the nuclear payload to rupture and disperse, resulting in [[radioactive contamination]] of the area.

The United States and Denmark launched an intensive clean-up and recovery operation, but the [[Teller–Ulam design#Basic principle|secondary stage]] of one of the nuclear weapons could not be accounted for after the operation was completed. USAF [[Strategic Air Command]] "Chrome Dome" operations were discontinued immediately after the accident, which highlighted the safety and political risks of the missions. Safety procedures were reviewed, and more stable explosives were developed for use in nuclear weapons.

In 1995, a political scandal arose in Denmark after a report revealed the government had given tacit permission for nuclear weapons to be located in Greenland, in contravention of Denmark's 1957 [[nuclear-free zone]] policy. Workers involved in the clean-up program campaigned for compensation for radiation-related illnesses they experienced in the years after the accident.

__TOC__((clear))<!-- Stops infobox intruding into next section -->

== Thule Monitor Mission ==
[[File:Thule BMEWS.jpg|thumb|[[Ballistic Missile Early Warning System|BMEWS]] antennas at Thule, with a modern Satellite Control Network [[radome]] on the right|alt=A series of four metal structures silhouetted on the horizon, with a golf ball looking dome to the left]]

In 1960, the [[USAF]] [[Strategic Air Command]] (SAC) began [[Operation Chrome Dome]], a [[Cold War]] airborne alert program devised by General [[Thomas S. Power]] to fly nuclear-armed [[Boeing B-52 Stratofortress]] bombers to the borders of the Soviet Union. The flights were scheduled to ensure that twelve bombers were aloft at all times.((sfn|Time 1961&nbsp;– Deadly Daily Dozen))((sfn|Croddy|Wirtz|2005|p=3)) These bombers gave SAC offensive capability in the event of a Soviet [[Pre-emptive nuclear strike|first strike]],((sfn|Clarke|2006|pp=70–73))((sfn|Croddy|Wirtz|2005|p=3)) Beginning in 1961, B-52 bombers also secretly flew as part of the "Hard Head" mission (or "Thule Monitor Missions") over Thule Air Base. The objective of "Hard Head" was to maintain constant visual surveillance of the base's strategically important [[Ballistic Missile Early Warning System]] (BMEWS), which provided early warning of Soviet missile launches.((sfn|Project Crested Ice 1969: The Thule Accident|p=5)) This ensured that, if the communication link between [[North American Aerospace Defense Command]] and the base was severed, then the aircraft crew could determine if the interruption resulted from an actual attack or a mere technical failure.((sfn|Croddy|Wirtz|2005|p=3))((sfn|Sagan|1995|pp=170–176))((efn|Satellite verification and monitoring were not possible at the time.)) The monitoring mission started when the designated aircraft reached a [[waypoint]] at ((coord|75|0|N|67|30|W|type:landmark|display=inline)) in Baffin Bay and entered a figure-eight [[Holding (aeronautics)|holding pattern]] above the air base at an altitude of ((convert|35000|ft|m)).((sfn|Project Crested Ice 1969: The Thule Accident|p=5))

((Location map+|Greenland|width=180|float=right|caption=Greenland|relief=1|alt=Map of Greenland showing the location of Thule on its northwestern shore|places=
((Location map~|Greenland|lon_dir=W|lat_dir=N|lat_deg=76|lat_min=31|lon_deg=69|lon_min=13|label=Thule&nbsp;Air&nbsp;Base|position=right))
((Location map~|Greenland|lon_dir=W|lat_dir=N|lat_deg=73|lat_min=24|lon_deg=68|lon_min=8|label=Baffin Bay|position=right))
))

In 1966, United States Secretary of Defense [[Robert McNamara]] proposed cutting "Chrome Dome" flights because the BMEWS system was fully operational, the bombers had been made redundant by missiles, and $123&nbsp;million ($((Formatprice|((Inflation|US|123000000|1966|r=-4))|0)) as of ((CURRENTISOYEAR))) could be saved annually. SAC and the [[Joint Chiefs of Staff]] opposed the plan, so a compromise was reached whereby a smaller force of four bombers would be on alert each day. Despite the reduced program and the risks highlighted by the [[1966 Palomares B-52 crash]], SAC continued to dedicate one of the aircraft to monitoring Thule Air Base. This assignment was without the knowledge of civilian authorities in the United States, who SAC determined did not have the "[[need to know]]" about specific operational points.((sfn|Sagan|1995|pp=178–180))

== Broken Arrow ==
On 21 January 1968, a B-52G Stratofortress, serial number 58-0188, with the [[call sign|callsign]] "HOBO 28"((sfn|Project Crested Ice 1970: Danish Atomic Energy Commission|p=2)) from the [[380th Air Expeditionary Wing|380th Strategic Bomb Wing]] at [[Plattsburgh Air Force Base]], New York was assigned the "Hard Head" mission over Thule and nearby [[Baffin Bay]].((sfn|B-52 Crash at Thule Air Base 1968&nbsp;– USAEC|p=38))  The bomber crew consisted of five regular crew members, including Captain John Haug, the aircraft commander; Radar navigator Major Frank Hopkins; and Electronic warfare officer Captain Richard Marx. Also aboard were a substitute navigator (Captain Curtis R. Criss((sfn|Dresser|1970|pp=25–26))) and a mandatory third pilot (Major Alfred D'Amario).<ref>((cite report | title = USAF Accident/Incident Report | date = 21 January 1968 | publisher = United States Air Force ))</ref>

Before take-off, D'Amario placed three cloth-covered foam cushions on top of a heating vent under the instructor navigator's seat in the aft section of the lower deck. Shortly after take-off, another cushion was placed under the seat. The flight was uneventful until the scheduled mid-air refueling from a [[KC-135 Stratotanker]], which had to be conducted manually because of an error with the B-52G's autopilot. About one hour after refueling, while the aircraft was circling above its designated area, Captain Haug directed co-pilot Svitenko to take his rest period. His seat was taken by the spare pilot, D'Amario. The crew was uncomfortable because of the cold, although the heater's [[Potentiometer#Rheostat|rheostat]] was turned up, so D'Amario opened an [[Bleed air|engine bleed valve]] to draw additional hot air into the heater from the engine manifold.((sfn|Project Crested Ice 1969: The Thule Accident|p=5)) Because of a heater malfunction, the air barely cooled as it traveled from the engine manifold to the cabin's heating ducts. During the next half-hour, the cabin's temperature became uncomfortably hot,((sfn|Eriksson|2002|p=11)) and the stowed cushions ignited.((sfn|Project Crested Ice 1969: The Thule Accident|p=3)) After one crew member reported smelling burning rubber, they looked for a fire. The navigator searched the lower compartment twice before discovering the fire behind a metal box.((sfn|Project Crested Ice 1970: Danish Atomic Energy Commission|p=2)) He attempted to fight it with two fire extinguishers, but could not put it out.((sfn|Project Crested Ice 1970: Danish Atomic Energy Commission|p=2))((sfn|Project Crested Ice 1969: The Thule Accident|p=7))

[[File:Thule air base above.jpeg|thumb|Thule Air Base in the foreground with North Star Bay, which was covered in sea ice at the time of the accident, in the background|alt=Aerial photograph, land masses are covered in snow, but the bay is not frozen over]]

At 15:22&nbsp;EST, about six hours into the flight and ((convert|90|mi|km)) south of Thule Air Base, Haug declared an emergency. He told Thule [[air traffic control]] that he had a fire on board and requested permission to perform an emergency landing at the air base.((sfn|B-52 Crash at Thule Air Base 1968&nbsp;– USAEC|p=7)) Within five minutes, the aircraft's fire extinguishers were depleted, electrical power was lost and smoke filled the cockpit to the point that the pilots could not read their instruments.((sfn|B-52 Crash at Thule Air Base 1968&nbsp;– USAEC|p=38))<ref name="InterimReport">AEC Observers' Interim Report of Thule Accident, 1968</ref> As the situation worsened, the captain realized he would not be able to land the aircraft and told the crew to prepare to abandon it. They awaited word from D'Amario that they were over land, and when he confirmed that the aircraft was directly over the lights of Thule Air Base, the four crewmen ejected, followed shortly thereafter by Haug and D'Amario. The co-pilot, Leonard Svitenko, who had given up his ejection seat when the spare pilot took over from him, sustained fatal head injuries when he attempted to bail out through one of the lower hatches.((sfn|Project Crested Ice 1969: The Thule Accident|p=7))((sfn|Project Crested Ice 1970: Danish Atomic Energy Commission|p=4))((sfn|The Flight of HOBO 28|pp=2–3))

The pilotless aircraft initially continued north, then turned left through 180° and crashed onto sea ice in North Star Bay at a relatively shallow angle of 20&nbsp;degrees—about ((convert|7.5|mi|km)) west of Thule Air Base—at 15:39&nbsp;EST.((efn|Some sources say [[Wolstenholme Fjord]] is a more accurate description of the area.((sfn|Project Crested Ice 1969: The Thule Accident|p=7)))) The conventional [[explosive material#High explosives|high explosive]] (HE) components of four 1.1&nbsp;[[TNT equivalent|megaton]]((sfn|Taagholt|Hansen|2001|p=42)) [[B28 nuclear bomb|B28FI thermonuclear bombs]] detonated on impact, spreading [[radioactive contamination|radioactive material]] over a large area in a manner similar to a [[dirty bomb]].((sfn|Vantine|Crites|2003)) ((cnspan|[[Strong link weak link|"Weak links"]] in the weapon design ensured that a [[Nuclear fission|nuclear explosion]] was not triggered. The extreme heat generated by the burning of ((convert|225000|lb|t)) of jet fuel during the five to six hours after the crash melted the ice sheet, causing wreckage and munitions to sink to the [[ocean floor]].|date=March 2023))

[[File:Thule Eskimos.jpg|thumb|[[Inuit]] around the base worked with the U.S. Air Force to get to the B-52 crash. The sleds were the only way to get to the crash site.|alt=]]

Haug and D'Amario parachuted onto the grounds of the air base and made contact with the base commander within ten&nbsp;minutes of each other. They informed him that at least six crew ejected successfully and the aircraft was carrying four nuclear weapons.((sfn|Dresser|1970|pp=25–26)) Off-duty staff were mustered to conduct search and rescue operations for the remaining crew members. Owing to the extreme weather conditions, Arctic darkness, and unnavigable ice, the base relied largely on the Thule representative of the Royal Greenland Trade Department, Ministry of Greenland, Jens Zinglersen, to raise and mount the search using native dog sled teams.((sfn|Hunziker|p=13)) Three of the survivors landed within ((convert|1.5|mi|km)) of the base and were rescued within two&nbsp;hours.((sfn|Project Crested Ice 1970: Danish Atomic Energy Commission|pp=3–4))((sfn|Project Crested Ice 1969: The Thule Accident|p=8)) For his initial actions and later services, Zinglersen received the Air Force Exceptional Civilian Service Medal on 26 February 1968 at the hands of the U.S. Ambassador, K. E. White.((sfn|Dresser|1970|pp=25–26)) Gunner Staff Sergeant Calvin Snapp, who was first to eject, landed ((convert|6|mi|km)) from the base—he remained lost on an ice floe for 21&nbsp;hours and suffered [[hypothermia]] in the ((convert|-23|F|C)) temperatures,((sfn|Dresser|1970|pp=25–26)) but he survived by wrapping himself in his parachute.((sfn|Dresser|1970|pp=25–26))((sfn|Project Crested Ice 1969: The Thule Accident|p=8))

An aerial survey of the crash site immediately afterwards showed only six engines, a tire and small items of debris on the blackened surface of the ice.((sfn|B-52 Crash at Thule Air Base 1968&nbsp;– USAEC|p=2)) The accident was designated a [[United States military nuclear incident terminology#Broken Arrow|Broken Arrow]], or an accident involving a nuclear weapon but which does not present a risk of war.((sfn|Natonski|2007|p=1))((sfn|Project Crested Ice 1970: Danish Atomic Energy Commission|p=12))

== Project Crested Ice ==
[[File:Thule AFB B-52 Crash Site.jpg|thumb|upright|Aerial photograph of blackened ice at the crash scene, with the point of impact at the top|alt=Aerial photograph of the crash site showing a long black mark that looks like an ink blot on white paper]]

The resulting explosion and fire destroyed many of the components that had scattered widely in a ((convert|1|mi|km|adj=on)) by ((convert|3|mi|km|adj=on)) area.((sfn|McElwee|1968|p=38)) Parts of the [[bomb bay]] were found ((convert|2|mi|km)) north of the impact area, indicating the aircraft started to break-up before impact.((sfn|Project Crested Ice 1969: The Thule Accident|p=4))((sfn|Christensen|2009|p=41)) The ice was disrupted at the point of impact, temporarily exposing an area of seawater approximately ((convert|50|m|ft|order=flip)) in diameter; ice floes in the area were scattered, upturned and displaced.((sfn|Fristrup|1970|p=86)) South of the impact area, a ((convert|400|ft|m|adj = on)) by ((convert|2200|ft|m|adj = on)) blackened patch was visible where fuel from the aircraft had burned—this area was highly contaminated with [[JP-4 (fuel)|JP-4]] aviation fuel and radioactive elements((sfn|Fristrup|1970|p=86)) that included [[plutonium]], [[uranium]], [[americium]] and [[tritium]].((sfn|Eriksson|2002|p=28))((sfn|Dose Evaluation Report 2001|p=2))((sfn|National Board of Health 2011|p=16)) Plutonium levels as high as 380&nbsp;mg/m<sup>2</sup> were registered in the area.((sfn|Vantine|Crites|2003))

{| class="wikitable"
|+Radioactive materials at the accident site((sfn|National Board of Health 2011|p=16))
![[Nuclide]]
![[Half-life]]
!Type of radiation
|-
|[[Uranium-238]]
|4.5&nbsp;billion years
|[[Alpha decay|Alpha]]
|-
|[[Uranium-235]]
|700&nbsp;million years
|Alpha
|-
|[[Uranium-234]]
|250,000 years
|Alpha
|-
|[[Plutonium-239]]
|24,000 years
|Alpha
|-
|[[Americium-241]]
|430 years
|Alpha/[[Gamma ray|Gamma]]
|-
|[[Plutonium-240]]
|6,600 years
|Alpha
|-
|[[Plutonium-241]]
|14 years
|[[Beta decay|Beta]]
|-
|[[Tritium]]
|12 years
|Beta
|}


American and Danish officials immediately launched "Project Crested Ice" (informally known as "Dr. Freezelove"((efn|"Dr. Freezelove" is an apparent [[pun|play on words]] of the 1964 film "[[Dr. Strangelove]]".))((sfn|Hanhimäki|Westad|2004|pp=300–301))), a clean-up operation to remove the debris and contain environmental damage.((sfn|Schwartz|1998|p=410)) Despite the cold, dark Arctic winter, there was considerable pressure to complete the clean-up operation before the sea ice melted in the spring and deposited further contaminants into the sea.((sfn|Project Crested Ice 1969: The Thule Accident|p=50))

[[File:Camp Hunziker.jpg|thumb|Camp Hunziker was set up at the accident site]]

Weather conditions at the site were extreme; the average temperature was ((convert|-40|C|F|0|order=flip)), at times dropping to ((convert|-60|C|F|0|order=flip)). These temperatures were accompanied by winds of up to ((convert|40|m/s|mph|sp=us|order=flip)). Equipment suffered high failure-rates and batteries worked for shorter periods in the cold; operators modified their scientific instruments to allow the battery packs to be carried under their coats to extend the batteries' lifespan.((sfn|McElwee|1968|p=6)) The operation was conducted in [[polar night|arctic darkness]] until 14 February, when sunlight gradually began appearing.((sfn|Schwartz|1998|p=410))((sfn|Project Crested Ice 1970: Danish Atomic Energy Commission|p=13))

A base camp (named "Camp Hunziker"((sfn|McElwee|1968|p=13,47)) after [[Richard Overton Hunziker]], the USAF general in charge of the operation), was created at the crash site; it included a heliport, igloos, generators and communications facilities. A "zero line" delineating the ((convert|1|mi|km|adj=on)) by ((convert|3|mi|km|adj=on)) area in which [[alpha particle]] contamination could be measured was established by 25 January, four days after the crash.((sfn|Broken Arrow 1968&nbsp;– Thule|p=5)) The line was subsequently used to control [[Human decontamination|decontamination]] of personnel and vehicles. An [[ice road]] was constructed to Thule from the site. This was followed by a second, more-direct road so that the ice on the first road was not fatigued by overuse.((sfn|Dresser|1970|p=26)) The camp later included a large prefabricated building, two ski-mounted buildings, several huts, a decontamination trailer and a latrine.((sfn|Broken Arrow 1968&nbsp;– Thule|p=3)) These facilities allowed for 24-hour operations at the crash site.((sfn|Broken Arrow 1968&nbsp;– Thule|p=3))

[[File:Crested Ice Tank Loading.jpg|thumb|Contaminated ice being loaded into steel tanks at Thule during Project Crested Ice|alt=A crane shown loading contaminated ice into a large steel tank.]]

The USAF worked with Danish nuclear scientists to consider the clean-up options. The spilled fuel in the blackened area was heavily contaminated, raising concerns that when the ice melted in the summer, the radioactive fuel would float on the sea and subsequently contaminate the shore. The Danes thus insisted on the removal of the blackened area to avoid this possibility.((sfn|Joint Committee on Atomic Energy 1968|pp=23, 26))  The Danes also requested that the nuclear material not be left in Greenland after the cleanup operation was complete, therefore requiring General Hunziker to remove the contaminated ice and wreckage to the United States for disposal.((sfn|Joint Committee on Atomic Energy 1968|p=20))((sfn|Fristrup|1970|p=90)) USAF personnel used [[grader]]s to collect the contaminated snow and ice, which was loaded into wooden boxes at the crash site. The boxes were moved to a holding area near Thule Air Base known as the "Tank Farm".((sfn|Eriksson|2002|p=14)) There, contaminated material was loaded into steel tanks prior to being loaded onto ships.((sfn|Dresser|1970|p=28)) Debris from the weapons was sent to the [[Pantex]] plant in [[Texas]] for evaluation,<ref name="InterimReport" /> and the tanks were shipped to [[Savannah River Site|Savannah River]] in [[South Carolina]].((sfn|Project Crested Ice 1969: The Thule Accident|p=60))  According to General Hunziker, 93 percent of the contaminated material was removed from the accident site.((sfn|Joint Committee on Atomic Energy 1968|pp=19, 29))

In 1987–88 and again in 2000, reports surfaced in the Danish press that one of the bombs had not been recovered.((sfn|Leyne|2000)) SAC stated at the time of the accident that all four bombs were destroyed. In 2008, the [[BBC]] published an article that was based on its examination of partly declassified documents obtained some years earlier, via the United States [[Freedom of Information Act (United States)|Freedom of Information Act]]. The documents appeared to confirm that within weeks of the accident, investigators realized only three of the weapons could be accounted for.((sfn|Corera 2008-11-10&nbsp;– Mystery of lost bomb)) One of the declassified documents—dated to January 1968—details a blackened section of ice which had refrozen with [[shroud lines]] from a weapon parachute: "Speculate something melted through the ice such as burning [[Python primary|primary]] or secondary."((sfn|Corera 2008-11-10&nbsp;– Mystery of lost bomb))((efn|The "primary" and "secondary" refer to [[Teller-Ulam design|parts of the weapon]].)) A July 1968 report states, "An analysis by the AEC of the recovered secondary components indicates recovery of 85 percent of the uranium and 94 percent, by weight, of three secondaries. No parts of the fourth secondary have been identified."<ref>USAF Nuclear Safety, p. 4</ref>

The BBC tracked down several officials involved in the accident's aftermath. One was William H. Chambers, a former nuclear-weapons designer at the [[Los Alamos National Laboratory]]. Chambers headed a team dealing with nuclear accidents, including the Thule crash. He explained the logic behind the decision to abandon the search: "There was disappointment in what you might call a failure to return all of the components&nbsp;... it would be very difficult for anyone else to recover classified pieces if we couldn't find them."((sfn|Corera 2008-11-10&nbsp;– Mystery of lost bomb))

[[File:Mark 28 Thermonuclear Bomb.jpg|thumb|Set of four B28FI thermonuclear bombs of the same type as those in the accident at Thule|alt=Four silver B28FI nuclear bombs in a rack ready for loading into an aircraft.]]

In August 1968, the United States military sent a Star&nbsp;III mini-submarine to the base to look for weapon debris, especially the uranium-235 fissile core of a secondary.((sfn|Christensen|2009|p=96)) A much bigger operation at [[1966 Palomares B-52 crash|Palomares]] off the coast of Spain two years earlier led to the recovery of a lost nuclear weapon from the [[Mediterranean Sea]]; the [[B28 nuclear bomb|B28FI]] bomb was lost for 80&nbsp;days after a mid-air collision between a B-52 on a "Chrome Dome" mission and its [[KC-135 Stratotanker]] refueling aircraft.<ref>USAF Nuclear Safety, 1966</ref> Christensen asserts that the purpose of the underwater search at Thule was obvious to the Danish authorities, contrary to other reports that suggested its true purpose had been hidden from them.((sfn|Christensen|2009|p=71)) At lower levels, however, the dives were surrounded by some confidentiality. One document from July 1968 reads, "Fact that this operation includes search for object or missing weapon part is to be treated as [[Classified information in the United States|Confidential NOFORN]]",((sfn|Corera 2008-11-10&nbsp;– Mystery of lost bomb)) meaning it was not to be disclosed to non-US nationals. It continues, "For discussion with Danes, this operation should be referred to as a survey, repeat survey of bottom under impact point."((sfn|Corera 2008-11-10&nbsp;– Mystery of lost bomb)) Further indications of the search are apparent in a September 1968 interim report by the [[United States Atomic Energy Commission]], which stated, "It was further speculated that the missing ''<redacted>'', in view of its ballistic characteristics, may have come to rest beyond the observed concentration of heavy debris."((sfn|Thule Status Report 1968|p=3)) This discussion was a reference to the unsuccessful search for the uranium cylinder of one of the secondaries.((sfn|Christensen|2009|pp=94–95))

The underwater search was beset by technical problems and eventually abandoned. Diagrams and notes included in the declassified documents make clear it was not possible to search the entire area where crash debris had spread. Four bomb reservoirs, one nearly intact [[Teller-Ulam design|secondary]], and parts equaling two secondaries were recovered on the sea ice; parts equaling one secondary were not accounted for.<ref>USAF Nuclear Safety, 1968</ref> The search also revealed a weapon [[cable fairing]], polar cap, and a one-foot by three-foot section of a warhead's ballistic case.((sfn|Thule Status Report 1968|p=2))

The United States Air Force monitored airborne contamination through nasal swabs of onsite personnel. Of the 9,837 nasal swabs taken, 335 samples had detectable levels of alpha particle activity, although none were above acceptable levels. [[Urinalysis]] was also performed but none of the 756 samples displayed any detectable level of plutonium.((sfn|Dose Evaluation Report 2001|p=ES-1))

[[File:Submersible named Star III in front of Scripps Institution of Oceanography.JPG|thumb|Star III submersible used in the underwater search for missing bomb components|alt=Star III submersible on display outside Scripps Institution of Oceanography. The white vessel has the appearance of short, fat cigar.]]

By the time the operation concluded, 700 specialized personnel from both countries and more than 70 United States government agencies had worked for nine months to clean-up the site,((sfn|Hanhimäki|Westad|2004|pp=300–301)) often without adequate protective clothing or decontamination measures. In total, more than ((convert|550000|USgal|m3)) of contaminated liquid—along with thirty tanks of miscellaneous material, some of it contaminated—were collected at the Tank Farm.((sfn|Thule Status Report 1968|pp=3–4)) Project Crested Ice ended on 13 September 1968 when the last tank was loaded onto a ship bound for the United States.((sfn|Eriksson|2002|p=14)) The operation is estimated to have cost $9.4&nbsp;million ($((Formatprice|((Inflation|US|9400000|1968|r=-4))|0)) as of ((CURRENTISOYEAR))).((sfn|Schwartz|1998|p=410))

== Aftermath ==

=== Operation Chrome Dome ===
The accident caused controversy at the time and in the years since. It highlighted the risks Thule Air Base posed to Greenlanders from nuclear accidents and potential superpower conflicts.((sfn|Heurlin|Rynning|2005|pp=184–188)) The accident, which occurred two years after the Palomares crash, signaled the immediate end of the airborne alert program, which had become untenable because of the political and operational risks involved.((sfn|Lake|Styling|2004|p=19)) [[Scott Sagan]], a political science academic and [[anti-nuclear]] writer, postulated that if the HOBO 28 monitoring aircraft had crashed into the [[Ballistic Missile Early Warning System|BMEWS]] early warning array instead of Baffin Bay, it would have presented NORAD with a scenario (radio link to "Hard Head" aircraft and BMEWS both dead, no nuclear detonation detected) that also matched that of a surprise conventional missile attack on Thule, leaving the unreliable submarine telecommunications cable between Thule and the US mainland as the only source of information to the contrary.((sfn|Edwards|Wajcman|2005|p=163))((sfn|Sagan|1995|pp=181–182)) A satellite communications link was set up in 1974.<ref>((cite journal | last = Allen | first = D. R. |date=October 2006 | title = Thule Tracking Station: 40th Anniversary October 1961–2001 | publisher = United States Air Force | bibcode = 1978coss.conf..608A | pages = 608 | journal = In: Communications Satellite Systems Conference ))</ref>

According to [[Greenpeace]], the United States and USSR were concerned enough by accidents such as the [[1961 Goldsboro B-52 crash]], the [[1966 Palomares B-52 crash]] and the Thule accident that they agreed to take measures to ensure that a future nuclear accident would not lead the other party to conclude incorrectly that a first-strike was under way.((sfn|May|1989|p=205)) Consequently, on 30 September 1971, the two superpowers signed the "Agreement on Measures to Reduce the Risk of Nuclear War". Each party agreed to notify the other immediately in the event of an accidental, unauthorized or unexplained incident involving a nuclear weapon that could increase the risk of nuclear war.((sfn|Goldblat|2002|pp=301–302)) They agreed to use the [[Moscow–Washington hotline]], which was upgraded at the same time, for any communications.((sfn|Blacker|Duffy|1984))((sfn|Mayall|Navari|1980|pp=135–137))

By April 1964, on-alert bomber missions were in decline as American strategy favored unmanned delivery via [[Intercontinental ballistic missile|ICBMs]].((sfn|Pomeroy|2006|p=123))

=== Weapon safety ===
Following the Palomares and Thule accidents—the only cases where the conventional explosives of U.S. nuclear bombs accidentally detonated and dispersed nuclear materials((rs|date=March 2023))((sfn|Global Security 2005&nbsp;– Broken Arrows))—investigators concluded the high explosive (HE) used in nuclear weapons was not [[Chemical stability|chemically stable]] enough to withstand the forces involved in an aircraft accident. They also determined that the electrical circuits of the weapons' safety devices became unreliable in a fire and allowed connections to [[short circuit]]. The findings triggered research by scientists in the United States into safer conventional explosives and fireproof casings for nuclear weapons.((sfn|Zukas|Walters|2002|pp=305–307))

The [[Lawrence Livermore National Laboratory]] developed the "[[Explosives safety#Susan Test|Susan Test]]", which uses a special projectile whose design simulates an aircraft accident by squeezing and nipping explosive material between its metal surfaces.((sfn|Zukas|Walters|2002|pp=305–307)) The test projectile is fired under controlled conditions at a hard surface to measure the reactions and thresholds of different explosives to an impact. By 1979, the [[Los Alamos National Laboratory]] developed a new, safer type of explosive, called [[Insensitive munitions#Insensitive high explosives|insensitive high explosive]] (IHE), for use in U.S. nuclear weapons;((sfn|Plummer|Greenwood|1998|p=1))((sfn|Busch|2004|pp=50–51)) the physicist and nuclear weapons designer [[Ray Kidder]] speculated that the weapons in the Palomares and Thule accidents would probably not have detonated had IHE been available at the time.((sfn|Kidder|1991|p=32))

((anchor|Thulegate))

=== "Thulegate" political scandal ===
Denmark's nuclear-free zone policy originated in 1957, when the coalition government decided in the lead-up to the [[1957 Paris summit|Paris NATO summit]] not to stockpile nuclear weapons on its soil in peacetime.((sfn|Ørvik|1986|p=205))((sfn|Agger|Wolsgård)) The presence of the bomber in Greenland airspace in 1968 therefore triggered public suspicions and accusations that the policy was being violated.((sfn|Kristensen|2004))((sfn|Jones|1986|p=176))((sfn|Kristensen|1999)) The nature of the "Hard Head" missions was suppressed at the time of the accident;<ref>US State Department (via Nautilus.org), 1968</ref> the Danish and American governments instead claimed the bomber was not on a routine mission over Greenland and that it diverted there because of a one-off emergency.((sfn|Kristensen|1999))((sfn|Taagholt|Hansen|2001|pp=42–43)) United States documents declassified in the 1990s contradicted the Danish government's position,((sfn|Project Crested Ice 1969: The Thule Accident|pp=5–6))((sfn|B-52 Crash 1968&nbsp;– NMCC|p=3)) and therefore resulted in a 1995 political scandal that the press dubbed "Thulegate".((sfn|Kristensen|1999))

The Danish parliament commissioned a report from the Danish Institute of International Affairs (DUPI)((efn|''Dansk Udenrigspolitisk Institut.'')) to determine the history of United States nuclear overflights of Greenland and the role of Thule Air Base in this regard. When the two-volume work was published on 17 January 1997((sfn|DUPI 1997)) it confirmed that the nuclear-armed flights over Greenland were recurrent, but that the United States had acted in good faith. The report blamed Danish Prime Minister [[H. C. Hansen]] for intentionally introducing ambiguity in the Danish–U.S. security agreement: he was not asked about, nor did he mention, the official Danish nuclear policy when meeting with the United States ambassador in 1957 to discuss Thule Air Base. Hansen followed up the discussion with an infamous letter pointing out that the issue of "supplies of munition of a special kind" was not raised during the discussion, but that he had nothing further to add.((sfn|Hansen|1957)) In doing so, the report concluded, he tacitly gave the United States the go-ahead to store nuclear weapons at Thule.((sfn|Brooke|2000))

The report also confirmed that the United States stockpiled nuclear weapons in Greenland until 1965, contradicting assurances by Danish foreign minister [[Niels Helveg Petersen]] that the weapons were in Greenland's airspace, but never on the ground.((sfn|Kristensen|1999))((sfn|Brooke|2000)) The DUPI report also revealed details of [[Project Iceworm]], a hitherto secret [[United States Army]] plan to store up to 600 nuclear missiles under the [[Greenland ice sheet|Greenland ice cap]].((sfn|Taagholt|Hansen|2001|p=40))

=== Workers' compensation claims ===
[[File:ThuleRadiationCheck.jpg|thumb|upright|A monitor checks a pump operator for radioactive contamination|alt=Steel tanks with "Crested Ice" painted on them are visible in the background]]

Danish workers involved in the clean-up operation claimed long-term health problems resulted from their exposure to the radiation. Although they did not work at Camp Hunziker, the Danes worked at the Tank Farm where the contaminated ice was collected, in the port from which the contaminated debris was shipped, and also serviced the vehicles used in the clean-up. It is also possible that they were exposed to radiation in the local atmosphere.((sfn|Juel|Engholm|Storm|2005|p=5)) Many of the workers surveyed in the years following Project Crested Ice reported health problems. A 1995 survey found 410 deaths by cancers out of a sample of 1,500 workers.((sfn|Juel|Engholm|Storm|2005|p=15))

In 1986, Danish Prime Minister [[Poul Schlüter]] commissioned a radiological examination of the surviving workers. The Danish Institute for Clinical [[Epidemiology]] concluded 11 months later that cancer incidents were 40&nbsp;percent higher in Project Crested Ice workers than in workers who had visited the base before and after the operation. The Institute of Cancer Epidemiology found a 50&nbsp;percent higher cancer rate in the workers than in the general population, but could not conclude that radiation exposure was to blame.((sfn|Schwartz|1998|p=411))

In 1987, almost 200 former cleanup workers took legal action against the United States. The action was unsuccessful, but resulted in the release of hundreds of classified documents. The documents revealed that USAF personnel involved in the clean-up were not subsequently monitored for health problems, despite the likelihood of greater exposure to radiation than the Danes.((sfn|Schwartz|1998|p=411)) The United States has since instigated regular examinations of its workers.((sfn|Mulvey|2007)) In 1995, the Danish government paid 1,700 workers compensation of 50,000&nbsp;[[Danish krone|kroner]] each.((sfn|Juel|Engholm|Storm|2005|p=11))

Danish workers' health has not been regularly monitored, despite a [[European Court of Justice|European Court]] directive to the Danish government to begin examinations in the year 2000,((sfn|Corera 2008-11-10&nbsp;– Legacy of lost bomb)) and a May 2007 [[European Parliament]] resolution instructing the same.((sfn|Mulvey|2007))<ref>European Parliament, 2007</ref> In 2008, the Association of Former Thule Workers took the case to the European courts. The petitioners claimed that Denmark's failure to comply with the rulings led to delays in detecting their illnesses, resulting in worsened prognoses. The country joined the [[European Atomic Energy Community]] in 1973, and is therefore not legally bound by the European treaty with respect to events in 1968: "When the accident occurred, Denmark was not a Member State and could not therefore be considered as being bound by the Community legislation applicable at that time. The obligations of Denmark towards the workers and the population likely to be affected by the accident could only flow from national legislation."<ref>European Parliament, 2004</ref>

The Danish government rejected a link between the accident and long-term health issues. Dr. Kaare Ulbak of the Danish National Institute of Radiation Protection said, "We have very good registers for cancer incidents and cancer mortality and we have made a very thorough investigation."((sfn|Corera 2008-11-10&nbsp;– Legacy of lost bomb)) The workers said the lack of proof was attributable to the lack of appropriate medical monitoring. As of November 2008, the case has been unsuccessful.((sfn|Corera 2008-11-10&nbsp;– Legacy of lost bomb))  A 2011 report by the Danish [[National Board of Health (Denmark)|National Board of Health]] found that "the total radiation dose for representative persons in the Thule area for plutonium contamination resulting from the 1968 Thule accident is lower than the recommended reference level, even under extreme conditions and situations."((sfn|National Board of Health 2011|p=41))

=== Scientific studies ===
[[Radioactive contamination]] occurred particularly in the marine environment. The fissile material in the weapons consisted mostly of [[uranium-235]], while the radioactive debris consists of at least two different "source terms".((efn|The "source term" is the measure of radioactive contamination released during an accident.)) Scientific monitoring of the site has been carried out periodically, with expeditions in 1968, 1970, 1974, 1979, 1984, 1991, 1997 and 2003.((sfn|Eriksson|2002|p=15))((sfn|Nielsen|Roos|2006|p=5))

A 1997 international expedition of mainly Danish and Finnish scientists carried out a comprehensive sediment sampling program in North Star Bay.((sfn|Eriksson|2002|p=13)) The main conclusions were: plutonium has not moved from the contaminated sediments into the surface water in the shelf sea; the debris has been buried to a great depth in the sediment as a result of biological activity; transfer of plutonium to [[benthic zone|benthic]] biota is low. Other research indicates that uranium is [[Leaching (chemical science)|leaching]] from the contaminated particles faster than plutonium and americium.((sfn|Eriksson|2002|p=2)) Research conducted in 2003 concluded, "Plutonium in the marine environment at Thule presents an insignificant risk to man. Most plutonium remains in the seabed under Bylot Sound far from man under relatively stable conditions and concentrations of plutonium in seawater and animals are low. However, the plutonium contamination of surface soil at [[Narsaarsuk]] could constitute a small risk to humans visiting the location if radioactive particles are resuspended in the air so that they might be inhaled."((sfn|Nielsen|Roos|2006|p=37))((sfn|Nielsen|Roos|Dahlgaard|Olsen|2009|p=94)) In 2003, 2007 and 2008, the first samples were taken on land by the [[Risø DTU National Laboratory for Sustainable Energy|Risø National Laboratory]]—the findings were published in 2011.((sfn|Ritzau 2008-11-13))((sfn|Nielsen|2008))((sfn|Nielsen|Roos|2011))

=== Literature review of declassified documents ===
A [[BBC News]] report in 2008 confirmed through declassified documents and interviews with those involved that a bomb had been lost.<ref>((cite news |first=Gordon |last=Corera |title=Mystery of lost US nuclear bomb |url=http://news.bbc.co.uk/2/hi/europe/7720049.stm |work=BBC News |date=10 November 2008))</ref><ref>((cite news |title=US left nuclear weapon under ice in Greenland |url=https://www.telegraph.co.uk/news/worldnews/europe/greenland/3439318/US-left-nuclear-weapon-under-ice-in-Greenland.html |work=The Daily Telegraph |date=11 November 2008))</ref> The Danish foreign ministry reviewed the 348&nbsp;documents that the BBC obtained in 2001 under the Freedom of Information Act. In January 2009, foreign minister [[Per Stig Møller]] commissioned a study by the [[Danish Institute for International Studies]] (DIIS) to compare the 348 documents with 317 documents released by the Department of Energy in 1994 in order to determine if the 348 documents contained any new information about an intact nuclear weapon at Thule.((sfn|Kromann|2009)) In August 2009, DIIS published its report, which contradicted the assertions of the BBC.((sfn|Christensen|2009|pp=121–125)) The report concluded that there was no missing bomb, and that the American underwater operation was a search for the [[uranium-235]] of the fissile core of a secondary.((sfn|Christensen|2009|pp=121–125)) For the first time, the report was able to present an estimate of the amount of plutonium contained in the [[plutonium pit|pits]] of the primaries.((sfn|Christensen|2009|p=54))<ref>((cite news|url=http://nyhederne.tv2.dk/article.php/id-24104886.html |date=31 July 2009 |access-date=4 August 2009 |title=Grønlandsk atombombe en skrøne |trans-title=Greenland Atomic Bomb a Hoax |publisher=[[Ritzau]] via [[TV 2 (Denmark)]] |language=da |url-status=dead |archive-url=https://web.archive.org/web/20090807150859/http://nyhederne.tv2.dk/article.php/id-24104886.html |archive-date= 7 August 2009))</ref>

==See also==
* [[List of military nuclear accidents]]
* ''[[The Idealist]]'' – 2015 Danish thriller/drama dealing with the health compensation claims
((Clear))

==Notes==
((notelist|32em))

==References==
((reflist|32em))

===Bibliography===
'''Books'''
((refbegin|32em))
* ((cite book|url = https://archive.org/details/internationalarm00blac|url-access = registration|page = [https://archive.org/details/internationalarm00blac/page/118 118]|title = International arms control|last1 = Blacker|first1 = Coit D.|last2 = Duffy|first2 = Gloria|publisher = Stanford University Press|year = 1984|isbn = 0-8047-1211-5|series = Stanford Arms Control Group))
* ((cite book|url = https://books.google.com/books?id=3iOg-t-3q1sC|title = No end in sight|last = Busch|first = Nathan E.|publisher = University Press of Kentucky|year = 2004|isbn = 0-8131-2323-2))
* ((cite book|url = https://www.diis.dk/files/media/publications/2009/diis_rp_2009-18.pdf|title = The Marshal's Baton. There is no bomb, there was no bomb, they were not looking for a bomb|last = Christensen|first = Svend Aage|work = DIIS|publisher = Danish Institute for International Studies – DIIS|year = 2009|isbn = 978-87-7605-331-4|access-date = 17 June 2011))
* ((cite book|url = https://books.google.com/books?id=MYzNtetBpFwC|title = Worst Cases|last = Clarke|first = Lee Ben|publisher = University of Chicago Press|year = 2006|isbn = 0-226-10859-7))
* ((cite book|url = https://books.google.com/books?id=ZzlNgS70OHAC|title = Weapons of Mass Destruction|last1 = Croddy|first1 = Eric|last2 = Wirtz|first2 = James J.|publisher = ABC-CLIO|year = 2005|isbn = 1-85109-490-3))
* ((cite book|title = Greenland during the cold war : Danish and American Security policy 1945–1968|translator-last = Myers|translator-first = Henry|date = 17 January 1997|publisher = Danish Institute of International Affairs (DUPI)|isbn = 87-601-6922-2|location = Copenhagen|ref = ((harvid|DUPI 1997))|lccn = 97161960))
* ((cite book|url = https://books.google.com/books?id=5Ehn6utOqLwC|title = The politics of working life|last1 = Edwards|first1 = Paul|last2 = Wajcman|first2 = Judy|publisher = Oxford University Press|year = 2005|isbn = 0-19-927190-9))
* ((cite book|url=https://archive.org/details/ProjectCrestedIce|title=Ice Investigations|last=Fristrup|first=Børge|publisher=University of Copenhagen|year=1970|isbn=87-550-0006-1|url-access=registration))
* ((cite book|url = https://books.google.com/books?id=7Fpvdv4f2cUC|title = Arms control|last = Goldblat|first = Jozef|publisher = Sage|year = 2002|isbn = 0-7619-4016-2|series = International Peace Research Institute))
* ((cite book|url = https://books.google.com/books?id=JSyv24u7iVEC|title = The Cold War|last1 = Hanhimäki|first1 = Jussi M.|last2 = Westad|first2 = Odd Arne|publisher = Oxford University Press|year = 2004|isbn = 0-19-927280-8))
* ((cite book|url = https://books.google.com/books?id=_R7Mvo4mGsoC|title = Missile defence: international, regional and national implications|last1 = Heurlin|first1 = Bertel|last2 = Rynning|first2 = Sten|publisher = Routledge|year = 2005|isbn = 0-415-36120-6))
* ((cite book|url = https://books.google.com/books?id=UY4OAAAAQAAJ|title = Denmark: A Modern History|last = Jones|first = W. Glyn|publisher = Taylor & Francis|year = 1986|isbn = 0-7099-1468-7))
* ((cite book|url = https://books.google.com/books?id=U0zIt5KPEbQC|title = B-52 Stratofortress Units in Combat 1955–73|last1 = Lake|first1 = Jon|last2 = Styling|first2 = Mark|publisher = Osprey Publishing|year = 2004|isbn = 1-84176-607-0))
* ((cite book|url = https://books.google.com/books?id=JQA9AAAAIAAJ|title = The end of the post-war era|last1 = Mayall|first1 = James|last2 = Navari|first2 = Cornelia|publisher = Cambridge University Press|year = 1980|isbn = 0-521-22698-8))
* ((cite book|title = Radioactive Particles in the Environment|last1 = Nielsen|first1 = Sven P.|last2 = Roos|first2 = Per|last3 = Dahlgaard|first3 = Henning|last4 = Olsen|first4 = Svend K.|last5 = Jernström|first5 = Jussi|last6 = Eriksson|first6 = Mats| chapter=Thule Expedition 2003 – Studies on Radioactive Contamination and Particles |publisher = Springer Publishing|year = 2009|isbn = 978-90-481-2947-8|series = NATO science for peace and security series| pages=93–109 |doi = 10.1007/978-90-481-2949-2_5| s2cid=128642838 |editor1-last = Oughton|editor1-first = Deborah H.|editor2-last = Kashparov|editor2-first = Valery))
* ((cite book|url = https://books.google.com/books?id=fJcOAAAAQAAJ&pg=PA205|title = Semialignment and Western security|last = Ørvik|first = Nils|publisher = Taylor & Francis|year = 1986|isbn = 0-7099-1951-4))
* ((cite book|title=Project Crested Ice: A joint Danish-American report on the crash near Thule Air Base on 21 January 1968 of a B-52 bomber carrying nuclear weapons|date=February 1970|publisher=Danish Atomic Energy Commission|isbn=87-550-0006-1|volume=65, pt 2|ref=((harvid|Project Crested Ice 1970: Danish Atomic Energy Commission))|journal=USAF Nuclear Safety|url-access=registration|url=https://archive.org/details/ProjectCrestedIce))
* ((cite book|url = https://books.google.com/books?id=4pV_wbOnphsC|title = The Limits of Safety|last = Sagan|first = Scott Douglas|publisher = Princeton University Press|year = 1995|isbn = 0-691-02101-5|author-link = Scott Sagan))
* ((cite book|url = https://books.google.com/books?id=safduT80AHMC|title = Atomic Audit|last = Schwartz|first = Stephen I.|publisher = Brookings Institution Press|year = 1998|isbn = 0-8157-7774-4))
* ((cite book|url = https://books.google.com/books?id=l77rP6LA8TEC|title = Explosive Effects and Applications|last1 = Zukas|first1 = Jonas A.|last2 = Walters|first2 = William P.|publisher = Springer|year = 2002|isbn = 0-387-95558-5))
((refend))

'''Journals and reports'''
((refbegin|32em))
* ((cite web|url = http://www.thulesagen.dk/thuledoc/0106883.pdf|title = AEC Observers' Interim Report of Thule Accident|date = 26 February 1968|publisher = United States Atomic Energy Commission|archive-url = https://web.archive.org/web/20081218233558/http://www.thulesagen.dk/thuledoc/0106883.pdf|access-date = 12 November 2008|archive-date = 18 December 2008))
* ((cite journal|date = Jul–Sep 1968|title = Broken Arrow&nbsp;– Thule|url = http://www.dod.mil/pubs/foi/International_security_affairs/spain/133.pdf|journal = USAF Nuclear Safety|publisher = Directorate of Nuclear Safety, United States Air Force|volume = 60|issue = 1|ref = ((harvid|Broken Arrow 1968&nbsp;– Thule))|access-date = 1 October 2013|url-status = dead|archive-url = https://web.archive.org/web/20111126220408/http://www.dod.mil/pubs/foi/International_security_affairs/spain/133.pdf|archive-date = 26 November 2011|df = dmy-all))
* ((cite journal|last=Dresser|first=Col D.S.|date=January 1970|title=Host Base Support|url=http://www.risoe.dk/rispubl/NUK/nukpdf/ris-r-213_p30-46.pdf|journal=USAF Nuclear Safety|location=Thule Air Base|access-date=24 April 2009|url-status=dead|archive-url=https://web.archive.org/web/20070609220339/http://www.risoe.dk/rispubl/NUK/nukpdf/ris-r-213_p30-46.pdf|archive-date=9 June 2007))
* ((cite thesis|type=PhD|isbn=87-550-3007-6|last=Eriksson|first=Mats|date=April 2002|title=On Weapons Plutonium in the Arctic Environment (Thule, Greenland)|url=http://www.risoe.dk/rispubl/NUK/nukpdf/ris-r-1321.pdf|location=Risø National Laboratory, Roskilde, Denmark|publisher=[[Lund University]]|id=Risø–R–1321(EN)|access-date=17 June 2011|url-status=dead|archive-url=https://web.archive.org/web/20090327090445/http://www.risoe.dk/rispubl/NUK/nukpdf/ris-r-1321.pdf|archive-date=27 March 2009))
* ((cite journal|last=Hunziker|first=R.O.|date=Jan–Mar 1970|title=The Commander's Point of View|url=http://www.dtic.mil/dtic/tr/fulltext/u2/701493.pdf|journal=USAF Nuclear Safety|volume=65|issue=2|pages=12–24|ref=((harvid|Hunziker))|access-date=3 November 2011))((dead link|date=June 2022|bot=medic))((cbignore|bot=medic))
* ((cite web|url=http://www.si-folkesundhed.dk/upload/thule.pdf|title=Register study of mortality and cancer incidence among Thule workers|last1=Juel|first1=Knud|last2=Engholm|first2=Gerda|year=2005|publisher=National Institute of Public Health & Cancer Society|location=Denmark|language=da|last3=Storm|first3=Hans|access-date=17 June 2011|url-status=dead|archive-url=https://web.archive.org/web/20110719131837/http://www.si-folkesundhed.dk/upload/thule.pdf|archive-date=19 July 2011))
* ((cite journal|last = Kidder|first = Ray E.|date = April 1991|title = Safety no Barrier to Test Ban|url = https://books.google.com/books?id=cwwAAAAAMBAJ&pg=PA32|journal = Bulletin of the Atomic Scientists|volume = 47|issue = 3|page = 32|doi = 10.1080/00963402.1991.11459959|bibcode = 1991BuAtS..47c..32K))
* ((cite book|last1=Nielsen|first1=Sven P.|last2=Roos|first2=Per|date=2006|title=Thule-2003&nbsp;– Investigation of Radioactive Contamination|url=http://iis-03.risoe.dk/netacgi/nph-brs.exe?d=PUBL&s1=SPNI.meid.+and+(b.trc.+or+c.trc.+or+d.trc.)&pg1=ALL&co1=and&s2=&pg2=ALL&co2=and&s3=0&co3=and&s4=@SAAR%3E%3D1991&co4=and&s5=0&l=20&co5=and&s6=@SAAR%3E%3D1991%3C%3D2006&p=1&Sect1=PUBNEKS&Sect2=TXT&u=%2Fnetahtml%2Frisoe%2Fpubl_uk.htm&op1=AND&r=0&f=S|archive-url=https://web.archive.org/web/20110719130901/http://iis-03.risoe.dk/netacgi/nph-brs.exe?d=PUBL&s1=SPNI.meid.+and+%28b.trc.+or+c.trc.+or+d.trc.%29&pg1=ALL&co1=and&s2=&pg2=ALL&co2=and&s3=0&co3=and&s4=%40SAAR%3E%3D1991&co4=and&s5=0&l=20&co5=and&s6=%40SAAR%3E%3D1991%3C%3D2006&p=1&Sect1=PUBNEKS&Sect2=TXT&u=%2Fnetahtml%2Frisoe%2Fpubl_uk.htm&op1=AND&r=0&f=S|url-status=dead|archive-date=19 July 2011|location=Roskilde|publisher=Radiation Research Department, Risø National Laboratory|isbn=87-550-3508-6|access-date=17 June 2011))
* ((cite web|url = http://www.thulesundhed.dk/Webnodes/download/268|title = Thule Field Report|last = Nielsen|first = Sven P.|date = 17 November 2008|publisher = Risø National Laboratory|id = CVR-nr. DK 30 06 09 46|access-date = 17 June 2011|archive-url = https://web.archive.org/web/20090409071316/http://www.thulesundhed.dk/Webnodes/download/268|archive-date = 9 April 2009))
* ((cite report
| url = http://orbit.dtu.dk/en/publications/id(c3b7244a-5c9d-49a1-84aa-4397903103ec).html
| title = Thule-2007 – Investigation of Radioactive Pollution on Land
| last1 = Nielsen
| first1 = Sven Poul
| last2 = Roos
| first2 = Per
| date = 10 October 2011
| publisher = Risø National Laboratory for Sustainable Energy
| location = Roskilde
| isbn = 978-87-550-3913-1
| id = Risø-R-1781(EN)
))
* ((cite web|url = http://community.marines.mil/news/publications/Documents/MCO%203504.2.pdf|title = Operations Event/Incident Report (OPREP-3) Reporting|last = Natonski|first = R. F.|date = 8 June 2007|publisher = United States Navy|id = MCO 3504.2|access-date = 10 January 2013))
* ((cite magazine|date = 17 May 1961|title = SAC's Deadly Daily Dozen|url = http://www.time.com/time/magazine/article/0,9171,894429-2,00.html|archive-url = https://web.archive.org/web/20090618071250/http://www.time.com/time/magazine/article/0,9171,894429-2,00.html|url-status = dead|archive-date = 18 June 2009|magazine = Time|issn = 0040-781X|ref = ((harvid|Time 1961&nbsp;– Deadly Daily Dozen))|access-date = 17 June 2011))
* ((cite web|url = http://www.thulesagen.dk/thuledoc/0107059.pdf|title = Thule Status Report|date = 10 September 1968|publisher = United States Atomic Energy Commission|ref = ((harvid|Thule Status Report 1968))|archive-url = https://web.archive.org/web/20081218233555/http://www.thulesagen.dk/thuledoc/0107059.pdf|access-date = 18 November 2008|archive-date = 18 December 2008))
* ((cite report
 | url = http://www.sst.dk/publ/Publ2011/SIS/Thule/Thulerap_en.pdf
 | title = The Thule Accident: Assessment of Radiation Doses from Terrestrial Radioactive Contamination
 | date = 24 November 2011
 | publisher = National Board of Health
 | location = Copenhagen
 | isbn = 978-87-7104-229-0
 | ref = ((harvid|National Board of Health 2011))
 | access-date = 12 January 2013
 | archive-url = https://web.archive.org/web/20130112105842/http://www.sst.dk/publ/Publ2011/SIS/Thule/Thulerap_en.pdf
 | archive-date = 12 January 2013
 | url-status = dead
 ))
* ((cite report
 | url = http://dlstg.dtic.mil/pubs/foi/operation_and_plans/NuclearChemicalBiologicalMatters/DocsConcerningThuleAccident.pdf
 | title = Joint Committee on Atomic Energy
 | date = 28 March 1968
 | publisher = [[United States Department of Defense]]
 | location = Washington
 | ref = ((harvid|Joint Committee on Atomic Energy 1968))
 | access-date = 15 January 2013
 ))((dead link|date=June 2022|bot=medic))((cbignore|bot=medic)) [http://commons.wikimedia.org/w/index.php?title=File%3ADocuments_Concerning_Thule_Accident.pdf Alt URL]
* ((cite journal|date=Jan–Mar 1970|title=The Flight of HOBO 28|url=http://www.risoe.dtu.dk/rispubl/NUK/nukpdf/ris-r-213_p1-29.pdf|journal=USAF Nuclear Safety|location=Nebraska|publisher=Danish Atomic Energy Commission|volume=65|issue=2|ref=((harvid|The Flight of HOBO 28))|access-date=21 January 2013|author=Strategic Air Command|url-status=dead|archive-url=https://web.archive.org/web/20120330162940/http://www.risoe.dtu.dk/rispubl/NUK/nukpdf/ris-r-213_p1-29.pdf|archive-date=30 March 2012))
((refend))

'''Online sources'''
((refbegin|32em))
* ((cite web|url = http://www.historisktidsskrift.dk/summary/101_109.html|title = A Policy of the Utmost Flexibility: Danish Nuclear Weapons Policy 1956–1960|last1 = Agger|first1 = Jonathan Søborg|last2 = Wolsgård|first2 = Lasse=|publisher = Danish Historical Association|work = historisktidsskrift.dk|access-date = 10 May 2009))
* ((cite web|url = http://www.nukestrat.com/dk/State012368.PDF|title = B-52 Crash|date = 24 January 1968|publisher = [[National Military Command Center]] via nukestrat.com|location = Pentagon|ref = ((harvid|B-52 Crash 1968&nbsp;– NMCC))|access-date = 12 April 2009|archive-url = https://web.archive.org/web/20080907183721/http://www.nukestrat.com/dk/State012368.PDF|archive-date = 7 September 2008))
* ((cite web|url=http://www.thulesagen.dk/thuledoc/0075943.pdf|title=B-52 Crash at Thule Air Base|date=22 January 1968|publisher=[[United States Atomic Energy Commission]]|ref=((harvid|B-52 Crash at Thule Air Base 1968&nbsp;– USAEC))|access-date=13 November 2008|url-status=dead|archive-url=https://web.archive.org/web/20110725214623/http://www.thulesagen.dk/thuledoc/0075943.pdf|archive-date=25 July 2011))
* ((cite news|url=http://cndyorks.gn.apc.org/yspace/articles/greenland3.htm|title=Greenlanders Wary of a New Role in U.S. Defenses|last=Brooke|first=James|date=18 September 2000|work=[[The New York Times]]|access-date=11 November 2008|archive-url=https://web.archive.org/web/20090409005559/http://cndyorks.gn.apc.org/yspace/articles/greenland3.htm|archive-date=9 April 2009))
* ((cite news|url = http://news.bbc.co.uk/2/hi/science/nature/7720466.stm|title = Radioactive legacy of 'lost bomb'|last = Corera|first = Gordon|date = 10 November 2008|work = BBC News|ref = ((harvid|Corera 2008-11-10&nbsp;– Legacy of lost bomb))|author-link = Gordon Corera|access-date = 17 June 2011))
* ((cite news|url = http://news.bbc.co.uk/2/hi/europe/7720049.stm|title = Mystery of lost US nuclear bomb|last = Corera|first = Gordon|date = 10 November 2008|work = BBC News|ref = ((harvid|Corera 2008-11-10&nbsp;– Mystery of lost bomb))|author-link = Gordon Corera|access-date = 17 June 2011))
* ((rs|date=March 2023)) ((cite web|url = http://www.globalsecurity.org/wmd/ops/broken-arrow.htm|title = Broken Arrows|date = 28 April 2005|publisher = GlobalSecurity.org|ref = ((harvid|Global Security 2005&nbsp;– Broken Arrows))|access-date = 17 June 2011))
* ((cite web|url=http://www.nautilus.org/archives/library/security/foia/DKhansen57.html|title=Danish Prime Minister Gives Tacit Go-Ahead For U.S. Nuclear Weapons in Greenland|last=Hansen|first=H. C.|author-link=H. C. Hansen|date=16 November 1957|publisher=The Nautilus Institute|access-date=20 March 2009|archive-url=https://web.archive.org/web/20071106145717/http://www.nautilus.org/archives/library/security/foia/DKhansen57.html|archive-date=6 November 2007))
* ((cite web|url = http://www.nukestrat.com/dk/gr.htm|title = Denmark's Thulegate|last = Kristensen|first = Hans M.|year = 2004|publisher = Nuclear Information Project|access-date = 21 April 2009))
* ((cite web|url=http://www.nautilus.org/archives/nukepolicy/Denmark/index.html|title=Secrecy on a Sliding Scale: U.S. Nuclear Weapons Deployments And Danish Non-Nuclear Policy|last=Kristensen|first=Hans M.|date=20 October 1999|publisher=The Nautilus Institute|access-date=20 March 2009|archive-url=https://web.archive.org/web/20071231130921/http://www.nautilus.org/archives/nukepolicy/Denmark/index.html|archive-date=31 December 2007))
* ((cite news|url=http://politiken.dk/politik/ECE624896/arktisk-atombombe-skal-undersoeges-igen/|title=Arctic atomic bomb should be examined again|last=Kromann|first=Hans Christian|date=7 January 2009|newspaper=[[Politiken]]|access-date=17 June 2011|url-status=dead|archive-url=https://web.archive.org/web/20110607014752/http://politiken.dk/politik/ECE624896/arktisk-atombombe-skal-undersoeges-igen/|archive-date=7 June 2011))
* ((cite news|url = http://news.bbc.co.uk/2/hi/americas/878907.stm|title = Nuclear bomb 'lost near Greenland'|last = Leyne|first = Jon|date = 13 August 2000|work = BBC News|access-date = 16 June 2011))
* ((cite web|url=http://www.greenpeace.org/raw/content/international/press/reports/the-greenpeace-book-of-the-nuc.pdf|title=The Greenpeace book of the nuclear age; The hidden history – the human cost|last=May|first=John|year=1989|publisher=[[Greenpeace]] Books|page=205|access-date=19 April 2009|archive-url=https://web.archive.org/web/20090410224652/http://www.greenpeace.org/raw/content/international/press/reports/the-greenpeace-book-of-the-nuc.pdf|archive-date=10 April 2009|url-status=live))
* ((cite web|url = http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA283578&Location=U2&doc=GetTRDoc.pdf|title = Project Crested Ice|last = McElwee|first = Captain Robert E.|date = March 1968|publisher = United States Navy|archive-url = https://web.archive.org/web/20090618212435/http://www.dtic.mil/cgi-bin/GetTRDoc?AD=ADA283578&Location=U2&doc=GetTRDoc.pdf|archive-date = 18 June 2009|url-status = dead|access-date = 14 November 2008))
* ((cite news|url = http://news.bbc.co.uk/2/hi/europe/6647421.stm|title = Denmark challenged over B52 crash|last = Mulvey|first = Stephen|date = 11 May 2007|work = [[BBC News]]|access-date = 16 June 2011))
* ((cite news|url = http://politiken.dk/indland/article597710.ece|title = Risø examine radiation at the Thule base|date = 13 November 2008|agency = [[Ritzau]]|language = da|ref = ((harvid|Ritzau 2008-11-13))|access-date = 17 June 2011))
* [http://www.europarl.europa.eu/meetdocs/2004_2009/documents/cm/530/530757/530757en.pdf ''Petition 720/2002 by Jeffrey Carswell''], Committee on Petitions, European Parliament, 2004
* [http://www.europarl.europa.eu/meetdocs/2004_2009/documents/cm/650/650924/650924en.pdf ''Petition 720/2002 by Jeffrey Carswell''], Committee on Petitions, European Parliament, 2007
* ((cite conference|conference = AIAA/ASME/SAE/ASEE joint propulsion conference, Cleveland, OH|url = http://www.osti.gov/bridge/servlets/purl/671923-JYRvMV/webviewable/671923.pdf|title = The History of Nuclear Weapon Safety Devices|last1 = Plummer|first1 = David W.|last2 = Greenwood|first2 = William H.|date = June 1998|publisher = Sandia National Laboratories|location = Albuquerque))
* ((cite book |first=Steven |last=Pomeroy |url=http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=ADA452153&Location=U2&doc=GetTRDoc.pdf |title=Echos That Never Were: American Mobile Intercontinental Ballistic Missiles, 1956–1983 |publisher=US Air Force |date=14 April 2006 |access-date=23 October 2011 |archive-url=https://web.archive.org/web/20120406205615/http://stinet.dtic.mil/cgi-bin/GetTRDoc?AD=ADA452153&Location=U2&doc=GetTRDoc.pdf |archive-date=6 April 2012 |url-status=dead ))
* ((cite web|url=http://www.gwu.edu/~nsarchiv/nukevault/ebb267/03.pdf|title=Project Crested Ice: The Thule Accident|date=23 April 1969|publisher=History & Research Division, Strategic Air Command (via [[National Security Archive]])|ref=((harvid|Project Crested Ice 1969: The Thule Accident))|access-date=17 June 2011|archive-url=https://web.archive.org/web/20090424235048/http://www.gwu.edu/~nsarchiv/nukevault/ebb267/03.pdf|archive-date=24 April 2009|url-status=live))
* ((cite web|url=http://www.arcus.org/publications/downloads/greenland.pdf|title=Greenland: Security Perspectives|last1=Taagholt|first1=Jørgen|last2=Hansen|first2=Jens Claus|year=2001|publisher=Arctic Research Consortium of the United States|location=Fairbanks, Alaska|pages=35–43|others=Daniel Lufkin (translator)|archive-url=https://web.archive.org/web/20101223005129/http://www.arcus.org/publications/downloads/greenland.pdf|archive-date=23 December 2010|url-status=live))
* ((cite web|url = http://airforcemedicine.afms.mil/latestnews/body.pdf|title = Thule Nuclear Weapons Accident: Dose Evaluation Report|date = April 2001|publisher = [[United States Air Force Medical Service]]|ref = ((harvid|Dose Evaluation Report 2001))|archive-url = https://web.archive.org/web/20120217071618/http://airforcemedicine.afms.mil/latestnews/body.pdf|archive-date = 17 February 2012|access-date = 17 June 2011))
* ((cite web|url=https://eed.llnl.gov/ans/2002/vantine/vantine_ans_2002.pdf|title=Relevance of Nuclear Weapons Clean-up Experience to Dirty Bomb Response|last1=Vantine|first1=Harry C.|last2=Crites|first2=Thomas R.|date=26 March 2003|publisher=[[Lawrence Livermore National Laboratory]]|archive-url=https://web.archive.org/web/20090327090415/https://eed.llnl.gov/ans/2002/vantine/vantine_ans_2002.pdf|archive-date=27 March 2009))
((refend))

==Further reading==
* ((cite journal|last=Aarkrog|first=Asker|date=January 1970|title=Radio-Ecological Investigations|url=http://www.risoe.dk/rispubl/NUK/nukpdf/ris-r-213_p79-88.pdf|journal=USAF Nuclear Safety|publisher=Danish Atomic Energy Commission|access-date=17 June 2011|url-status=dead|archive-url=https://web.archive.org/web/20070609221011/http://www.risoe.dk/rispubl/NUK/nukpdf/ris-r-213_p79-88.pdf|archive-date=9 June 2007))
* ((cite book
  | last = Brink
  | first = Poul
  | year = 1997
  | title = Thule-Sagen, Løgnens Univers
  | language = da
  | publisher = Aschehoug
  | isbn = 87-11-15045-9
  | url = https://books.google.com/books?id=VYI3AAAACAAJ
  ))
* ((Cite web |last=Jorgensen |first=Timothy J. |date=17 January 2018 |title=50 years ago, a US military jet crashed in Greenland – with 4 nuclear bombs on board |publisher=The Conversation US, Inc. |location=Boston, MA|url=https://theconversation.com/50-years-ago-a-us-military-jet-crashed-in-greenland-with-4-nuclear-bombs-on-board-87155 |access-date=24 January 2018 ))
* ((cite journal|last = Juel|first = Knud|year = 1992|title = The Thule Episode Epidemiological Followup After the Crash of a B-52 Bomber in Greenland: Registry Linkage, Mortality, Hospital Admissions|journal = Journal of Epidemiology and Community Health|location = Copenhagen|publisher = Danish Institute for Clinical Epidemiology|volume = 46|issue = 4|pages = 336–9|doi = 10.1136/jech.46.4.336|pmc = 1059595|pmid = 1431702))
* ((cite web|url=http://www.nautilus.org/archives/library/security/foia/White012368.html|title=Following Bomber Crash, U.S. Copenhagen Embassy Urges State Department To Lie About Flight Route|last=Kristensen|first=Hans M.|date=23 January 1968|publisher=US State Department via Nautilus.org|access-date=13 April 2009|archive-url=https://web.archive.org/web/20090618073758/http://www.nautilus.org/archives/library/security/foia/White012368.html|archive-date=18 June 2009|url-status=dead))
* ((cite book
  | last1 = Oskins
  | first1 = James C.
  | last2 = Maggelet
  | first2 = Michael H.
  | year = 2008
  | title = Broken Arrow&nbsp;– The Declassified History of U.S. Nuclear Weapons Accidents
  | publisher = [[Lulu (company)|Lulu]]
  | isbn = 978-1-4357-0361-2
  | url = https://books.google.com/books?id=gi7HARO8vTcC
  | access-date = 17 June 2011
  ))
* ((cite journal|date = Sep–Oct 1966|title = Broken Arrow&nbsp;– Palomares, Spain|url = http://www.dod.mil/pubs/foi/International_security_affairs/spain/133.pdf|journal = USAF Nuclear Safety|publisher = Directorate of Nuclear Safety, United States Air Force|volume = 52|ref = ((harvid|Broken Arrow 1966&nbsp;– Palomares))|access-date = 1 October 2013|url-status = dead|archive-url = https://web.archive.org/web/20111126220408/http://www.dod.mil/pubs/foi/International_security_affairs/spain/133.pdf|archive-date = 26 November 2011|df = dmy-all))
* ((cite web|url = https://history.state.gov/historicaldocuments/frus1964-68v12/ch1|title = Foreign Relations of the United States 1964–1968, Volume XII, Western Europe: Denmark|publisher = [[United States Department of State]]|ref = ((harvid|Foreign Relations of the United States 1964–1968: Denmark))|access-date = 12 November 2008))
* ((cite book|url = http://www.thulesundhed.dk/Webnodes/download/264|title = International Peer Review of the Technical Contentof the Project Proposal 'Thule 2007 – Investigation of Radioactive Contamination on Land'|date = 3 March 2008|publisher = International Atomic Energy Commission|location = Vienna|ref = ((harvid|IAEC: Thule 2007))|access-date = 17 June 2011|archive-url = https://web.archive.org/web/20110616104238/http://www.thulesundhed.dk/Webnodes/download/264|url-status = dead <!-- it's a pdf but wo/".pdf" ;) -->|archive-date = 16 June 2011))
* ((cite magazine|date = March 2009|title = The Worst Nuclear Disasters|url = http://www.time.com/time/photogallery/0,29307,1887705_1862266,00.html|archive-url = https://web.archive.org/web/20090330062255/http://www.time.com/time/photogallery/0,29307,1887705_1862266,00.html|url-status = dead|archive-date = 30 March 2009|magazine = Time|issn = 0040-781X|ref = ((harvid|Time 2009&nbsp;– Worst Nuclear Disasters))|access-date = 17 June 2011))

== External links ==
((Commons category|Thule accident))
((external media
| float  = right
| width  =
| image1 = [http://www.thuleforum.com/rose/index_1.htm 1968 photos of Thule Air Base and surrounds]
| image2 = [http://www.diis.dk/sw82076.asp Underwater photos from the Star III submarine]
))
* [https://web.archive.org/web/20130718172040/http://thulesagen.com/ Documentation and photos] ((in lang|da))
* [https://web.archive.org/web/20081218233551/http://www.afrri.usuhs.mil/outreach/reports/pdf/SP86-2.pdf DoD Mishaps] by the [[Armed Forces Radiobiology Research Institute]]
* [http://news.bbc.co.uk/2/hi/7720671.stm Declassified US government video of clean-up operation] BBC
* [http://www.sis.dk/ National Institute for Radiation Protection (Denmark)] ((in lang|da))

((Featured article))
((Aviation accidents and incidents in 1968))
((Aviation accidents and incidents in Denmark))
((Authority control))

((DEFAULTSORT:Thule Air Base B-52 crash))
[[Category:1968 in Denmark]]
[[Category:1968 in Greenland]]
[[Category:1968 in military history]]
[[Category:1968 in the United States]]
[[Category:1995 in Denmark]]
[[Category:Accidents and incidents involving the Boeing B-52 Stratofortress]]
[[Category:Aircraft fires]]
[[Category:Aviation accidents and incidents caused by in-flight fires]]
[[Category:Aviation accidents and incidents in 1968]]
[[Category:Aviation accidents and incidents in Greenland]]
[[Category:Aviation accidents and incidents involving nuclear weapons]]
[[Category:Cold War military history of the United States]]
[[Category:Greenland–United States relations]]
[[Category:Denmark–United States relations]]
[[Category:Military in the Arctic]]
[[Category:Political scandals in Denmark]]
[[Category:Military scandals]]
[[Category:January 1968 events in North America]]

Pages transcluded onto the current version of this page (help):

1968 Thule Air Base B-52 crash (edit)
Template:Anchor (view source) (template editor protected)
Template:Authority control (view source) (template editor protected)
Template:Aviation accidents and incidents (view source) (semi-protected)
Template:Aviation accidents and incidents in 1968 (edit)
Template:Aviation accidents and incidents in Denmark (edit)
Template:CURRENTISOYEAR (view source) (semi-protected)
Template:Category handler (view source) (protected)
Template:Cbignore (view source) (template editor protected)
Template:Citation needed span (view source) (template editor protected)
Template:Cite book (view source) (protected)
Template:Cite conference (view source) (protected)
Template:Cite journal (view source) (protected)
Template:Cite magazine (view source) (protected)
Template:Cite news (view source) (protected)
Template:Cite report (view source) (template editor protected)
Template:Cite thesis (view source) (template editor protected)
Template:Cite web (view source) (protected)
Template:Clear (view source) (protected)
Template:Cnspan (edit)
Template:Commons category (view source) (template editor protected)
Template:Convert (view source) (template editor protected)
Template:Coord (view source) (protected)
Template:DMCA (view source) (template editor protected)
Template:Dated maintenance category (view source) (template editor protected)
Template:Dated maintenance category (articles) (view source) (template editor protected)
Template:Dead link (view source) (template editor protected)
Template:Delink (view source) (protected)
Template:Div col (view source) (template editor protected)
Template:Div col/styles.css (view source) (template editor protected)
Template:Div col end (view source) (template editor protected)
Template:Efn (view source) (template editor protected)
Template:External media (view source) (template editor protected)
Template:FULLROOTPAGENAME (view source) (template editor protected)
Template:Featured article (view source) (template editor protected)
Template:Fix (view source) (protected)
Template:Fix-span (view source) (template editor protected)
Template:Fix/category (view source) (protected)
Template:Format price (view source) (template editor protected)
Template:Format price/digits (view source) (template editor protected)
Template:Formatprice (view source) (protected)
Template:Harvid (view source) (template editor protected)
Template:Hlist/styles.css (view source) (protected)
Template:IPAc-en (view source) (template editor protected)
Template:In lang (view source) (template editor protected)
Template:Inflation (view source) (template editor protected)
Template:Inflation/US (view source) (template editor protected)
Template:Inflation/US/dataset (view source) (template editor protected)
Template:Inflation/US/startyear (view source) (template editor protected)
Template:Inflation/year (view source) (template editor protected)
Template:Infobox (view source) (template editor protected)
Template:Infobox aircraft occurrence (view source) (template editor protected)
Template:Isnumeric (view source) (template editor protected)
Template:Lang-da (view source) (template editor protected)
Template:Location map+ (view source) (template editor protected)
Template:Location map~ (view source) (template editor protected)
Template:Main other (view source) (protected)
Template:Navbox (view source) (template editor protected)
Template:Nbsp (view source) (protected)
Template:Notelist (view source) (template editor protected)
Template:Nowrap (view source) (protected)
Template:Ns has subpages (view source) (protected)
Template:Pagetype (view source) (protected)
Template:Plainlist/styles.css (view source) (protected)
Template:Pp-move (view source) (template editor protected)
Template:Pp-move-indef (view source) (template editor protected)
Template:Refbegin (view source) (template editor protected)
Template:Refbegin/styles.css (view source) (template editor protected)
Template:Refend (view source) (template editor protected)
Template:Reflist (view source) (protected)
Template:Reflist/styles.css (view source) (protected)
Template:Replace (view source) (protected)
Template:Rs (view source) (template editor protected)
Template:SDcat (view source) (protected)
Template:Sfn (view source) (template editor protected)
Template:SfnRef (view source) (template editor protected)
Template:Short description (view source) (protected)
Template:Short description/lowercasecheck (view source) (protected)
Template:Side box (view source) (template editor protected)
Template:Sister project (view source) (template editor protected)
Template:Spaces (view source) (protected)
Template:Start date (view source) (template editor protected)
Template:Template other (view source) (protected)
Template:Top icon (view source) (template editor protected)
Template:Unreliable source? (view source) (template editor protected)
Template:Use dmy dates (view source) (template editor protected)
Module:Aligned dates list (view source) (semi-protected)
Module:Anchor (view source) (template editor protected)
Module:Arguments (view source) (protected)
Module:Authority control (view source) (template editor protected)
Module:Authority control/config (view source) (template editor protected)
Module:Category handler (view source) (protected)
Module:Category handler/blacklist (view source) (protected)
Module:Category handler/config (view source) (protected)
Module:Category handler/data (view source) (protected)
Module:Category handler/shared (view source) (protected)
Module:Check for unknown parameters (view source) (protected)
Module:Citation/CS1 (view source) (protected)
Module:Citation/CS1/COinS (view source) (protected)
Module:Citation/CS1/Configuration (view source) (protected)
Module:Citation/CS1/Date validation (view source) (protected)
Module:Citation/CS1/Identifiers (view source) (protected)
Module:Citation/CS1/Utilities (view source) (protected)
Module:Citation/CS1/Whitelist (view source) (protected)
Module:Citation/CS1/styles.css (view source) (protected)
Module:Convert (view source) (template editor protected)
Module:Convert/data (view source) (template editor protected)
Module:Convert/text (view source) (template editor protected)
Module:Coordinates (view source) (protected)
Module:Coordinates/styles.css (view source) (protected)
Module:DecodeEncode (view source) (template editor protected)
Module:Delink (view source) (protected)
Module:Disambiguation/templates (view source) (protected)
Module:Effective protection expiry (view source) (protected)
Module:Effective protection level (view source) (protected)
Module:File link (view source) (template editor protected)
Module:Footnotes (view source) (template editor protected)
Module:Footnotes/anchor id list (view source) (template editor protected)
Module:Footnotes/anchor id list/data (view source) (template editor protected)
Module:Footnotes/whitelist (view source) (template editor protected)
Module:IPAc-en (view source) (template editor protected)
Module:IPAc-en/data (view source) (template editor protected)
Module:IPAc-en/phonemes (view source) (template editor protected)
Module:IPAc-en/pronunciation (view source) (template editor protected)
Module:In lang (view source) (template editor protected)
Module:Infobox (view source) (template editor protected)
Module:Infobox/styles.css (view source) (template editor protected)
Module:InfoboxImage (view source) (template editor protected)
Module:Lang (view source) (template editor protected)
Module:Lang/ISO 639 synonyms (view source) (template editor protected)
Module:Lang/data (view source) (template editor protected)
Module:Language/data/iana languages (view source) (template editor protected)
Module:Language/data/iana regions (view source) (template editor protected)
Module:Language/data/iana scripts (view source) (template editor protected)
Module:Language/data/iana suppressed scripts (view source) (template editor protected)
Module:Language/data/iana variants (view source) (template editor protected)
Module:Location map (view source) (template editor protected)
Module:Location map/data/Greenland (view source) (semi-protected)
Module:Location map/multi (view source) (template editor protected)
Module:Location map/styles.css (view source) (template editor protected)
Module:Math (view source) (protected)
Module:Namespace detect/config (view source) (protected)
Module:Namespace detect/data (view source) (protected)
Module:Navbar (view source) (protected)
Module:Navbar/configuration (view source) (protected)
Module:Navbar/styles.css (view source) (protected)
Module:Navbox (view source) (template editor protected)
Module:Navbox/configuration (view source) (template editor protected)
Module:Navbox/styles.css (view source) (template editor protected)
Module:Ns has subpages (view source) (protected)
Module:Pagetype (view source) (protected)
Module:Pagetype/config (view source) (protected)
Module:Pagetype/disambiguation (view source) (protected)
Module:Pagetype/rfd (view source) (template editor protected)
Module:Pagetype/setindex (view source) (protected)
Module:Pagetype/softredirect (view source) (protected)
Module:Protection banner (view source) (template editor protected)
Module:Protection banner/config (view source) (template editor protected)
Module:SDcat (view source) (protected)
Module:Side box (view source) (template editor protected)
Module:Side box/styles.css (view source) (template editor protected)
Module:String (view source) (protected)
Module:TableTools (view source) (protected)
Module:Unicode data (view source) (template editor protected)
Module:Unsubst (view source) (protected)
Module:WikidataIB (view source) (template editor protected)
Module:WikidataIB/nolinks (view source) (template editor protected)
Module:WikidataIB/titleformats (view source) (template editor protected)
Module:Wikitext Parsing (view source) (protected)
Module:Yesno (view source) (protected)

Return to 1968 Thule Air Base B-52 crash.

Retrieved from "https://en.wikipedia.org/wiki/1968_Thule_Air_Base_B-52_crash"