View source for SM-65 Atlas

{{Short description|First operational American intercontinental ballistic missile}}
{{Redirect|Atlas Rocket|the rocket family|Atlas (rocket family)}}
{{More citations needed|date=October 2020}}
{{Use American English|date=November 2020}}
{{Use dmy dates|date=April 2017}}
{{Infobox rocket
| image              = Atlas 2E Ballistic Missile.jpg
| caption            = Atlas 2E missile, San Diego Aerospace Museum

<!----Core parameters (required)---->
| name               = B-65/SM-65/CGM-16/HGM-16 Atlas
| function           = [[Intercontinental Ballistic Missile]] (ICBM)
| manufacturer       = [[Convair]] / [[General Dynamics]]
| country-origin     = United States

<!----Dimensions (required)---->
|height         = {{convert|75|ft|10|in|abbr=on}}<br />{{convert|85|ft|6|in|abbr=on}} in ICBM configuration
|diameter       = {{convert|10|ft|m|abbr=on}}
|width          = {{convert|16|ft|m|abbr=on}}
|mass           = {{convert|260000|lb|-2|abbr=on}}
|stages         = [[#'Stage-and-a-half'|1½]]

<!----Associated rockets (optional)---->
|family        = [[Atlas (rocket)|Atlas]]
|derivatives   = <!--derived rockets, optional-->
|comparable    = <!--similar, unrelated rockets, optional-->

<!----Launch history (required)---->
|status        = Retired April 1965
|sites         = <!--launch centres and pads, required-->
|launches      = 24
|success       = 13
|fail          = 11
|partial       = <!--total number of launches resulting in partial failure (e.g. incorrect orbit but still usable), optional-->
|other_outcome = <!--number of launches with unknown outcomes (or in progress), optional-->
|first         = 11 June 1957
|last          = 24 August 1959

<!--Stages/boosters (optional)-->
|stagedata     = <!--insert one of the following templates for each stage:-->

{{Infobox rocket/stage
  |type       =  booster
  |stageno    =  <!--position of stage in rocket, spelled out (eg. First, Second, etc), required-->
  |number     =  1
  |length     =  <!--length of a single booster/stage in metres, optional, use {{convert}}-->
  |diameter   =  <!--diameter of a single booster/stage, optional in metres, use {{convert}}-->
  |width      =  <!--width of a single booster/stage if not axisymmetric, optional, use {{convert}}-->
  |empty      =  <!--empty mass of a single booster/stage in kilograms, optional, use {{convert}}-->
  |gross      =  <!--gross (fuelled) mass of a single booster/stage, optional-->
  |engines    =  2
  |thrust     =  {{convert|300000|lbf|kN|abbr=on}}<br /> Atlas D
  |total      =  {{convert|360000|lbf|kN|abbr=on}}<br /> Atlas D
  |SI         =  <!--specific impulse of an individual booster/stage, in secs, optional-->
  |burntime   =  <!--burn time, required-->
  |fuel       =  [[RP-1]]/[[LOX]]
  }}
{{Infobox rocket/stage
  |type       =  stage
  |stageno    =  First
  |length     =  <!--length of a single booster/stage in metres, optional, use {{convert}}-->
  |diameter   =  <!--diameter of a single booster/stage, optional in metres, use {{convert}}-->
  |empty      =  <!--empty mass of a single booster/stage in kilograms, optional, use {{convert}}-->
  |gross      =  <!--gross (fuelled) mass of a single booster/stage, optional-->
  |engines    =  1
  |thrust     =  {{convert|60000|lbf|kN|abbr=on}}<br /> Atlas D
  |SI         =  <!--specific impulse of an individual booster/stage, in secs, optional-->
  |burntime   =  <!--burn time, required-->
  |fuel       =  [[RP-1]]/[[LOX]]
}}
}}
{{Infobox weapon
| name               = Convair X-11 / SM-65 Atlas
| image              = 
| image_size         = 300
| alt                = 
| caption            = 
| type               = 
| origin             = United States

<!-- Type selection -->| is_ranged          = 
| is_bladed          = 
| is_explosive       = 
| is_artillery       = 
| is_vehicle         = 
| is_missile         = y
| is_UK              = <!-- Service history -->
| service            = 1959–1964
| used_by            = [[United States Air Force]]
| wars               = [[Cold War]]
<!-- Production history -->| designer           = 
| design_date        = 
| manufacturer       = [[Convair]]
| unit_cost          = 
| production_date    = 
| number             = 
| variants           = <!-- General specifications -->
| spec_label         = 
| mass               = {{convert|255950|lb|-1|abbr=on}} for Atlas D w/o payload, {{convert|260000|lb|-2|abbr=on}} for Atlas D with Mk 2/3 RV and W49 warhead, {{convert|268000|lb|-1|abbr=on}} for Atlas E&F with Mk 4 RV and W38 warhead
| length             = {{convert|75|ft|1|in|abbr=on}} with Mk 2 re-entry vehicle, {{convert|82|ft|6|in|abbr=on}} with Mk 3
| part_length        = 
| width              = {{convert|16|ft|1|in|abbr=on}}
| height             = 
| diameter           = {{convert|10|ft|0|in|abbr=on}}
| crew               = 
| passengers         = <!-- Explosive specifications -->
| filling            = 
| filling_weight     = 
| detonation         = 
| yield              = <!-- Vehicle/missile specifications -->
| armour             = 
| primary_armament   = Mk 2 or Mk 3 re-entry vehicle with 1.44 Mt [[W 49]] warhead - (Atlas D); Mk 4 re-entry vehicle with 3.75 Mt [[W-38 warhead]] - (Atlas E&F)
| secondary_armament = 
| engine             = 2 × [[Rocketdyne XLR-89]] booster rocket engines each {{cvt|150000|lbf|kN}} sharing one turbopump (Atlas A)
1 × [[Rocketdyne LR-105]] sustainer rocket engine, 2 × Rocketdyne XLR-89 booster rocket engines each {{cvt|150000|lbf|kN}} sharing one turbopump (Atlas B, C)<br><br>
1 × Rocketdyne LR-105 sustainer rocket engine, 2 × LR89 booster engines with independent turbopumps each {{cvt|165000|lbf|kN}} (Atlas D, E, F, G)
+ 2 × [[Rocketdyne LR-101]] [[Vernier thruster|vernier engines]] with {{cvt|1000|lbf|kN}} of thrust fed by LR-105 sustainer engine turbopump(s)<br>(Atlas A, B, C, D, E, F, G)
| engine_power       = 
| pw_ratio           = 
| payload_capacity   = 
| transmission       = 
| suspension         = 
| clearance          = 
| fuel_capacity      = 
| vehicle_range      = 
| speed              = 
| guidance           = 
| steering           = <!-- Missiles only -->
| wingspan           = 
| propellant         = 
| ceiling            = 
| altitude           = 
| boost              = 
| depth              = 
| accuracy           = [[circular error probable|CEP]] {{convert|4600|ft|-1|abbr=on}}
| launch_platform    = 
| transport          = <!-- For all -->
| ref                = 
}}
{{Infobox weapon
<!-- Service history -->
| service            = 1959–1964

<!-- Production history -->
| designer           =
| design_date        = 1953 (XB-65)
| unit_cost          =
| production_date    = 1959–1965
| number             = 350 (all versions)<br/>Peak deployment level of 129<br/>(30 D, 27 E, 72 F).
| variants           = Atlas A, B/C, D, E/F (ICBMs)<br/>SLV-3/3A/3C (NASA use)
}}

The '''SM-65 Atlas''' was the first operational [[intercontinental ballistic missile]] (ICBM) developed by the United States and the first member of the [[Atlas (rocket family)|Atlas rocket family]]. It was built for the [[U.S. Air Force]] by the [[Convair]] Division of [[General Dynamics]] at an assembly plant located in [[Kearny Mesa]], [[San Diego]].<ref>{{cite web|title=San Diego's Missile|date=June 28, 2007|author=Edward Hujsa|website=San Diego Reader|url=https://www.sandiegoreader.com/news/2007/jun/28/san-diego-missile/|access-date=March 17, 2023}}</ref>

The development of the Atlas begun in 1946, but over the next few years the project underwent several cancellations and re-starts. The deepening of the [[Cold War]] and intelligence showing the [[Soviet Union]] was working on an ICBM design led to it becoming a crash project in late 1952, along with the creation of several other missile projects to ensure one would enter service as soon as possible. The first test launch was carried out in June 1957, which failed. The first success of the Soviet [[R-7 Semyorka]] in August gave the program new urgency, leading to the first successful Atlas A launch in December. Of the eight flights of the A model, only three were successful, but the later models demonstrated increasing reliability and the D model was cleared for use.

Atlas C was declared operational in September 1959. Even at that time it was considered less than ideal{{citation needed|date=July 2025}} as it had to be fuelled immediately before launch and thus had very slow reaction times. The Air Force still saw its [[strategic bomber]]s as its primary force and considered Atlas as a last-ditch weapon that would ensure a counterattack in the case the Soviets attempted a sneak attack on the US bomber bases. The initial versions were stored at ground level and thus subject to attack by Soviet bombers, which greatly reduced their suitability for this role. Starting with the F models they were stored in underground silos that offered some protection from air attack. New designs, especially the [[LGM-30 Minuteman|Minuteman]], rendered Atlas obsolete and it was retired from the ICBM role by 1965.

These disadvantages had no bearing on its use for space launches, and Atlas-derived [[launch vehicle]]s served as launchers for [[NASA]] for four decades. Even before its ICBM use ended in 1965, Atlas had placed four [[Project Mercury]] astronauts in orbit and was becoming the foundation for a family of successful space launch vehicles, most notably [[Atlas Agena]] and [[Atlas Centaur]]. Mergers led to the acquisition of the Atlas Centaur line by the [[United Launch Alliance]]. Today ULA supports the larger [[Atlas V]], which combines the [[Centaur (rocket stage)|Centaur upper stage]] with a new booster. Until 1995, many retired Atlas ICBMs were refurbished and combined with upper stages to launch satellites.<ref name="centennial"/>

==History==
[[File:Theodore von Kármán 230419-F-F3405-0001 (restored).jpg|thumb|[[Theodore von Kármán]], left, is joined by Air Force and NASA officials while inspecting two of the models used in the high velocity, high altitude wind tunnels at Arnold Air Force Base. The missiles are [[AGARD-B wind tunnel model|AGARD-B]] and Atlas Series-B. (1959)]]
Atlas was the first US ICBM and one of the first large liquid-fueled rockets. As such, its early development was quite chaotic, with plans changing rapidly as flight tests revealed issues.

Atlas began in 1946 with the award of an Army Air Forces research contract to a then [[AVCO]]-owned [[Convair]] for the study of a {{convert|1500|to|5000|mi|-2|adj=on}} range missile that might at some future date carry a nuclear warhead. This [[MX-774]] project would go on to acquire the name [[Atlas (mythology)|Atlas]], a god in [[Greek mythology]], in 1951, from the [[Atlas Corporation]],  Convair’s parent since 1947.<ref name="neufeld1990">{{cite report|title=The Development of Ballistic Missiles in the United States Air Force 1945-1960|author1=Jacob Neufeld|date=1990|url=https://apps.dtic.mil/sti/pdfs/ADA439957.pdf |archive-url=https://web.archive.org/web/20230312191613/https://apps.dtic.mil/sti/pdfs/ADA439957.pdf |archive-date=2023-03-12 |url-status=live|website=dtic.mil|access-date=March 12, 2023}}</ref>{{rp|70}}

At the onset of the project, the smallest atomic warheads were all larger than the maximum theoretical payloads of the planned long range missiles, so the contract was canceled in 1947, but the Army Air Forces allowed Convair to use the remaining contract funds to launch the three almost-completed research vehicles. The three flights were only partially successful, but did show that [[balloon tank]]s and gimbaled rocket engines were valid concepts.<ref>[[RTV-A-2 Hiroc]][http://themilitarystandard.com/missile/atlas/versions.php][http://themilitarystandard.com/missile/earlydevelopment.php]</ref>

A second development contract was awarded to [[Convair]] on 23 January 1951 for what was then called MX-1593, with a relatively low priority.<ref name="neufeld1990"/>{{rp|68}} The initial design completed by Convair in 1953 was larger than the missile that eventually entered service. Estimated warhead weight was lowered from {{convert|8000|lb|-1|abbr=on}} to {{convert|3000|lb|-1|abbr=on}} based on highly favorable U.S. nuclear warhead tests in early 1954. This, in addition to the [[Soviet Union]]'s 1953 [[Joe 4]] dry fuel [[thermonuclear weapon]] test and the CIA learning that the Soviet ICBM program was making progress, led to the project being dramatically accelerated. Project Atlas was assigned the highest Air Force development priority on 14 May 1954 by General [[Thomas D. White]].<ref name="neufeld1990"/>{{rp|106}}

A major development and test contract was awarded to Convair on 14 January 1955 for a {{convert|10|ft|0|adj=on}} diameter missile to weigh about {{convert|250000|lb|-2|abbr=on}}.<ref>{{cite book |author=Dennis R. Jenkins |title=To Reach the High Frontier - Ch 2: Stage-and-a-Half, The Atlas Launch Vehicle (University Press of Kentucky, 2002) |date=11 July 2014 |pages=74–85 |publisher=University Press of Kentucky |isbn=9780813148076 |url=https://books.google.com/books?id=hKYeBgAAQBAJ&pg=PA74}}</ref> Atlas development was tightly controlled by the Air Force's Western Development Division, WDD, later part of the Air Force Ballistic Missile Division. Contracts for warhead, guidance and propulsion were handled separately by WDD. The first successful flight of a highly instrumented Atlas missile to full range occurred 28 November 1958. Atlas ICBMs were deployed operationally from 31 October 1959 to 12 April 1965.<ref>[[Mike Gruntman]], ''Blazing the Trail'', pp. 221–245, AIAA, Reston Virginia, 2004</ref>

The missile was originally designated as the XB-65 experimental bomber; in 1955 it was redesignated SM-65 ("Strategic Missile 65") and, from 1962, it became CGM-16. This letter "C" stood for "coffin" or "Container", the rocket being stored in a semi-hardened container; it was prepared for launch by being raised and fueled in the open. The Atlas-F (HGM-16) was stored vertically underground, but launched after being lifted to the surface.<ref name="armycoe"/>

By 1965, with the second-generation [[LGM-25C Titan II|Titan II]] having reached operational status, the Atlas was obsolete as a missile system and had been phased out of military use. Many of the retired Atlas D, E, and F missiles were used for space launches until the 1990s.<ref name="centennial">{{cite web|publisher=U.S. Centennial of Flight Commission|author=Roger Guillemette
|title=Atlas|url=https://www.centennialofflight.net/essay/SPACEFLIGHT/Atlas/SP10.htm|access-date=March 11, 2023}}</ref>

[[WD-40]], a [[penetrating oil]] found its first use as a corrosion-inhibiting coating for the outer skin of the Atlas missile.<ref name="aboutus">{{cite web | title = Our History | publisher = WD-40 | url = http://wd40.com/about-us/history/ | url-status = live | archive-url = https://web.archive.org/web/20140623152408/http://wd40.com/about-us/history/ | archive-date = 23 June 2014 | df = dmy-all }}</ref>

==Missile details==
{{unreferenced section|date=August 2015}}
The Atlas's complicated, unconventional design proved difficult to debug compared with rocket families such as Thor and Titan which used conventional aircraft-style structures and two stage setups. The lack of internal structure contributed to dozens of failed launches during its development. After watching [[SM-65D Atlas|Atlas Serial 7D]] [[List of Atlas launches (1957–1959)#7D|explode shortly after its nighttime launch]], Mercury astronaut [[Gus Grissom]] remarked "Are we really going to get on top of one of those things?"<ref>{{cite book |last1=Steward |first1=David |title=Seeking Success: A Memoir |date=20 April 2017 |url=https://www.academia.edu/32536245 |page=44}}</ref> The numerous failures led to Atlas being dubbed an "Inter County Ballistic Missile" by missile technicians, but by 1965 most of the problems had been worked out and it became a more reliable launch vehicle.{{citation needed|date=July 2025}} Nearly every component in the Atlas managed to fail at some point during test flights, from the engine combustion chambers to the tank pressurization system to the flight control system, but Convair engineers{{who|date=July 2025}} noted with some pride that there had never been a repeat of the same failure more than three times, and every component malfunction on an Atlas flight was figured out and resolved.{{citation needed|date=July 2025}} Some of the repeat failures were also the result of rushed launch schedules and could have been avoided.{{citation needed|date=July 2025}} The last major design hurdle to overcome was unstable engine thrust, which caused three Atlas missiles (Serial 51D and 48D in 1960 and Serial 27E in 1961) to explode on their launching stands.

===Pressure stabilized tanks===
Atlas was unusual in its use of [[balloon tank]]s for the propellants, made of very thin [[stainless steel]] with minimal or no rigid support structures, as already pioneered by the Soviet [[R-5 Pobeda|R-5]] first launched in 1953.<ref>{{Cite web |url=https://www.energia.ru/english/energia/launchers/rocket-r5.html |title=Rocket R-5 |access-date=2023-11-10 |archive-url=https://web.archive.org/web/20211023212134/https://www.energia.ru/english/energia/launchers/rocket-r5.html |archive-date=2021-10-23 |url-status=dead |publisher=S. P. Korolev RSC Energia}}</ref> Pressure in the tanks provides the structural rigidity required for flight. An Atlas rocket would collapse under its own weight if not kept pressurized, and had to have {{convert|5|psi|abbr=on}} nitrogen in the tank even when not fueled.<ref>{{cite web|author=John Pike |url=http://www.globalsecurity.org/wmd/systems/sm-65.htm |title=SM-65 Atlas – United States Nuclear Forces |publisher=Globalsecurity.org |access-date=19 July 2013}}</ref> The rocket had two small thrust chambers on the sides of the tank called [[vernier rocket]]s. These provided fine adjustment of velocity and steering after the sustainer engine shut down.

==='Stage-and-a-half'===
Atlas was informally classified as a "stage-and-a-half" rocket, with a central sustainer engine and set of two booster engines that were all started at launch, each drawing from a single set of propellant tanks.<ref name="Brugge">{{cite web |url=http://www.b14643.de/Spacerockets/Specials/Atlas_MA-drive-system/index.htm |title=Variants of the "stage and a half" drive system (MA) of the Atlas rocket |website=b14643.de |access-date=4 September 2022}}</ref><ref name="McCutcheon">{{Cite web |last1=D. McCutcheon |first1=Kimble |title=Part 5: The Atlas Missile |url=https://www.enginehistory.org/Rockets/RPE05/RPE05.shtml |url-status=live |archive-url=https://web.archive.org/web/20240828191532/https://enginehistory.org/Rockets/RPE05/RPE05.shtml |archive-date=28 August 2024 |access-date=4 September 2022 |website=U.S. Manned Rocket Propulsion Evolution }}</ref> Most [[multistage rocket]]s drop both engines and fuel tanks simultaneously before firing the next stage's engines. However, when the Atlas missile was being developed, there was doubt as to whether a rocket engine could be air-started. Therefore, the decision was made to ignite all of the Atlas' engines at launch; the booster engines would be discarded, while the sustainer continued to burn.<ref name="Brugge"/> A stage of a liquid propellant rocket normally consists of both propellant tanks and engines, so jettisoning one or more engines only is equivalent to "half a stage". At staging, the booster engines would be shut off and a series of mechanical and hydraulic mechanisms would close the plumbing lines to them. The booster section would then be released by a series of hydraulic clamps (aside from the early test model Atlas B, which used explosive bolts) and slide off the missile on two tracks. From there on, the sustainer and [[Vernier thruster|verniers]] would operate by themselves. Booster staging took place at roughly two minutes into launch, although the exact timing could vary considerably depending on the model of Atlas as well as the particular mission being flown. This "stage-and-a-half" design was made possible by the extremely light weight [[balloon tank]]s.<ref name="McCutcheon"/> The tanks made up such a small percentage of the total booster weight that the mass penalty of lifting them to orbit was less than the technical and mass penalty required to throw half of them away mid-flight. However, technology advanced quickly and not long after design work on Atlas was completed, Convair rival Martin proposed a solution to the air-starting problem. Their [[Titan I]] missile, developed as an Atlas backup, had a conventional two stage design.<ref>{{cite web|title=The Military Standard - Titan I Missile Overview |url=http://www.themilitarystandard.com/missile/titan1/overview.php|website=themilitarystandard.com|access-date=March 10, 2023}}</ref>

===Engines===
The booster engine consisted of two large thrust chambers. The Atlas A/B/C/D had a single turbopump assembly and gas generator driving both booster engines; the A/B/C had an interim engine with lower thrust while the D-series had the full-up engines delivering 303,000 pounds of thrust.<ref name="McCutcheon"/> On the Atlas E/F, each booster engine had a separate pump and gas generator. Later space launcher variants of the Atlas used the MA-5 propulsion system with twin turbopumps on each booster engine, driven by a common gas generator.<ref name="Brugge"/> The boosters were more powerful than the sustainer engine and did most of the lifting for the first two minutes of flight. In addition to pitch and yaw control, they could also perform roll control in the event of a vernier failure. The sustainer engine on all Atlas variants consisted of a single thrust chamber with its own turbopump and gas generator, which also powered two small pressure-fed vernier engines.<ref name="McCutcheon"/> The verniers provided roll control and final velocity trim. The total sea level thrust of all five thrust chambers was 360,000&nbsp;[[Pound (force)|lb<sub>''f''</sub>]] (1,600&nbsp;[[Newton (unit)|kN]]) for a standard Atlas D. Atlas E/F had 375,000 pounds of thrust. Total sea level thrust for these three-engine Atlas Es and Fs was 389,000&nbsp;lb<sub>f</sub> (1,730&nbsp;kN).<ref name="FEWarren">{{cite web|archive-url=https://web.archive.org/web/20080509071108/http://www.warrenmuseum.com/atlas.htm |archive-date=May 9, 2008|url=http://www.warrenmuseum.com/atlas.htm|title=Atlas SM-65|publisher=FE Warren Museum}}</ref> [[Launch vehicle|Launcher]] variants of the Atlas often had performance enhancements to the engines.<ref name="McCutcheon" />

===Guidance===
The Atlas missiles A through D used radio [[missile guidance|guidance]]: the missile sent information from its [[inertial guidance|inertial system]] to a ground station by radio, and received course correction information in return. The Atlas E and F had completely autonomous [[inertial guidance]] systems.

The ground based guidance computer was a key part of the missile system, until guidance computers were [[miniaturized]] enough to be installed inside the missile. [[Isaac L. Auerbach]] designed the Burroughs guidance computer for the Atlas ICBM missiles. The Burroughs guidance computer was one of the first [[transistor computer]]s. It processed [[24-bit computing|24-bit]] data using [[18-bit computing|18-bit]] instructions. A total of 17 of these ground computers were delivered. These same ground computers were later used for [[Atlas-Able]], [[Project Mercury]], and other early spacecraft.<ref>[https://afspacemuseum.org/wp-content/uploads/displays/BurroughsComputer/Burroughs_Historical_Summary.pdf "Burroughs Guidance Computer Historical Summary"] {{Webarchive|url=https://web.archive.org/web/20210506065054/https://afspacemuseum.org/wp-content/uploads/displays/BurroughsComputer/Burroughs_Historical_Summary.pdf |date=6 May 2021 }}.
2012.
p. 1, 7, 8.</ref>

===Warhead===
The warhead of the Atlas D was originally the G.E. Mk 2 "heat sink" [[re-entry vehicle]] (RV)<ref>{{cite web |title=Missile, Reentry Vehicle, Mark 2 |url=https://www.si.edu/object/missile-reentry-vehicle-mark-2%3Anasm_A19751430000 |website=si.edu}}</ref> with a [[W49]] [[thermonuclear weapon]], combined weight {{convert|3700|lb|-1|abbr=on}} and yield of 1.44 [[TNT equivalent|megatons]] (Mt). The W49 was later placed in a Mk 3 ablative RV, combined weight {{convert|2420|lb|-1|abbr=on}}. The Atlas E and F had an AVCO Mk 4 RV containing a [[W38 (nuclear warhead)|W38]] [[thermonuclear weapon|thermonuclear warhead]] with a yield of 3.75&nbsp;Mt<ref>{{cite web |title=Missile, Reentry Vehicle, Mark 4 |url=https://airandspace.si.edu/collection-objects/missile-reentry-vehicle-mark-4/nasm_A19660029000 |website=airandspace.si.edu}}</ref> which was [[fuze]]d for either air burst or contact burst. The Mk 4 RV also deployed [[penetration aid]]s in the form of [[mylar]] balloons which replicated the radar signature of the Mk 4 RV. The Mk 4 plus W-38 had a combined weight of {{convert|4050|lb|-1|abbr=on}}. All of the warheads deployed in the Atlas were over 100 times more powerful than the [[Atomic bombings of Hiroshima and Nagasaki|bomb dropped over Nagasaki]] in 1945.<ref>{{cite web|title=Fairchild had a missile squadron… Who knew?|date=June 4, 2014|author=Jim O'Connell |url=https://www.fairchild.af.mil/News/Commentaries/Display/Article/496434/fairchild-had-a-missile-squadron-who-knew/
|website=U.S. Air Force|access-date=March 11, 2023}}</ref>

===Comparison with R-7===
The [[R-7 Semyorka]] was the first Soviet ICBM and similarly started all engines before launch to avoid igniting a large liquid fuel engine at high altitudes. However, the R-7 had a central sustainer section, with four boosters attached to its sides. The large side boosters required use of an expensive launch pad and prevented launching the rocket from a silo. Like the Atlas, the use of [[cryogenic]] [[liquid oxygen]] meant that the missile could not be kept in the state of flight readiness indefinitely, was largely useless as a strategic weapon, and was similarly developed into a space launch vehicle, initially delivering [[Sputnik 1|Sputnik]] and [[Vostok 1|Vostok]] into orbit. The [[Soyuz (rocket family)|Soyuz rocket]] is descended from the R-7 and remains in use today.<ref>{{Cite web|date=2020-04-27|script-title=ru:Коммерческий полет "Союза" на МКС планируется в 2022-2023 годах|trans-title=Soyuz commercial flight to the ISS planned for 2022-2023|url=https://ria.ru/20200427/1570605489.html|access-date=2020-06-26|website=РИА Новости|language=ru}}</ref>

==Missile versions==
===SM-65A Atlas===
{{main | SM-65A Atlas }}
[[File:Atlas missile test launch.jpg|thumb|150x150px|Atlas, test number 449, Air Force Missile Test Center.]]
The [[Convair]] '''X-11'''/'''SM-65A Atlas'''/'''Atlas A''' was the first full-scale prototype of the Atlas missile, first flying on 11 June 1957.<ref name="EA">{{cite web |url=http://www.astronautix.com/lvs/atlasa.htm |title=Encyclopedia Astronautica – Atlas A |publisher=Astronautix.com |access-date=19 July 2013 |url-status=dead |archive-url=https://web.archive.org/web/20130522064526/http://www.astronautix.com/lvs/atlasa.htm |archive-date=22 May 2013 |df=dmy-all }}</ref> It was a test model designed to verify the structure and propulsion system, and had no sustainer engine or separable stages. The first three Atlas A launches used an early Rocketdyne engine design with conical thrust chambers and only 135,000 pounds of thrust. By the fourth Atlas test, they were replaced by an improved engine design that had bell-shaped thrust chambers and 150,000 pounds of thrust.

There were eight Atlas A test flights, conducted in 1957–58, of which four were successful. All were launched from [[Cape Canaveral Air Force Station]], at either [[Cape Canaveral Air Force Station Launch Complex 12|Launch Complex 12]] or [[Cape Canaveral Air Force Station Launch Complex 14|Launch Complex 14]].<ref name="EA" />

===SM-65B Atlas===
[[File:Atlas-B ICBM.jpg|thumbnail|Launch of an Atlas B ICBM.|150x150px]]
{{main | SM-65B Atlas }}
The '''Convair X-12'''/'''SM-65B''' was the second prototype version, introducing the [[stage and a half]] system that was a hallmark of the Atlas rocket program. This version was the first American rocket to achieve a flight distance that could be considered intercontinental when it flew {{convert|6325|mi|-1}}.<ref>{{cite web
 | title = Cape Canaveral Launch Chronology
 | url = https://www.spaceline.org/statistics/Cape_Canaveral_Launch_Chronology.html
 | website = Spaceline.org
 | access-date = Feb 27, 2021}}</ref>

The Atlas B was first flown on 19 July 1958. Of ten total flights, nine were [[sub-orbital]] test flights of the Atlas as an [[Intercontinental Ballistic Missile]], with five successful missions and four failures; the other flight placed the [[SCORE (satellite)|SCORE satellite]] into orbit. All launches were conducted from [[Cape Canaveral Air Force Station]], at Launch Complexes [[Cape Canaveral Air Force Station Launch Complex 11|11]], [[Cape Canaveral Air Force Station Launch Complex 13|13]] and [[Cape Canaveral Air Force Station Launch Complex 14|14]].<ref name="EA" />

=== SM-65C Atlas ===
{{main | SM-65C Atlas }}
[[File:Atlas C.jpg|thumb|150x150px|Atlas C missile sitting on its launch pad.]]
The '''SM-65C Atlas''', or '''Atlas C''' was the third prototype Atlas version, a more refined model with improved, lighter-weight components. a bigger LOX tank, and a smaller fuel tank. First flown on 24 December 1958, it was the final development version. It was originally planned to be used as the first stage of the [[Atlas-Able]] rocket, but following an explosion during a static test on 24 September 1959, this was abandoned in favor of the Atlas D.<ref>{{cite web|url=https://www.thespacereview.com/article/1741/1|title=The Pioneer lunar orbiters: a forgotten failure|author=Andrew J. LePage|date=December 13, 2010|website=thespacerview.com|access-date=March 12, 2023}}</ref> Six flights were made, all sub-orbital ballistic test flights of the Atlas, with three tests succeeding, and three failing.<ref>{{cite web|title=Atlas C|url=http://www.astronautix.com/a/atlasc.html|website=astronautix.com|access-date=March 11, 2023}}</ref> All launches were conducted from Cape Canaveral Air Force Station, at Launch Complex 12.<ref>{{cite web|title=Launch Complex 12|url=http://mail.afspacemuseum.org/ccafs/CX12/|publisher=Air Force Space and Missile Museum|access-date=March 11, 2023}}</ref>

=== SM-65D Atlas ===
{{main|SM-65D Atlas}}
[[File:564th Strategic Missile Squadron Convair SM-65D Atlas missile 58-2205.jpg|thumb|150x150px|SM-65D Atlas missile 58-220, F. E. Warren AFB.]]
The '''SM-65D Atlas''', or '''Atlas D''', was the first operational version of the Atlas missile and the basis for all Atlas space launchers, debuting in 1959.<ref>Andreas Parsch, "Atlas D, Historical Essay", Encyclopedia Astronautica, 2003</ref> Atlas D weighed {{convert|255950|lb|-1|abbr=on}} (without payload) and had an empty weight of only {{convert|11894|lb|abbr=on}}; the other 95.35% was propellant.  Dropping the {{convert|6720|lb|0|abbr=on}} booster engine and fairing reduced the dry weight to {{convert|5174|lb|abbr=on}}, a mere 2.02% of the initial gross weight of the vehicle (still excluding payload). This very low dry weight gave Atlas D a range of up to {{convert|9000|mi|-2}}, or to orbit payloads without requiring an upper stage.<ref>M. D. Black, ''The Evolution of ROCKET TECHNOLOGY'', p. 54, Native Planter, SLC, 2012, payloadz.com under ''ebook/History''</ref> It first flew on 14 April 1959.

To provide the United States with an interim or emergency ICBM capability, in September 1959 the Air Force deployed three SM-65D Atlas missiles on open launch pads at [[Vandenberg AFB]], California, under the operational control of the [[576th Strategic Missile Squadron]], [[704th Strategic Missile Wing]]. Completely exposed to the elements, the three missiles were serviced by a gantry crane. One missile was on operational alert at all times.<ref>{{cite web|title=The ICBM turns 60|date=October 31, 2019|author=Troy A. Hallsell|url=https://www.afgsc.af.mil/News/Commentaries/Display/Article/2006393/the-icbm-turns-60/|website=U.S. Air Force|access-date=March 11, 2023}}</ref> They remained on alert until 1 May 1964.<ref name="nrdcstrat">{{cite report|title=US-USSR/Russian Strategic Offensive Nuclear Forces|date=January 1997|author1=Robert S. Norris|author2=Thomas B. Cochran|url=https://nuke.fas.org/norris/nuc_01009701a_181.pdf |archive-url=https://web.archive.org/web/20211223134358/https://nuke.fas.org/norris/nuc_01009701a_181.pdf |archive-date=2021-12-23 |url-status=live|publisher=National Resources Defense Council, Inc.|page=16|access-date=March 11, 2023}}</ref>

=== SM-65E Atlas ===
{{main | SM-65E Atlas }}
[[File:Atlas-5E rocket-02.jpg|thumb|150x150px|Atlas-E missile (s/n 5E), Cape Canaveral LC-11.]]
The '''SM-65E Atlas''', or '''Atlas-E''', was the first 3-engine operational variant of the Atlas missile, the third engine resulting from splitting the two booster thrust chambers into separate engines with independent sets of turbopumps. It first flew on 11 October 1960, and was deployed as an operational [[ICBM]] from September 1961 until March 1965.<ref>James N. Gibson, ''Nuclear Weapons of the United States, An Illustrated History'', pp. 11–14, Schiffer Publishing Ltd., Atglen, PA, 1996</ref>

A major enhancement in the Atlas E was the new all-inertial system that obviated the need for ground control facilities. Since the missiles were no longer tied to a central guidance control facility, the launchers could be dispersed more widely in what was called a 1&nbsp;×&nbsp;9 configuration, with one missile silo located at one launch site each for the nine missiles assigned to the squadron.<ref name="FEWarren"/>

Atlas-E launches were conducted from Cape Canaveral Air Force Station, at Launch Complexes 11 and 13, and Vandenberg Air Force Base at [[Vandenberg AFB Operational Silo Test Facility]], Vandenberg AFB Launch Complex 576 and [[Vandenberg AFB Space Launch Complex 3]].<ref name="EA" />

=== SM-65F Atlas ===
{{main | SM-65F Atlas }}
[[File:Convair SM-65F Atlas 532 550 SMS Site 02 Abilene KS.jpg|thumb|150x150px|Convair SM-65F Atlas 532 550 SMS Site 02 Abilene KS.]]
The '''SM-65F Atlas''', or '''Atlas-F''', was the final operational variant of the Atlas missile. It first flew on 8 August 1961, and was deployed as an operational ICBM between September 1962 and April 1965.

The Atlas F was essentially a quick-firing version of the Atlas E, modified to be stored in a vertical position inside underground concrete and steel silos. It was nearly identical to the E version except for interfaces associated with their different basing modes (underground silo for F) and the fuel management system.<ref>{{cite magazine |title=Atlas ICBM Geared to Total Deployment |magazine=Aviation Week and Space Technology, 25 September 1961 |pages=143–149 |url=https://archive.org/details/sim_aviation-week-space-technology_1961-09-25_75_13/page/142/mode/2up}}</ref> When stored, the missile sat atop an elevator. If placed on alert, it was fueled with [[RP-1]] (kerosene) liquid fuel, which could be stored inside the missile for extended periods. If a decision was made to launch, it was fueled with [[liquid oxygen]]. Once the liquid oxygen fueling was complete, the elevator raised the missile to the surface for launching.<ref>{{cite web|title=How the Air Force Got the ICBM|author=John T. Correll|date=July 1, 2005|url=https://www.airandspaceforces.com/article/0705icbm/|publisher=Air and Space Forces Magazine|access-date=March 11, 2023}}</ref>

This method of storage allowed the Atlas F to be launched in about ten minutes,<ref name="csisatlas">{{cite web|title=Missile Defense Project, "SM-65 Atlas|publisher=Missile Threat, Center for Strategic and International Studies|date=August 2, 2021|access-date=March 11, 2023|url=https://missilethreat.csis.org/missile/atlas/}}</ref> a saving of about five minutes over the Atlas D and Atlas E, both of which were stored horizontally and had to be raised to a vertical position before being fueled.<ref name="csisatlas"/>

Atlas-F launches were conducted from Cape Canaveral Air Force Station, at Launch Complexes 11 and 13, and Vandenberg Air Force Base at [[Vandenberg AFB Operational Silo Test Facility|OSTF-2]], Vandenberg AFB Launch Complex 576 and Vandenberg AFB Space Launch Complex 3.<ref name="EA" />

==Operational deployment==
[[File:SM-65 Atlas Missile Sites.png|thumb|500px|SM-65 Atlas deployment sites: &nbsp;SM-65D (Red), SM-65E (Purple), SM-65F (Black)]]
[[Strategic Air Command]] deployed 13 operational Atlas ICBM squadrons between 1959 and 1962. Each of the three missile variants, the Atlas D, E, and F series, were deployed and based in progressively more secure launchers.<ref name="coldwarlegacy"/>{{rp|216}}

===Service history===
The number of Atlas intercontinental ballistic missiles in service, at the end of each year:<ref name="nrdcstrat"/>{{rp|Table 3}}

{| class=wikitable style="text-align:center"
|-
! Date
! CGM-16D<br/> (Atlas D)
! CGM-16E<br/> (Atlas E)
! HGM-16F<br/> (Atlas F)
|-
| 1959||  6|| 0|| 0
|-
| 1960|| 12|| 0|| 0
|-
| 1961|| 30||27|| 0
|-
| 1962|| 30||27|| 72
|-
| 1963|| 20||27|| 72
|-
| 1964||  0|| 0|| 72
|}

===Atlas-D deployment===
[[Image:Atlas-icbm-erection-large.jpg|thumb|Atlas-D ICBM launching from semi-hardened "coffin" bunker at Vandenberg AFB, California.]]
In September 1959 the first operational Atlas ICBM squadron went on operational alert at [[F.E. Warren AFB]],<ref name="AtlD">{{cite web |url=http://www.siloworld.net/ICBM/ATLAS/ATD/location2.htm |title=Atlas D Locations |website=siloworld.net |archive-url=https://web.archive.org/web/20220713171215/http://www.siloworld.net/ICBM/ATLAS/ATD/location2.htm |archive-date=13 July 2022}}</ref> Wyoming equipped with six [[SM-65D Atlas]] missiles based in above-ground launchers.  Three additional Atlas D squadrons, two near F.E. Warren AFB, Wyoming, and one at [[Offutt AFB]], Nebraska,<ref name="AtlD"/> were based in above-ground launchers that provided blast protection against over-pressures of only {{convert|5|psi}}.
These units were:
* [[389th Strategic Missile Wing]]
: [[Francis E. Warren AFB]], [[Wyoming]] (2 September 1960 – 1 July 1964)
: [[564th Strategic Missile Squadron]] (6 missiles)
: [[565th Strategic Missile Squadron]] (9 missiles)

* [[385th Strategic Aerospace Wing|385th Bombardment (later Strategic Aerospace) Wing]]
: [[Offutt AFB]], [[Nebraska]] (30 March 1961 – 1 October 1964)
: [[549th Strategic Missile Squadron]] (9 missiles)

The first site at Warren for the 564th SMS consisted of six launchers grouped together, controlled by two launch operations buildings, and clustered around a central guidance control facility. This was called the 3&nbsp;×&nbsp;2 configuration: two launch complexes of three missiles each constituted a squadron.<ref name="coldwarlegacy">{{cite report|title=To Defend and Deter: The Legacy of the United States Cold War Missile Program|author1=John C. Lonnquest |author2=David F. Winkler|date=November 1996
|url=https://apps.dtic.mil/sti/pdfs/ADA337549.pdf |archive-url=https://web.archive.org/web/20201020041232/https://apps.dtic.mil/sti/pdfs/ADA337549.pdf |archive-date=2020-10-20 |url-status=live|website=dtic.mil|publisher=Department of Defense Legacy Resource Management Program Cold War Project|access-date=March 12, 2023}}</ref>{{rp|218}}

At the second Warren site for the 565th SMS and at Offutt AFB, Nebraska, for the 549th SMS, the missiles were based in a 3 x 3 configuration: three launchers and one combined guidance control/launch facility constituted a launch complex, and three complexes comprised a squadron. At these later sites the combined guidance and control facility measured {{convert|107|by|121|ft|0|abbr=on}} with a partial basement.  A dispersal technique of spreading the launch complexes were {{convert|20|to|30|mi|-1}} apart was also employed to reduce the risk that one powerful nuclear warhead could destroy multiple launch sites.<ref name="coldwarlegacy"/>

===Atlas-E deployment===
The SM-65E Atlas were based in horizontal "semi-hard" or "coffin" facilities that protected the missile against over-pressures up to {{convert|25|psi|abbr=on}}. In this arrangement the missile, its support facilities, and the launch operations building were housed in reinforced concrete structures that were buried underground; only the roofs protruded above ground level. These units were:<ref name="AtlE">{{cite web |url=http://www.siloworld.net/ICBM/ATLAS/ATE/location3.htm |title=Atlas E Locations |website=siloworld.net |archive-url=https://web.archive.org/web/20220714124029/http://www.siloworld.net/ICBM/ATLAS/ATE/location3.htm |archive-date=14 July 2022 |url-status=live}}</ref>
* [[92d Bombardment Wing|92nd Bombardment (later Strategic Aerospace) Wing]]
: [[Fairchild Air Force Base]], [[Washington (state)|Washington]] (28 September 1961 – 17 February 1965)
: [[567th Strategic Missile Squadron]], (9 missiles)

* [[21st Strategic Aerospace Division]]
: [[Forbes AFB]], [[Kansas]] (10 October 1961 – 4 January 1965)
: [[548th Strategic Missile Squadron]], (9 missiles)

* [[389th Strategic Missile Wing]]
: [[Francis E. Warren AFB]], [[Wyoming]] (20 November 1961 – 4 January 1965)
: [[566th Strategic Missile Squadron]] (9 missiles)

===Atlas-F deployment===
The six [[SM-65F Atlas]] squadrons were the first ICBMs to be stored vertically in underground silos. Built of heavily reinforced concrete, the huge silos were designed to protect the missiles from over-pressures of up to {{convert|100|psi|abbr=on}}.<ref name="armycoe">{{cite web|title=Historical Vignette 032 - The Corps Built the Launch Sites for Atlas ICBM|date=August 2001 |url=https://www.usace.army.mil/About/History/Historical-Vignettes/Military-Construction-Combat/032-Atlas-ICBM/|publisher=U.S. Army Corps of Engineers|access-date=March 11, 2023}}</ref> These units were:<ref name="AtlF">{{cite web |url=http://www.siloworld.net/ICBM/ATLAS/ATF/LOCATION.HTM |title=Atlas F Locations |website=siloworld.net |archive-url=https://web.archive.org/web/20201112045023/http://www.siloworld.net/ICBM/ATLAS/ATF/LOCATION.HTM |archive-date=12 November 2020 |url-status=live}}</ref>
{{Col-begin}}
{{Col-break|width=50%}}
* [[310th Strategic Aerospace Wing|310th Bombardment (later Strategic Aerospace) Wing]]
: [[Schilling AFB]], [[Kansas]] (9 September 1962 – 1 February 1965)
: [[550th Strategic Missile Squadron]] (12 missiles)

* [[98th Strategic Aerospace Wing]]
: [[Lincoln AFB]], [[Nebraska]] (15 September 1962 – 10 March 1965)
: [[551st Strategic Missile Squadron]] (12 missiles)

* [[11th Wing|11th Bombardment (later Strategic Aerospace) Wing]]
: [[Altus AFB]], [[Oklahoma]] (9 October 1962 – 30 December 1964)
: [[577th Strategic Missile Squadron]] (12 missiles)

{{Col-break|width=50%}}
* [[96th Air Base Wing|96th Bombardment (later Strategic Aerospace) Wing]]
: [[Dyess AFB]], [[Texas]] (15 November 1962 – 1 December 1964)
: [[578th Strategic Missile Squadron]] (12 missiles)

* [[6th Air Mobility Wing|6th Bombardment (later Strategic Aerospace) Wing]]
: [[Walker AFB]], [[New Mexico]] (30 November 1962 – 5 January 1965)
: [[579th Strategic Missile Squadron]] (12 missiles)

* [[820th Strategic Aerospace Division|820th Air (later Strategic Aerospace) Division]]
: [[Plattsburgh AFB]], [[New York (state)|New York]] (20 December 1962 – 12 March 1965)
: [[556th Strategic Missile Squadron]] (12 missiles)
{{col-end}}
The Atlas F's employment was dangerous due to the flammability of the stored liquid rocket fuels.  Four sites and their missiles were destroyed during propellant loading exercises (known as PLXs) when liquid oxygen leaked and fires ensued.  On 1 June 1963 Roswell's site 579-1 was destroyed by explosion and fire.  On 13 February 1964 Roswell's site 579-5 was destroyed, and a month later on 9 March 1964 site 579-2 was also destroyed by explosion and fire.  Finally, on 14 May 1964 an Altus AFB site, 577-6 in Frederick, Oklahoma, was also destroyed by explosion and fire during a PLX.  Fortunately the crews all survived.  None of the damaged sites were repaired or returned to service.

===Retirement as an ICBM===
[[File:Ten Years To Remember 1964.webm|thumb|''"The Martin Company: Ten Years To Remember"'' (1964). Official [[USAF]] ICBM development promotional film reel.]]
After the [[Solid-fuel rocket|solid-fuel]] [[LGM-30 Minuteman]] had become operational in early 1963, the Atlas became rapidly obsolete.<ref>{{cite web|title=Air Force history of ICBM development, safeguarding America
|date=March 5, 2012|author=Reggie Manning|url=https://www.afgsc.af.mil/News/Features/Display/Article/455710/air-force-history-of-icbm-development-safeguarding-america/|website=U.S. Air Force|access-date=March 11, 2023}}</ref> By October 1964, all Atlas D missiles had been phased out, followed by the Atlas E/F in April 1965. About 350 Atlas ICBMs of all versions were built, with a peak deployment level of 129 (30 D, 27 E, 72 F). Despite its relatively short life span, Atlas served as the proving ground for many new missile technologies. Perhaps more importantly, its development spawned the organization, policies, and procedures that paved the way for all of the later ICBM programs.<ref>{{cite web |author=Parsch, Andreas |title=Directory of U.S. Military Rockets and Missiles - Convair B-65/SM-65/CGM-16/HGM-16 Atlas |url=https://www.designation-systems.net/dusrm/m-16.html |archive-url=https://web.archive.org/web/20021003044253/http://www.designation-systems.net/dusrm/m-16.html |archive-date=3 October 2002 |url-status=live}}</ref>

After its retirement from operational ICBM service in 1965, the ICBMs were refurbished and used for close to forty years as space launch vehicle boosters.<ref name="csisatlas"/>

==Atlas-A to -C launch history==

=== SM-65A (Atlas A) variant launch history===
[[File:USAF ICBM and NASA Launch Vehicle Flight Test Successes and Failures (highlighted).png|360px|thumb|right|1965 graph of Atlas launches, cumulative by month with failures highlighted (pink) along with USAF Titan II and NASA use of ICBM boosters for Projects Mercury and Gemini (blue). Apollo–Saturn history and projections shown as well.]]
Eight flights of Atlas A occurred during the history of this variant.<ref>{{cite web|url=http://www.astronautix.com/a/atlasa.html|title=Atlas A|website=astronautix.com|access-date=March 13, 2023}}</ref>
{| class=wikitable style="text-align:center"
|-
! (SM-65A)<br />Date
! Time<br />([[GMT]])
! Pad
! Serial
! [[Apogee]]
! Outcome
|-
| 1957-06-11
| 19:37
| LC-14
| 4A
| {{convert|2|km|abbr=on}}
| Failure
|-
| 1957-09-25
| 19:57
| LC-14
| 6A
| {{convert|3|km|abbr=on}}
| Failure
|-
| 1957-12-17
| 17:39
| LC-14
| 12A
| {{convert|120|km|abbr=on}}
| Success
|-
| 1958-01-10
| 15:48
| LC-12
| 10A
| {{convert|120|km|abbr=on}}
| Success
|-
| 1958-02-07
| 19:37
| LC-14
| 13A
| {{convert|120|km|abbr=on}}
| Failure
|-
| 1958-02-20
| 17:46
| LC-12
| 11A
| {{convert|90|km|abbr=on}}
| Failure
|-
| 1958-04-05
| 17:01
| LC-14
| 15A
| {{convert|100|km|abbr=on}}
| Success
|-
| 1958-06-03
| 21:28
| LC-12
| 16A
| {{convert|120|km|abbr=on}}
| Success
|}

=== SM-65B (Atlas B) variant launch history===
Ten flights of Atlas B occurred during the history of this variant.<ref>{{cite web|url=http://www.astronautix.com/a/atlasb.html|title=Atlas B|website=astronautix.com|access-date=March 13, 2023}}</ref>
{| class=wikitable style="text-align:center"
|-
! (SM-65B)<br />Date
! Time<br />([[GMT]])
! Pad
! Serial
! [[Apogee]]
! Outcome
! Remarks
|-
| {{nowrap|1958-07-19}}
| {{nowrap|17:36}}
| {{nowrap|LC-11}}
| 3B
| {{convert|10|km|abbr=on}}
| Failure
|
|-
| 1958-08-02
| 22:16
| LC-13
| 4B
| {{convert|900|km|abbr=on}}
| Success
|
|-
| 1958-08-29
| 04:30
| LC-11
| 5B
| {{convert|900|km|abbr=on}}
| Success
|
|-
| 1958-09-14
| 05:24
| LC-14
| 8B
| {{convert|900|km|abbr=on}}
| Success
|
|-
| 1958-09-18
| 21:27
| LC-13
| 6B
| {{convert|100|km|abbr=on}}
| Failure
|
|-
| 1958-11-18
| 04:00
| LC-11
| 9B
| {{convert|800|km|abbr=on}}
| Failure
|
|-
| 1958-11-29
| 02:27
| LC-14
| 12B
| {{convert|900|km|abbr=on}}
| Success
| First full-range test flight
|-
| 1958-12-18
| 22:02
| LC-11
| 10B
| N/A
| Success
| Placed [[Project SCORE|SCORE]] satellite<br />into {{convert|185|km|abbr=on}} x<br />{{convert|1484|km|abbr=on}} x 32.3° orbit
|-
| 1959-01-16
| 04:00
| LC-14
| 13B
| {{convert|100|km|abbr=on}}
| Failure
|
|-
| 1959-02-04
| 08:01
| LC-11
| 11B
| {{convert|900|km|abbr=on}}
| Success
|
|}

=== SM-65C (Atlas C) variant launch history===
Six flights of Atlas C occurred during the history of this variant.<ref>{{cite web|url=http://www.astronautix.com/a/atlasc.html|title=Atlas C|website=astronautix.com|access-date=March 13, 2023}}</ref>

{| class=wikitable style="text-align:center"
|-
! (SM-65C)<br />Date
! Time<br />([[GMT]])
! Pad
! Serial
! [[Apogee]]
! Outcome
|-
| {{nowrap|1958-12-24}}
| {{nowrap|04:45}}
| LC-12
| 3C
| {{convert|900|km|abbr=on}}
| Success
|-
| {{nowrap|1959-01-27}}
| {{nowrap|23:34}}
| LC-12
| 4C
| {{convert|900|km|abbr=on}}
| Failure
|-
| {{nowrap|1959-02-20}}
| {{nowrap|05:38}}
| LC-12
| 5C
| {{convert|100|km|abbr=on}}
| Failure
|-
| {{nowrap|1959-03-19}}
| {{nowrap|00:59}}
| LC-12
| 7C
| {{convert|200|km|abbr=on}}
| Failure
|-
| {{nowrap|1959-07-21}}
| {{nowrap|05:22}}
| LC-12
| 8C
| {{convert|900|km|abbr=on}}
| Success
|-
| {{nowrap|1959-08-24}}
| {{nowrap|15:53}}
| LC-12
| 11C
| {{convert|900|km|abbr=on}}
| Success
|}

==Survivors==
* HGM-16F Atlas is on display at the [[National Museum of the United States Air Force]] in [[Dayton, Ohio]]. For years the missile was displayed outside the museum. In 1998 it was removed from display. It was restored by the museum's restoration staff and returned to display in the museum's new Missile Silo Gallery in 2007. The stage is currently in storage at the museum.<ref>{{cite news|title=7 artifacts you can't see at the Air Force Museum: A peek inside the storage building
|author1=Ty Greenlees|date=June 12, 2020|url=https://www.daytondailynews.com/news/you-can-see-these-artifacts-the-air-force-museum-here-behind-the-scenes-look/DF45v2MESL2ZBvMKKBk26H/|work=Dayton Daily News|access-date=March 12, 2023}}</ref> The white nose cone atop the museum's Atlas is an AVCO IV re-entry vehicle built to contain a nuclear warhead. This nose cone actually stood alert in defense of the United States, as it was initially installed on an Atlas on 2 October 1962 at a Denton Valley launch site near [[Clyde, Texas]].<ref>{{cite web|title=United States Air Force Museum|work=Air Force Museum|date=1987
|url=https://books.google.com/books?id=ITzcFZxJQFoC|access-date=March 12, 2023|page=118}}</ref>
* Atlas 8A is displayed in front of the [[Strategic Air Command & Aerospace Museum]] in Ashland, Nebraska; reconfigured as an Atlas D.<ref name="atlasdisplays">{{cite web|title=Topic Atlas Displays|url=https://forum.nasaspaceflight.com/index.php?topic=16540.20|website=nasaspaceflight.com|access-date=March 10, 2023}}</ref>
* Atlas 2E is on display in front of the [[San Diego Air & Space Museum]] at [[Gillespie Field]], El Cajon, California.<ref>{{cite web|title=Air and Space Annex, Gillespie Field|url=https://m.sites.google.com/a/sdceonline.com/rsd/our-weekly-trips/air-and-space-annex|work=Rediscovering San Diego|access-date=March 12, 2023}}</ref>
* Atlas 2D mounted with a Mercury capsule is on display in the Rocket Garden at the [[Kennedy Space Center Visitor Complex]], Merritt Island, Florida.<ref>{{cite web|title=Convair Atlas 2D - NASA|url=https://www.airliners.net/photo/NASA/Convair-Atlas-2D/2193355/L?qsp=eJyrVkrOzytJrSgJqSxIVbJSSsxJKs1V0lEqSCxKzC1WsqqGiHimKFkZGltamtbWAgDBNBDg|website=airliners.net|access-date=March 12, 2023}}</ref>
* Atlas 10F is on display at the [[U.S. Space & Rocket Center]] in Huntsville, Alabama.<ref>{{cite web|title=Historic Spacecraft Atlas Rockets Overview#Atlas-F ICBM|url=https://historicspacecraft.com/Rockets_Atlas.html|website=historicspacecraft.com
|access-date=March 11, 2023}}</ref>

Former survivor:
* Atlas 5A (56–6742) was formerly on display on the lawn in front of the [[Canada Science and Technology Museum]] in [[Ottawa|Ottawa, Ontario, Canada]], but was removed in February 2015 and dismantled.<ref>{{cite web|url=https://www.ctvnews.ca/ottawa/article/atlas-rocket-at-science-and-technology-museum-dismantled/|title=Atlas Rocket at Science and Technology Museum dismantled|date=25 February 2015|website=ctvnews.ca|access-date=2 May 2018|url-status=live|archive-url=https://web.archive.org/web/20150810194333/http://ottawa.ctvnews.ca/atlas-rocket-at-science-and-technology-museum-dismantled-1.2253096|archive-date=10 August 2015|df=dmy-all}}</ref>
<!--(5A was on display throughout the 1960s at the former location of the Air Force Museum, at Wright-Patterson AFB Building 89 near Xenia Drive in Fairborn, Ohio. Formerly a static-test article, it is the only surviving Atlas in the original A-series configuration, before the boat-tail modifications that solved thermal issues which caused the early termination of the first two Atlas test flights, 4A and 6A.)--><gallery>
File:SAC Museum exterior 2.JPG|Atlas 8A, [[Strategic Air Command & Aerospace Museum]] (reconfigured as Atlas D)
File:Atlas missile 2-E at San Diego Air & Space Museum annex.jpg|Atlas 2E, [[San Diego Air & Space Museum]], [[Gillespie Field]]
File:KSC-20161209-PH KLS01-0004.jpg|Atlas 2D, [[Kennedy Space Center Visitor Complex]] (mounted with a Mercury capsule)
File:Rocket Alley.jpg|Atlas 10F, [[U.S. Space & Rocket Center]] (left, on transporter)
File:CMST-Convair Atlas Rocket.jpg|Atlas 5A (56–6742), [[Canada Science and Technology Museum]]
</gallery>

==Gallery==
{{multiple image
|align= center
|width=
|image1= Convair XSM-65A launch.jpg
|width1= 112
|caption1= Convair XSM-65A being launched
|image2= Convair XSM-65B launch.jpg
|width2= 157
|caption2= Convair XSM-65B being launched
|image3= Atlas C.jpg
|width3= 113
|caption3= Atlas C missile sitting on its launch pad, 1957/58
|image4= Atlas-E.jpg
|width4= 130
|caption4= Launch of an SM-65E Atlas
|image5= Atlas-F.jpg
|width5= 125
|caption5= Launch of an SM-65F Atlas
}}

===Video resources===
<gallery class="center" widths="220">
File:Atlas The ICBM (1957).webm|"''Atlas: The ICBM"'' (1957) De-classified USAF information film reel.
File:On Target, The Atlas ICBM 1958.webm|''"On Target, The Atlas ICBM"'' (1958).
File:Atlas Ready 1960.webm|''"Atlas: Ready"'' (1960).
</gallery>

==See also==
{{aircontent
|comparable aircraft header=Comparable missiles
|similar aircraft=
* [[R-7 (rocket family)|Soviet R-7 (later Soyuz) family]]
* [[HGM-25A Titan I|SM-68 Titan I]]
* [[LGM-25C Titan II|SM-68 Titan II]]
|see also=

*[[Strategic Air Command]]
|lists=
* [[List of military aircraft of the United States]]
* [[List of missiles]]

}}

==References==
{{Air Force Historical Research Agency}}
{{Reflist}}
50.  https://www.nytimes.com/1964/03/10/archives/atlas-blows-up-in-its-site-at-new-mexico-desert-base.html

==Further reading==
* Gunston, Bill (1979). ''Illustrated Encyclopedia of the World's Rockets & Missiles.'' London: Salamander Books. {{ISBN|0-517-26870-1}}.
* Walker, Chuck, & Powell, Joel (2005). ''Atlas The Ultimate Weapon''. Burlington, Ontario, Canada: Apogee Books. {{ISBN|1-894959-18-3}}.
* {{cite book|editor=Maurer, Maurer|title=Combat Squadrons of the Air Force, World War II|orig-year=1969|url= http://media.defense.gov/2010/Dec/02/2001329899/-1/-1/0/AFD-101202-002.pdf |archive-url=https://web.archive.org/web/20161220180455/http://media.defense.gov/2010/Dec/02/2001329899/-1/-1/0/AFD-101202-002.pdf |archive-date=2016-12-20 |url-status=dead |edition= reprint|year=1982|publisher=Office of Air Force History|location=Washington, DC|isbn=0-405-12194-6|oclc=72556|lccn=70605402}}

==External links==
{{Commons|Atlas (rocket)}}
* {{Internet Archive film clip|id=1958-12-22_Atlas_In_Orbit|description="Atlas in Orbit. Radios Ike's Message of Peace To World, 1958/12/22 (1958)"}}
* [http://www.rootsweb.com/~gsfa/heroes.html#Karel%20Jan%20Bossart Karel Jan Bossart, Ir.]
* [http://www.designation-systems.net/dusrm/m-16.html Atlas launch vehicle profile]
* [https://web.archive.org/web/20040820194147/http://www.astronautix.com/lvs/atlasd.htm Atlas D] from Encyclopedia Astronautica
* [http://www.techbastard.com/missile/atlas/index.php Atlas ICBM Information/History]
* [https://www.youtube.com/watch?v=Dg9PdW9yb3c Video of an early Atlas launch in 1960]
* [https://www.youtube.com/watch?v=KTOpjhL1430 1958 Video of "Atlas in Orbit" Newsreel]
* [http://www.maniacworld.com/Atlas-ICBM-Launched.htm Atlas ICBM Launch on 5/23/1960] Video
* [http://www.atlasbases.homestead.com/ 556th Missile Sites]
* [https://www.youtube.com/watch?v=fTK5RwsPyzE Atlas D Booster Package Jettison (BPJ) Test Footage]

{{Atlas rockets}}
{{US missiles}}
{{USAF missiles}}
{{USAF bomber aircraft}}
{{Lockheed Martin}}
{{Project Mercury}}
{{USAF system codes}}
{{Authority control}}

{{DEFAULTSORT:Sm-65 Atlas}}
[[Category:1958 in spaceflight]]
[[Category:1960 in spaceflight]]
[[Category:1961 in spaceflight]]
[[Category:1963 in spaceflight]]
[[Category:1965 in spaceflight]]
[[Category:1966 in spaceflight]]
[[Category:1971 in spaceflight]]
[[Category:1972 in spaceflight]]
[[Category:1973 in spaceflight]]
[[Category:Cold War nuclear missiles of the United States]]
[[Category:Intercontinental ballistic missiles of the United States]]
[[Category:Atlas (rocket family)]]
[[Category:Single-stage-to-orbit]]
[[Category:Military equipment introduced in the 1950s]]
[[Category:Convair]]
[[Category:General Dynamics]]