Hubbry Logo
HGM-25A Titan IHGM-25A Titan IMain
Open search
HGM-25A Titan I
Community hub
HGM-25A Titan I
logo
8 pages, 0 posts
0 subscribers
Be the first to start a discussion here.
Be the first to start a discussion here.
HGM-25A Titan I
HGM-25A Titan I
HGM-25A Titan I
View on Wikipedia
from Wikipedia
Titan I
Launch of a Titan I SM/567.8-90 ICBM
from Cape Canaveral, Florida
FunctionICBM
ManufacturerMartin Company
Country of originUnited States
Cost per launch$1.5 million
Size
Height31 m (102 ft)
Diameter3.05 m (10.0 ft)
Mass105,140 kg (231,790 lb)
Stages2
Launch history
StatusRetired
Launch sitesCape Canaveral LC-15,
LC-16, LC-19, LC-20
Vandenberg AFB OSTF SLTF LC-395
Total launches70 (suborbital)
Success(es)53 (suborbital)
Failure17 (suborbital)
First flight6 February 1959
Last flight5 March 1965
First stage
Engines1 LR87-AJ-3
Thrust1,900 kN (430,000 lbf)
Specific impulse290 seconds
Burn time140 seconds
PropellantRP-1/LOX
Second stage
Engines1 LR91-AJ-3
Thrust356 kN (80,000 lbf)
Specific impulse308 seconds
Burn time155 seconds
PropellantRP-1/LOX
[edit on Wikidata]

The Martin Marietta SM-68A/HGM-25A Titan I was the United States' first multistage intercontinental ballistic missile (ICBM), in use from 1959 until 1962. Though the SM-68A was operational for only three years, it spawned numerous follow-on models that were a part of the U.S. arsenal and space launch capability. The Titan I was unique among the Titan models in that it used liquid oxygen and RP-1 as propellants; all subsequent versions used storable propellants instead.

Originally designed as a backup in case the U.S. Air Force's SM-65 Atlas missile development ran into problems, the Titan was ultimately beaten into service by Atlas. Deployment went ahead anyway to more rapidly increase the number of missiles on alert and because the Titan's missile silo basing was more survivable than Atlas.

The succeeding LGM-25C Titan II served in the U.S. nuclear deterrent until 1987 and had increased capacity and range in addition to the different propellants.

History

[edit]

By January 1955, the size of nuclear weapons had been shrinking dramatically, allowing the possibility of building a bomb that could be carried by a missile of reasonable size. The Titan I program began on the recommendation of the Scientific Advisory Committee.[1] The committee presented to the United States Air Force (USAF) their findings of the technical feasibility to develop weapons (bombs) and their delivery systems (intercontinental range ballistic missiles) that were completely invulnerable to "surprise" attack.

The reduction in the mass of nuclear warheads allowed full coverage of the entire Sino-Soviet land mass, and the missile control capabilities were also upgraded. The Titan I would be fully independent in controlled flight from launch to the ballistic release of the warhead, which would descend to its target by the combination of gravity and air resistance alone. In May 1955 the Air Materiel Command invited contractors to submit proposals and bids for the two stage Titan I ICBM, formally beginning the program. In September 1955, The Martin Company was declared the contractor for the Titan missile. In early October the Air Force's Western Development Division was ordered to start work.[2] The Titan was developed in parallel with the Atlas (SM-65/HGM-16) ICBM, serving as a backup with potentially greater capabilities and an incentive for the Atlas contractor to work harder.[3] Martin was selected as the contractor due to its proposed organization[4] and method of igniting a liquid fueled engine at high altitude.[5]

The Titan I was initially designated as a bomber aircraft (B-68),[6] but was later designated SM-68 Titan and finally HGM-25A in 1962.

Program management

[edit]

The previous strategic missile programs of the Air Force had been administered using the "single prime contractor concept" (later called the weapon system concept).[7] This had resulted in three badly botched programs; the programs of the Snark, Navaho and RASCAL missiles had slipped an average of 5 years and had cost overruns of 300 per cent or more.[8] In response, the Teapot Committee was tasked with evaluating requirements for ballistic missiles and methods of accelerating their development. As a result of the ensuing recommendations, the USAF established the Western Development Division and Brigadier General Bernard Schriever was detailed to command it. Schriever devised an entirely new organization for program management. The Air Force was to act as "prime contractor," the Ramo-Woolridge Corporation was contracted to provide systems engineering and technical direction of all ballistic missiles. The airframe contractor also would assemble the sub-systems provided by other Air Force contractors.[9] At the time, this new organization was very controversial.[10]

The Titan I represented an evolution of technology when compared to the Atlas missile program, but shared many of the Atlas' problems. The liquid oxygen oxidizer could not be stored for long periods of time, increasing the response time as the missile had to be raised out of its silo and loaded with oxidizer before a launch could occur. The main improvements of the Titan I over the first Atlas's deployed were vertical storage in a fully underground silo and an improved fully internal inertial guidance system. Later Atlas E/F models were equipped with what would have been the Titan I's guidance system[11] The Titan I would be deployed with the Bell Labs radio-inertial guidance system.[12][13]

Budgetary problems

[edit]

The Titan, proposed as a fallback in case the Atlas failed, was by December 1956 accepted by some as a "principal ingredient of the national ballistic missile force."[14] At the same time, others pushed for the cancellation of the Titan program almost from the beginning, arguing that it was redundant.[15] Despite counterarguments that the Titan offered greater performance and growth potential than the Atlas as a missile and space launch vehicle,[15] the Titan program was under constant budgetary pressure. In the summer of 1957 budget cuts led Secretary of Defense Wilson to reduce the Titan production rate from the proposed seven per month to two a month, which left the Titan as a research and development program only.[16] However, the Sputnik crisis, which started 5 October 1957, ended any talk of canceling Titan. Priority was restored, and 1958 saw increases in funding and plans for additional Titan squadrons.[17]

Flight testing

[edit]

The Titan I flight testing consisted of the first stage only Series I, the cancelled Series II, and Series III with the complete missile.[18]

A total of 62 flight test missiles were constructed in various numbers. The first successful launch was on 5 February 1959 with Titan I A3, and the last test flight was on 29 January 1962 with Titan I M7. Of the missiles produced, 49 launched and two exploded: six A-types (four launched), seven B-types (two launched), six C-types (five launched), ten G-types (seven launched), 22 J-types (22 launched), four V-types (four launched), and seven M-types (seven launched). Missiles were tested and launched in Florida at Cape Canaveral Air Force Station from Launch Complexes LC15, LC16, LC19, and LC20.[19][18][20]

The four A-type missile launches with dummy second stages all occurred in 1959 and were carried out on 6 February, 25 February, 3 April, and 4 May. The guidance system and stage separation all performed well, and aerodynamic drag was lower than anticipated. Titan I was the first program to have a new missile succeed on the initial attempt, which left launch crews unprepared for the series of failures that followed. Missile B-4 exploded from a LOX pump failure during a static firing at Martin's Denver test stand in May and assorted other mishaps occurred in the following two months.[21]

Missile B-5 was intended to launch from LC-19 as the first flight article Lot B missile, incorporating most Titan I missile systems but with a dummy warhead. A planned launch on July 31 was scrubbed due to fuel system problems. At about noon on August 5, B-5 was launched. The missile rose about ten feet before the engines shut down and it fell back onto LC-19 in a fiery explosion. Postflight investigation found that the hold-down bolts released prematurely, causing B-5 to lift before full thrust rise had been achieved. A still-attached umbilical sent a shutdown command to the engines. LC-19 was badly damaged and would not be used again for six months.[21]

Further problems occurred over the next several months. Missiles continued to be damaged through careless personnel mistakes and General Osmond Ritland sent Martin an angry letter calling their handling of the Titan program "inexcusable." Ritland's disciplinary blast had little effect for the time being. On December 10, the first attempt was made to launch a Lot C missile, which would be a complete Titan I with all systems and a detachable warhead. Missile C-3 was prepared for launch but much like with B-5, a premature shutdown command was sent due to failure of an umbilical to detach, fortunately the missile had not been released from the pad. The umbilical was quickly repaired but any relief at having avoided near-disaster was short-lived.

At 1:11 PM EST on December 12, Missile C-3 launched from LC-16. The engines started, but the missile almost immediately disappeared in a fireball. The mishap was quickly traced to the Range Safety destruct charges on the first stage inadvertently going off. Martin technicians had moved the activator relay into a vibration-prone area during repair work on the missile and testing confirmed that the shock from the pad hold-down bolts firing was enough to set off the relay. The pad was not as badly damaged as LC-19 had been from the B-5 mishap as C-3 had not actually lifted and it was repaired in only two months.[22]

On 2 February 1960, LC-19 returned to action as Missile B-7A marked the first successful flight of a Titan with a live upper stage—this was a composite missile as B-7's original upper stage was damaged months earlier in an accident and it was replaced with the upper stage from Missile B-6 which had had its first stage damaged in another accident. On 5 February, LC-16 returned to action by hosting Missile C-4. The second attempt at a Lot C Titan failed at T+52 seconds when the guidance compartment collapsed, causing the RVX-3 reentry vehicle to separate.[22] The missile pitched down and the first stage LOX tank ruptured from aerodynamic loads, blowing the stage to pieces. After the first stage destroyed itself, the second stage separated and began engine ignition, sensing that normal staging had taken place. With no attitude control, it began tumbling end-over-end and quickly lost thrust. The stage plummeted into the Atlantic Ocean some 30–40 miles downrange [23] After the successful flight of Missile G-4 on 24 February, Missile C-1's second stage failed to ignite on 8 March due to a stuck valve preventing the gas generator from starting.[24] The last Lot C missile was C-6 which flew successfully on April 28. The Lot G missiles incorporated several design improvements to correct problems encountered on previous Titan launches. On 1 July, the newly opened LC-20 hosted its first launch when Missile J-2, an operational prototype, was flown. Unfortunately, a broken hydraulic line caused the Titan's engines to gimbal hard left almost as soon as the tower was cleared.[25] The missile pitched over and flew onto a near-horizontal plane when Range Safety sent the destruct command at T+11 seconds. The burning remains of the Titan impacted 300 meters from the pad in an enormous fireball. The piece of plumbing responsible for the missile failure was retrieved—it had popped out of its sleeve resulting in loss of first stage hydraulic pressure. The sleeve was not tight enough to hold the hydraulic line in place, and the pressure being imparted into it at liftoff was enough to pop it loose. Examination of other Titan missiles found more defective hydraulic lines, and the Missile J-2 debacle caused a wholesale review of manufacturing processes and improved parts testing.[26]

The next launch at the end of the month (Missile J-4) suffered premature first stage shutdown and landed far short of its planned impact point. Cause of the failure was a LOX valve closing prematurely, which resulted in the rupture of a propellant duct and thrust termination. Missile J-6 on 24 October set a record by flying 6100 miles. The J series resulted in minor changes to alleviate the second stage shutting down prematurely or failing to ignite.[25]

The string of failures during 1959–60 led to complaints from the Air Force that Martin–Marietta weren't taking the Titan project seriously (since it was just a backup to the primary Atlas ICBM program) and displayed an indifferent, careless attitude that resulted in easily avoidable failure modes such as Missile C-3's range safety command destruct system relays being placed in a vibration-prone area.[22][27]

Titan I missile emerges from its silo at Vandenberg Operational System Test Facility in 1960.

In December, Missile V-2 was undergoing a flight readiness test in a silo at Vandenberg Air Force Base, California. The plan was to load the missile with propellant, raise it up to firing position, and then lower it back into the silo. Unfortunately, the silo elevator collapsed, causing the Titan to fall back down and explode. The blast was so violent that it ejected a service tower from inside the silo and launched it some distance into the air before coming back down.[28][29][30]

A total of 21 Titan I launches took place during 1961, with five failures. On 20 January 1961, Missile AJ-10 launched from LC-19 at CCAS. The flight ended in failure when an improper disconnect of a pad umbilical caused an electrical short in the second stage. The Titan performed well through the first stage burn, but after second stage separation, the fuel valve to the gas generator failed to open, preventing engine start. Missiles AJ-12 and AJ-15 in March were lost due to turbopump problems. Missile M-1's second stage lost thrust when the hydraulic pump failed. Missile SM-2 experienced early first stage shutdown; although the second stage burn was successful, it had to run to propellant depletion instead of a timed cutoff. The added stress of this operation apparently resulted in a failure of either the gas generator or turbopump, as the vernier solo phase ended prematurely. Missile M-6's second stage failed to start when an electrical relay malfunctioned and reset the ignition timer.[20][31]

With attention shifting to the Titan II, there were only six Titan I flights during 1962, with one failure, when Missile SM-4 (21 January) experienced an electrical short in the second stage hydraulic actuator, which gimbaled hard left at T+98 seconds. Staging was performed successfully, but the second stage engine failed to start.[31]

Twelve more Titan Is were flown in 1963–65, with the finale being Missile SM-33, flown on 5 March 1965. The only total failure in this last stretch of flights was when Missile V-4 (1 May 1963) suffered a stuck gas generator valve and loss of engine thrust at liftoff. The Titan fell over and exploded on impact with the ground.[32][33]

Although most of the Titan I's teething problems were worked out by 1961, the missile was already eclipsed not only by the Atlas, but by its own design successor, the Titan II, a bigger, more powerful ICBM with storable hypergolic propellants. The launch pads at Cape Canaveral were quickly converted for the new vehicle. Vandenberg Launch Complex 395 continued to provide for operational test launches. The last Titan I launch was from LC 395A silo A-2 in March 1965.[34] After a brief period as an operational ICBM, it was retired from service in 1965 when Defense Secretary Robert McNamara made the decision to phase out all first generation cryogenically fueled missiles in favor of newer hypergolic and solid-fueled models. While decommissioned Atlas (and later Titan II) missiles were recycled and utilized for space launches, the Titan I inventory was stored and eventually scrapped.[35]

Characteristics

[edit]
"The Time of the Titan" - official USAF missile development promotional film.

Produced by the Glenn L. Martin Company (which became "The Martin Company" in 1957), Titan I was a two-stage, liquid-fueled ballistic missile with an effective range of 6,101 nautical miles (11,300 km). The first stage delivered 300,000 pounds (1,330 kN) of thrust, the second stage 80,000 pounds (356 kN). The fact that Titan I, like Atlas, burned Rocket Propellant 1 (RP-1) and liquid oxygen (LOX) meant that the oxidizer had to be loaded onto the missile just before launch from an underground storage tank, and the missile raised above ground on the enormous elevator system, exposing the missile for some time before launch. The complexity of the system combined with its relatively slow reaction time – fifteen minutes to load, followed by the time required to raise and launch the first missile.[36] Following the launch of the first missile the other two could reportedly be fired at 7+1⁄2-minute intervals.[37] Titan I utilized radio-inertial command guidance. The inertial guidance system originally intended for the missile was instead eventually deployed in the Atlas E and F missiles.[38] Less than a year later the Air Force considered deploying the Titan I with an all-inertial guidance system but that change never occurred.[39] (The Atlas series was intended to be the first generation of American ICBMs and Titan II (as opposed to Titan I) was to be the second generation deployed). The Titan 1 was controlled by an autopilot which was informed of the missile's attitude by a rate gyro assembly consisting of 3 gyroscopes. During the first minute or two of the flight a pitch programmer put the missile on the correct path.[37] From that point the AN/GRW-5 guidance radar tracked a transmitter on the missile. The guidance radar fed missile position data to the AN/GSK-1 (Univac Athena) missile guidance computer in the Launch Control Center.[40][41] The guidance computer used the tracking data to generate instructions which were encoded and transmitted to the missile by the guidance radar. Guidance input/output between the guidance radar and guidance computer occurred 10 times a second.[42] Guidance commands continued for the stage 1 burn, the stage 2 burn and the vernier burn ensuring the missile was on the correct trajectory and terminating the vernier burn at the desired velocity. The last thing the guidance system did was to determine if the missile was on the right trajectory and pre-arm the warhead which then separated from the second stage.[43] In case of the failure of the guidance system at one site, the guidance system at another site could be used to guide the missiles of the site with the failure.[44]

Titan I also was the first true multi-stage (two or more stages) design. The Atlas missile had all three of its main rocket engines ignited at launch (two were jettisoned during flight) due to concerns about igniting rocket engines at high altitude and maintaining combustion stability.[45] Martin, in part, was selected as the contractor because it had "recognized the 'magnitude of the altitude start problem' for the second stage and had a good suggestion for solving it."[4] Titan I's second-stage engines were reliable enough to be ignited at altitude, after separation from the first stage booster. The first stage, besides including heavy fuel tanks and engines, also had launch interface equipment and the launch pad thrust ring with it. When the first stage had finished consuming its propellant, it dropped away, thereby decreasing the mass of the vehicle. Titan I's ability to jettison this mass prior to the ignition of the second stage meant that Titan I had a much greater total range (and a greater range per pound of second-stage fuel) than Atlas, even if the total fuel load of Atlas had been greater.[46] As North American Aviation's Rocketdyne Division was the only manufacturer of large liquid propellent rocket engines the Air Force Western Development Division decided to develop a second source for them. Aerojet-General was selected to design and manufacture the engines for the Titan. Aerojet produced the LR87-AJ-3 (booster) and LR91-AJ-3 (sustainer). George P. Sutton wrote "Aerojet's most successful set of large LPRE was that for the booster and sustainer stages of the versions of the Titan vehicle".[47]

The warhead of the Titan I was an AVCO Mk 4 re-entry vehicle containing a W38 thermonuclear warhead with a yield of 3.75 megatons which was fuzed for either air burst or contact burst. The Mk 4 RV also deployed penetration aids in the form of mylar balloons which replicated the radar signature of the Mk 4 RV.[48]

Specifications

[edit]
  • Liftoff thrust: 1,296 kN
  • Total mass: 105,142 kg
  • Core diameter: 3.1 m
  • Total length: 31.0 m
  • Development cost: $1,643,300,000 in 1960 dollars.
  • Flyaway cost: $1,500,000 each, in 1962 dollars.
  • Total production missiles built: 163 Titan 1s; 62 R&D Missiles – 49 launched & 101 Strategic Missiles (SMs) – 17 launched.
  • Total deployed strategic missiles: 54.
  • Titan base cost: $170,000,000 (US$ 1.81B in 2024)[49]

First Stage:

  • Gross mass: 76,203 kg
  • Empty mass: 4,000 kg
  • Thrust (vac): 1,467 kN
  • Isp (vac): 290 s (2.84 kN·s/kg)
  • Isp (sea level): 256 s (2.51 kN·s/kg)
  • Burn time: 138 s
  • Diameter: 3.1 m
  • Span: 3.1 m
  • Length: 16.0 m
  • Propellants: liquid oxygen (LOX), kerosene
  • Number of engines: two Aerojet LR87-3

Second Stage:

  • Gross mass: 28,939 kg
  • Empty mass: 1,725 kg
  • Thrust (vac):356 kN
  • Isp (vac): 308 s (3.02 kN·s/kg)
  • Isp (sea level): 210 s (2.06 kN·s/kg)
  • Burn time: 225 s
  • Diameter: 2.3 m
  • Span: 2.3 m
  • Length: 9.8 m
  • Propellants: liquid oxygen (LOX), kerosene
  • Number of engines: one Aerojet LR91-3

Athena guidance computer

[edit]

The UNIVAC Athena computer calculated ground commands to transmit to the Titan missile as part of Western Electric's missile guidance system. The Athena was the "first transistorized digital computer to be produced in numbers." It consisted of ten cabinets plus console on a 13.5 by 20 foot (4.1 by 6 m) floor plan. It used radar tracking of the missile to compute Titan flight data to the necessary burn-out point to start a ballistic trajectory toward the target. On-board Titan attitude control rolled the missile to maintain the missile antenna aligned to the ground antenna. Computer commands were transmitted to the missile from a ground transmitter a "quarter mile out" (400 m).[50] Completed in 1957, the Athena weighed 21,000 pounds (11 short tons; 9.5 t).[51][52]

The Athena computer used a Harvard architecture design with separate data and instruction memories by Seymour Cray at Sperry Rand Corporation and cost about $1,800,000.[53]

Used with the computer were the:

  • AN/GSK-1 Computer Set Console (OA-2654)[54]
  • Friden, Inc. terminal with paper tape equipment[51]
  • "massive motor-generator set with 440 volt 3 phase AC input [that] weighed over 2 tons" at remote locations[55]
  • input from one of two large AN/GRW-5 Western Electric radars in silos each with "20 foot (6 m) tall antenna" raised prior to launch and locked to the raised Titan's "missileborne antenna".[56][50]

The "battleshort" mode ("melt-before-fail") prevented fail-safe circuits such as fuses from deactivating the machine e.g., during a missile launch.[57] The last Athena-controlled launch was a Thor-Agena missile launched in 1972 from Vandenberg Air Force Base in California, the last of over 400 missile flights using the Athena.[58][59]

Service history

[edit]

The production of operational missiles began during the final stages of the flight test program.[31] An operational specification SM-2 missile was launched from Vandenberg AFB LC-395-A3 on 21 January 1962, with the M7 missile launched on the last development flight from Cape Canaveral's LC-19 on 29 January 1962.[60] There were 59 XSM-68 Titan Is manufactured I in 7 developmental lots. One hundred and one SM-68 Titan I missiles were produced to equip six squadrons of nine missiles each across Western America. Fifty-four missiles were in silos in total, with one missile as a spare on standby at each squadron, bringing to 60 in service at any one time.[61] Titan was originally planned for a 1 X 10 (one control center with 10 launchers) "soft" site.[62] In mid-1958 it was decided that the American Bosh Arma all-inertial guidance system designed for Titan would, because production was insufficient, be assigned to Atlas and the Titan would switch to radio-inertial guidance.[63] The decision was made to deploy Titan squadrons in a "hardened" 3 X 3 (three sites with one control center and three silos each) to reduce the number of guidance systems required. (Radio-inertial guided Atlas D squadrons were similarly sited).[64]

Although Titan I's two stages gave it true intercontinental range and foreshadowed future multistage rockets, its propellants were dangerous and hard to handle. Cryogenic liquid oxygen oxidizer had to be pumped aboard the missile just before launch, and complex equipment was required to store and move this liquid.[65] In its brief career, a total of six USAF squadrons were equipped with the Titan I missile. Each squadron was deployed in a 3x3 configuration, which meant each squadron controlled a total of nine missiles divided among three launch sites, with the six operational units spread across the western United States in five states: Colorado (with two squadrons, both east of Denver), Idaho, California, Washington, and South Dakota. Each missile complex had three Titan I ICBM missiles ready to launch at any given time.

HGM-25A Titan I is located in the United States
568th SMS
568th SMS
569th SMS
569th SMS
724th SMS
724th SMS
725th SMS
725th SMS
850th SMS
850th SMS
851st SMS
851st SMS
class=notpageimage|
Map Of HGM-25A Titan I Operational Squadrons
Larson AFB, Washington
Mountain Home AFB, Idaho
Lowry AFB, Colorado
Lowry AFB, Colorado
Ellsworth AFB, South Dakota
Beale AFB, California

Silos

[edit]

Weapon System 107A-2 was a weapon system. It encompassed all of the equipment and even the bases for the Titan I strategic missile. The Titan I was first American ICBM designed to be based in underground silos, and it gave USAF managers, contractors and missile crews valuable experience building and working in vast complexes containing everything the missiles and crews needed for operation and survival. The complexes were composed of an entry portal, control center, powerhouse, terminal room, two antenna silos for the ATHENA guidance radar antennas, and three launchers each composed of: three equipment terminals, three propellant terminals, and three missile silos. All connected by an extensive network of tunnels.[66] Both antenna terminals and all three launchers were isolated with double door blast locks the doors of which could not be open at the same time. This was to ensure that if there was an explosion in a missile launcher or the site was under attack, only the exposed antenna and/or missile silo would be damaged.[67]

The launch crew was composed of a missile combat crew commander, missile launch officer (MLO), guidance electronics officer (GEO), ballistic missile analyst technician (BMAT), and two electrical power production technicians (EPPT).[68] There were also a cook and two Air Police.[69] During normal duty hours there was a site commander, site maintenance officer, site chief, job controller/expediter, tool crib operator, power house chief, three pad chiefs, three assistant pad chiefs, another cook and more air police. There could be a number of electricians, plumbers, power production technicians, air conditioning technicians, and other specialist when maintenance was being performed.[69]

These early complexes while safe from a nearby nuclear detonation, however, had certain drawbacks. First, the missiles took about 15 minutes to fuel, and then, one at a time, had to be lifted to the surface on elevators for launching and guidance, which slowed their reaction time. Rapid launching was crucial to avoid possible destruction by incoming missiles. Even though Titan complexes were designed to withstand nearby nuclear blasts, antennas and missiles extended for launch and guidance were quite susceptible to even a relatively distant miss.[70] The missiles sites of a squadron were placed at least 17 (usually 20 to 30) miles apart so that a single nuclear weapon could not take out two sites.[71] The sites also had to be close enough that if a site's guidance system failed it could "handover" its missiles to another site of the squadron.[72][73]

The distance between the antenna silos and the most distant missile silo was between 1,000 and 1,300 feet (400 m). These were by far the most complex, extensive and expensive missile launch facilities ever deployed by the USAF.[74][75][76] Launching a missile required fueling it in its silo, and then raising the launcher and missile out of the silo on an elevator. Before each launch, the guidance radar, which was periodically calibrated by acquiring a special target at a precisely known range and bearing,[77] had to acquire a radio on the missile (missile guidance set AN/DRW-18, AN/DRW-19, AN/DRW-20, AN/DRW-21, or AN/DRW-22).[78][79] When the missile was launched, the guidance radar tracked the missile and supplied precise velocity range and azimuth data to the guidance computer, which then generated guidance corrections that were transmitted to the missile. Because of this, the complex could only launch and track one missile at a time, although another could be elevated while the first was being guided.

Retirement

[edit]

When the storable-fueled Titan II and the solid-fueled Minuteman I were deployed in 1963, the Titan I and Atlas missiles became obsolete. They were retired from service as ICBMs in early 1965.[80][81]

The final launch from Vandenberg Air Force Base (VAFB) occurred on 5 March 1965. At that time, the disposition of the 101 total production missiles was as follows:[citation needed]

  • 17 were test launched from VAFB (September 1961 – March 1965)
  • one was destroyed in Beale AFB Site 851-C1 silo explosion 24 May 1962
  • 54 were deployed in silos on 20 January 1965
  • 29 were in storage at SBAMA[82]

(three at VAFB, one at each of five bases, one at Lowry, and 20 in storage at SBAMA elsewhere)

The 83 surplus missiles remained in inventory at Mira Loma AFS. It did not make economic sense to refurbish them as SM-65 Atlas missiles with similar payload capacities had already been converted to satellite launchers. About 33 were distributed to museums, parks and schools as static displays (see list below). The remaining 50 missiles were scrapped at Mira Loma AFS near San Bernardino, CA; the last was broken up in 1972, in accordance with the SALT-I Treaty of 1 February 1972.[82]

By November 1965 the Air Force Logistics Command had determined that the cost of modifying the widely dispersed sites to support other ballistic missiles was prohibitive, and attempts were made to find new uses.[83] By Spring 1966 a number of possible uses and users had been identified. By 6 May 1966 the Air Force wanted to retain 5 Titan sites and the General Services Administration had earmarked 1 for possible use. The USAF removed equipment it had uses for, the rest was offered to other government agencies.[84] Eventually no sites were retained and all were salvaged. The chosen method was the Service and Salvage contract, which required the contractor to remove the equipment the government wanted before proceeding with scrapping.[85] This accounts for the varied degree of salvage at the sites today. Most are sealed today, with one in Colorado that is easily entered but also very unsafe.[86] One is open for tours.[87]

The 26 ATHENA guidance computers, when declared surplus by the federal government, went to various United States universities. The one at Carnegie was used as an undergraduate project until 1971, when the former electrical engineering undergraduate students (Athena Systems Development Group) orchestrated its donation to the Smithsonian Institution. One remained in use at Vandenberg AFB until it guided a last Thor-Agena launch in May 1972. It had guided over 400 missiles.[88][89]

On 6 September 1985 Strategic Defense Initiative (AKA "Star Wars" program), a scrapped Titan I Second Stage was used in a Missile Defense test. The MIRACL Near Infrared Laser, at White Sands Missile Range, NM was fired at a stationary Titan I second stage that was fixed to the ground. The second stage burst and was destroyed by the laser blast. The second stage was pressurized with nitrogen gas to 60-psi and did not contain any fuel or oxidizer. A follow-up test 6 days later was conducted on a scrapped Thor IRBM, its remnants reside at the SLC-10 Museum at Vandenberg AFB.[90]

  • Titan-I ICBM SM vehicles being destroyed at Mira Loma AFS for the SALT-1 Treaty
    Titan-I ICBM SM vehicles being destroyed at Mira Loma AFS for the SALT-1 Treaty
  • Titan-I ICBM SM vehicles being destroyed at Mira Loma AFS for the SALT-1 Treaty
    Titan-I ICBM SM vehicles being destroyed at Mira Loma AFS for the SALT-1 Treaty
  • Titan-I ICBM SM vehicles being destroyed at Mira Loma AFS for the SALT-1 Treaty
    Titan-I ICBM SM vehicles being destroyed at Mira Loma AFS for the SALT-1 Treaty

Static displays and articles

[edit]
Titan I in Cordele, Georgia, I-75 exit 101

Of the 33 Titan I Strategic Missiles and two (plus five possible) Research and Development Missiles that were not launched, destroyed, or scrapped, several survive today:[citation needed]

  • B2 57-2691 Cape Canaveral Air Force Space & Missile Museum, Florida Horizontal
  • R&D (57–2743) Colorado State Capitol display 1959 (SN belongs to a Bomarc) Vertical
  • R&D G-type Science and Technology Museum, Chicago 21 June 1963 Vertical
  • SM-5 60-3650 Lompoc? Horizontal
  • SM-49 60-3694 Cordele, Georgia (west side of I-75, exit 101 at U.S. Route 280). Vertical
  • SM-53 60-3698 Site 395-C Museum, Vandenberg AFB, Lompoc, Ca. (from March AFB) Horizontal
  • SM-54 60-3699 Strategic Air Command & Aerospace Museum, Ashland, Nebraska. Vertical
  • SM-61 60-3706 Gotte Park, Kimball, NE (only first stage standing, damaged by winds in '96?) Vertical (damaged by winds 7/94 ?)
  • SM-63 60-3708 In storage at Edwards AFB (still there?) Horizontal
  • SM-65 61-4492 NASA Ames Research Center, Mountain View, California. Horizontal
  • SM-67 61-4494 Titusville High School, Titusville, Florida (on Route US-1) removed, was horizontal
  • SM-69 61-4496 (full missile) Discovery Park of America in Union City, Tennessee. It has been restored to correct external appearance and is now vertically displayed on the grounds. Its upper stage engine was also restored and on display.
  • SM-70 61-4497 Veterans Home, Quincy, IL Vertical (removed and sent to DMAFB for destruction in May 2010)
  • SM-71 61-4498 U.S. Air Force Museum, now AMARC (to go to PIMA Mus.) Horizontal
  • SM-72 61-4499 Florence Regional Airport Air and Space Museum, Florence, South Carolina. Horizontal
  • SM-73 61-4500 former Holiday Motor Lodge, San Bernardino (now missing?). Horizontal
  • SM-79 61-4506 former Oklahoma State Fair Grounds, Oklahoma City, Oklahoma. 1960s Horizontal
  • SM-81 61-4508 Kansas Cosmosphere, Hutchinson, Kansas. In storage
    SM-69 61-4496 at Discovery Park of America in Union City, TN.
  • SM-86 61-4513 Beale AFB (not on display, was horizontal, removed 1994) Horizontal
  • SM-88 61-4515 (st. 1) Pima Air & Space Museum, outside DM AFB, Tucson, Arizona, now WPAFB Horizontal
  • SM-89 61-4516 (st. 2) Pima Air Museum, outside DM AFB, Tucson, Arizona, now WPAFB Horizontal
  • SM-92 61-4519 (st. 1) Kansas Cosmosphere, Hutchinson, Kansas. (acq. 11/93 from MCDD) Vertical (st 1 mate to SM-94 st 1)
  • SM-93 61-4520 (st. 2) SLC-10 Museum, Vandenberg AFB, Lompoc, Ca. Horizontal (only stage 2)
  • SM-94 61-4521 (st. 1) Kansas Cosmosphere, Hutchinson, Kansas. (acq. 6/93 from MCDD) Vertical (st 1 mate to SM-92 st 1)
  • SM-96 61-4523 South Dakota Air and Space Museum, Ellsworth AFB, Rapid City, South Dakota. Horizontal
  • SM-101 61-4528 Estrella Warbirds Museum, Paso Robles, CA (2nd stage damaged) Horizontal
    LR87 engine
  • SM-?? (stg. 2 only) former SDI laser test target (whereabouts?)
  • SM-?? (stg. 1 only) former Spaceport USA Rocket Garden, Kennedy Space Center, Florida. Vert. (stg 1 mated to stg 1 below)
  • SM-?? (stg. 1 only) former Spaceport USA Rocket Garden, Kennedy Space Center, Florida. Vert. (stg 1 mated to stg 1 above)
  • SM-?? (stg. 1 only) Science Museum, Bayamon, Puerto Rico Vert. (stg 1 mated to stg 1 below)
  • SM-?? (stg. 1 only) Science Museum, Bayamon, Puerto Rico (top half from Bell's Junkyard) Vert. (stg 1 mated to stg 1 above)
  • SM-?? (full missile) former Outside main gate of White Sands Missile Range, N.M. false report? Vertical
  • SM-?? (full missile) Spacetec CCAFS Horizontal

Note: Two stacked Titan-1 first stages created a perfect illusion of a Titan-2 Missile for museums above.

Prospective manned flights

[edit]

The Titan I was considered for use as the first missile to put a man in space. Two of the firms responding to an Air Force "Request for Proposal" for "Project 7969," an early USAF project to "Put a Man in Space Soonest (MISS)". Two of the four firms which responded, Martin and Avco, proposed using Titan I as the booster.[91][92]

See also

[edit]

References

[edit]

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

HGM-25A Titan I

View on Grokipedia
from Grokipedia
The HGM-25A Titan I was the Air Force's first operational multistage (ICBM), a two-stage liquid-fueled weapon system developed by the (later ) and designed for launch from hardened underground complexes. Standing 98 feet tall with a of , it utilized kerosene and propellants in its first stage and / nitrogen tetroxide in the second, achieving a maximum range of approximately 6,300 miles while carrying a reentry vehicle equipped with either a W38 thermonuclear of 3.75 megatons yield or a variable up to 4 megatons. Deployed across six squadrons totaling 54 missiles at five bases in , , , Washington, and from 1961 to 1965, the Titan I enhanced U.S. strategic deterrence during the by providing survivable, dispersed launch capabilities resistant to overpressures up to 100 psi, though its pre-launch fueling sequence—requiring about 15 minutes—rendered it vulnerable to preemptive strikes compared to emerging solid-fuel systems. As the largest ICBM ever fielded by the U.S., it marked a critical advancement in multistage rocketry and silo-based operations, yielding operational insights that informed successors like the Titan II while exposing challenges such as cryogenic hazards, complex maintenance demands exceeding 80 daily procedures per missile, and several launch facility accidents that underscored the risks of liquid-fueled designs.

Development History

Inception and Strategic Requirements

The development of the HGM-25A Titan I stemmed from U.S. Air Force requirements in the mid-1950s for a reliable intercontinental ballistic missile (ICBM) to counter the growing Soviet nuclear threat and reduce dependence on vulnerable strategic bombers. In January 1955, the Air Force initiated the Titan program as a parallel effort to the SM-65 Atlas, explicitly positioning it as a backup should Atlas encounter insurmountable technical issues. On July 12, 1955, Headquarters USAF issued Specific Operational Requirement (SOR) 104, outlining the need for both Atlas and Titan to deliver a multi-megaton warhead over intercontinental distances with sufficient accuracy for deterrence. This reflected a causal shift toward missile-based second-strike capabilities, prioritizing hardened, rapid-response systems over manned bombers that could be preemptively destroyed. Soviet advancements intensified the urgency, as the successful launch of on October 4, 1957, demonstrated Moscow's mastery of long-range rocketry and fueled perceptions of a "" in U.S. intelligence assessments, despite later evidence showing Soviet ICBM deployments lagged behind American efforts. Under the Eisenhower administration, the Titan program received accelerated funding and priority following these events, with the October 1955 contract award to emphasizing a two-stage, liquid-fueled design for enhanced reliability and payload capacity. The strategic imperative was grounded in empirical deterrence logic: ensuring a survivable retaliatory force capable of penetrating Soviet defenses, thereby stabilizing . Key performance mandates included a minimum range of 5,500 nautical miles (approximately 10,200 km) to reach targets across and a reentry vehicle accommodating warheads in the multi-megaton yield range, such as the 4-megaton W38 or later options, to maximize destructive potential against hardened military and urban sites. These specifications addressed the causal vulnerabilities of early bomber-centric strategies, where alert times exceeded hours, by enabling silo-launched missiles with minutes-to-launch readiness, thus complicating enemy first-strike calculations.

Program Execution and Contractors

The United States Air Force initiated the Titan I program under Weapons System (WS) 107A-2 in October 1955, selecting the Glenn L. Martin Company as the prime contractor to develop a backup intercontinental ballistic missile parallel to the Convair Atlas, emphasizing a multistage liquid-fueled design for enhanced reliability over the single-stage Atlas approach. The Martin Company, formerly known as Glenn L. Martin Aircraft Company, managed overall airframe integration, assembly, and system testing at facilities in Baltimore, Maryland, and Denver, Colorado, drawing on its prior experience with military aircraft and early missile prototypes. Subcontractors included Aerojet General Corporation for the liquid rocket engines, which required coordination to ensure compatibility with Martin's airframe and staging mechanisms. Early program execution focused on transitioning from to production-scale , with Martin overseeing parallel efforts in component fabrication and development to meet requirements for rapid deployment. A key management decision was the adoption of hardened underground basing in , prioritizing survivability against Soviet preemptive strikes over above-ground pads used in initial Atlas deployments, which necessitated additional contracts for and handling systems. This shift involved resource allocation toward capable of withstanding overpressures, influencing contractor timelines for integrating the 's 98-foot length and 220,000-pound fueled weight into vertical launch configurations. The overall development phase incurred costs exceeding $1.6 billion in then-year dollars, reflecting investments in tooling, fabrication, and subcontractor integration amid the program's emphasis on empirical validation of multistage separation and cryogenic handling at scale. Martin's role extended to coordinating with specialized firms for guidance subsystems, ensuring inertial navigation components met precision requirements for intercontinental ranges without reliance on external radio commands. By 1959, the first operational HGM-25A missiles were accepted from Martin, marking the transition from development to squadron delivery under Ballistic Systems Division oversight.

Testing Program and Technical Hurdles

The testing program for the HGM-25A Titan I began in late 1958 with ground-based static firings of the first-stage engines to validate propulsion performance under restrained conditions. The first free-flight test occurred on February 6, 1959, from Launch Complex 15, employing an XSM-68 prototype with an operational first stage and a dummy second stage filled with water to simulate mass; this launch successfully demonstrated ascent but highlighted early integration challenges. Subsequent tests progressively incorporated full staging and reentry elements, culminating in the final development flight on January 29, 1962. A total of approximately 67 flight tests were conducted from through 1962, with early launches suffering from failures such as control losses and structural ruptures, yielding initial success rates below 50%; however, iterative refinements elevated overall reliability to over 75%, with the final qualification series exceeding 80% success by addressing root causes like anomalies and guidance errors through empirical and component redesigns. Stage separation proved a primary hurdle, as the multistage design—unlike the semi-staged Atlas—required precise pyrotechnic sequencing and rail-guided disengagement; initial attempts in 1959 with dummy stages succeeded partially, but full two-stage separation failures, including post-burnout collisions, persisted until resolution via enhanced interstage mechanisms in early 1960 flights. Cryogenic fuel management presented additional causal challenges, stemming from the volatility of (LOX) paired with , which demanded insulated storage to mitigate boil-off and precise loading sequences to avoid overpressurization or leaks during silo integration; these issues contributed to pad explosions in preliminary tests, resolved by adjustments like improved venting and remote fueling protocols that still necessitated 15-20 minutes for upload, limiting alert responsiveness compared to solid-fuel alternatives. Reentry vehicle validation for the Mk 4 configuration, incorporating ablative heat shielding and stabilization fins, commenced in August 1960, with successful intercontinental-range demonstrations—such as a 4,335-nautical-mile on February 24, 1960—confirming delivery accuracy but exposing aerodynamic instabilities at hypersonic speeds, mitigated through wind-tunnel correlations and iterative nose-cone refinements. Post-1961 tests shifted to operational configurations, empirically verifying range and yield potential while underscoring the program's reliance on liquid propulsion's inherent preparation delays as a fundamental constraint.

Technical Design

Physical and Performance Specifications

The HGM-25A Titan I measured 98 feet (29.87 meters) in length, with a first-stage diameter of 10 feet (3.05 meters) and a second-stage diameter of 8 feet (2.44 meters). Its launch weight was approximately 220,000 pounds (99,790 kilograms). The missile employed a two-stage , distinguishing it from predecessors like the through discrete staging for improved reliability and payload capacity. Equipped with a single W53 thermonuclear warhead in a reentry vehicle, the Titan I delivered a yield of 9 megatons. It achieved a maximum range of over 6,300 miles (10,000 kilometers), with terminal speeds exceeding Mach 20 (approximately 15,000 ). Accuracy was limited by guidance technology, yielding a (CEP) of about 1 to 2 nautical miles, suitable primarily for city-level strikes rather than hardened military targets.
SpecificationValue
Length98 ft (29.87 m)
Diameter (Stage 1)10 ft (3.05 m)
Diameter (Stage 2)8 ft (2.44 m)
Launch Weight~220,000 lb (99,790 kg)
Warhead1 × W53 (9 MT yield)
Range>6,300 mi (10,000 km)
Speed>Mach 20
CEP~1-2 nautical miles

Propulsion and Staging

The HGM-25A Titan I utilized a two-stage liquid rocket propulsion system fueled by RP-1 (a refined kerosene) and liquid oxygen (LOX) in both stages, selected for their high energy density and performance potential despite logistical challenges. The first stage incorporated two fixed Aerojet LR87-AJ-1 engines arranged in a clustered configuration, collectively generating 300,000 lbf (1,334 kN) of sea-level thrust through dual-thrust-chamber assemblies gimbaled for vector control. This setup achieved a specific impulse of approximately 256 seconds at sea level, enabling rapid initial acceleration while the cryogenic LOX demanded specialized handling to prevent boil-off and ensure stable pre-launch storage. The second stage employed a single LR91-AJ-1 engine delivering 80,000 lbf (356 kN) of vacuum-optimized , with a exceeding 300 seconds to maximize velocity increment for insertion into suborbital trajectories. Integrated vernier thrusters on the second stage provided attitude control during separation and flight, compensating for the absence of continuous first-stage steering post-burnout. The cryogenic combination yielded superior relative to contemporaneous storable liquids, but imposed causal trade-offs in operational complexity, including extended fueling sequences and heightened sensitivity to environmental factors compared to solid or hypergolic alternatives in later ICBMs. Stage separation was initiated post-first-stage burnout via pyrotechnic mechanisms that explosively decoupled the interstage structure, allowing the second to ignite and achieve efficient burnout velocities validated in developmental flight tests. This process ensured minimal performance loss, with the design prioritizing reliability over simplicity to meet intercontinental ballistic requirements, though it amplified demands for precise timing and protocols inherent to LOX systems.

Guidance and Avionics

The HGM-25A Titan I utilized a hybrid radio-inertial , featuring an onboard inertial platform with gyroscopes and accelerometers for initial trajectory stabilization and velocity measurement during the phase, augmented by radio command corrections from ground stations throughout the boost period. This approach compensated for limitations in 1950s-era all-inertial technology, which had not yet achieved sufficient reliability for standalone ICBM use, by integrating real-time ground-computed adjustments based on radar tracking data. Ground-based processing relied on the UNIVAC digital computer, an early transistorized system capable of handling complex ballistic calculations to derive correction signals transmitted to the missile's onboard receiver for pitch, yaw, and roll adjustments. The inertial components, including a stabilized platform, provided foundational autonomous derived from integrating and angular rates, while the radio link enabled larger lateral corrections than pure inertial methods allowed at the time. This configuration yielded an operational accuracy of approximately 1,400 meters (CEP), reflecting empirical test data under controlled conditions and establishing a baseline for subsequent fully inertial upgrades in the Titan II.

Silo Infrastructure and Launch Mechanisms

The HGM-25A Titan I was deployed in underground complexes each containing three hardened , designed under the WS-107A program to enhance survivability compared to the above-ground launch pads of the earlier . Each measured approximately 155 feet in depth and 40 feet in diameter, constructed from to withstand overpressures of up to 100 pounds per (psi). The featured multiple blast doors, including two heavy doors at the surface, and were connected via underground tunnels to support facilities, providing against nuclear blasts that would overwhelm unhardened or surface-based systems. Launch mechanisms relied on massive hydraulic elevators capable of lifting the 220,000-pound from depths to the surface launch position. In the launch sequence, the —stored unfueled to mitigate propellant hazards—was elevated to the open position, where ( and ) were loaded into the stages over about 15 minutes, followed by ignition of the first-stage engines from dedicated ground pads. This surface fueling and ignition process, distinct from later silo-launched designs, prioritized rapid erection for firing while leveraging 's depth for storage security, though it extended preparation time relative to fully contained systems. The silo basing choice stemmed from 1950s strategic assessments recognizing the Atlas's vulnerability to preemptive strikes, mandating hardened underground facilities for improved second-strike capability under evolving requirements. of each three-silo complex cost approximately $40 million in 1960 dollars, reflecting the demands of deep excavation, reinforcement, and integrated launch . This investment aimed to ensure missile survivability against predicted Soviet attack overpressures, though the 100 psi rating limited effectiveness against advanced threats compared to subsequent designs hardened to higher thresholds.

Operational Service

Deployment and Squadron Operations

The HGM-25A Titan I was deployed across six strategic missile squadrons, comprising a total of 54 missiles distributed in three geographic areas: near in , in , and Larson Air Force Base in Washington. These squadrons—568th, 569th, 724th, 725th, 850th, and 851st—operated under the 703d, 456th, and 567th Strategic Aerospace Wings, respectively. Initial rollout commenced in early 1961, with the first squadron achieving operational alert status that March, followed by progressive activation of remaining units. Full deployment of all missiles was attained by mid-1962. Each squadron managed nine missiles dispersed across three hardened underground launch facilities, with three vertical per facility connected by a network of tunnels for loading and access. Facilities were manned around the clock by crews stationed in reinforced control centers, ensuring continuous readiness amid the demands of liquid-fueled systems requiring on-site storage of and kerosene. Warhead integration, involving the W38 or later W53 thermonuclear devices, followed stringent protocols separate from assembly to mitigate risks during sustainment. The system's peak operational phase spanned 1962 to 1965, coinciding with elevated alert postures during the Cuban Missile Crisis from to 28, 1962, when raised its forces to high readiness in response to Soviet actions. Daily operations emphasized rigorous maintenance cycles to address the complexities of logistics and silo pressurization, supporting rapid launch sequencing from hardened sites.

Procedural Protocols and Crew Training

Operational protocols for the HGM-25A Titan I enforced the for all critical actions, including of launch orders and enabling missile systems, to prevent unauthorized operations. Launch preparation commenced upon receipt of authenticated alerts, involving the loading of (LOX) into pre-fueled RP-1 tanks, silo door opening, missile elevation via hydraulic elevators, and final system checks, typically requiring 15 to 20 minutes for the first missile at a complex with subsequent missiles prepared in about 7.5 minutes each. These procedures integrated positive control measures from (SAC), mandating secure communications links for code validation to ensure compliance with national command authority and avert accidental or rogue launches. Crew training occurred primarily at Vandenberg Air Force Base under dedicated squadrons such as the 394th and 395th Strategic Missile Squadrons, focusing on tactical execution in simulated environments. Emphasis was placed on cryogenic safety protocols for handling, including hazard recognition, usage, and emergency response to prevent asphyxiation or risks inherent to liquid-fueled systems. Silo-based simulations replicated full launch sequences, alert responses, and equipment familiarization, with crews rotating in teams typically comprising two s—a launch officer and guidance officer—supported by enlisted personnel for and power operations, totaling 10-15 members per complex to maintain continuous readiness across shifts. Regular alert drills tested crew proficiency in rapid response scenarios, simulating Soviet first-strike conditions to validate the 15-30 minute preparation timeline under duress, reinforcing procedural discipline without compromising positive control safeguards. Declassified SAC directives underscored the integration of human factors training to mitigate errors in high-stress environments, prioritizing verifiable command chains over speed alone.

Role in U.S. Nuclear Deterrence

The HGM-25A Titan I bolstered U.S. nuclear deterrence by strengthening the land-based component of the strategic triad, complementing Atlas ICBMs and manned bombers with its -launched configuration. By 1963, 54 Titan I missiles were operational, each equipped with a W-38 thermonuclear warhead yielding 3.75 megatons, collectively providing about 200 megatons of ICBM payload. The hardened underground s, the first such for U.S. ICBMs, were engineered to withstand overpressures of up to 100 pounds per square inch, enhancing prospects for post-attack retaliation and aligning with principles through improved second-strike survivability. Titan I deployments countered Soviet advances, including the R-7 ICBM operational since 1959 and the R-16 introduced in 1962, by offering a range exceeding 5,500 nautical miles sufficient to reach primary Eurasian targets from continental U.S. bases. This capability supported strategic parity by ensuring a portion of U.S. retaliatory forces could endure initial strikes, as the missile's multistage liquid-fueled design permitted heavy payloads deliverable after protection. In practice, during the October 1962 , Titan I units maintained 72-hour alerts, underscoring operational readiness and contributing to crisis resolution without escalation to nuclear conflict. Strategic evaluations affirmed the system's role in deterrence stability, yet highlighted risks from the 15- to 30-minute launch sequence—requiring elevation and loading—that could enable Soviet preemption if launch preparations were detected.

Effectiveness and Challenges

Reliability Metrics and Flight Outcomes

The HGM-25A Titan I achieved an overall flight success rate of 75.71% across 70 launches conducted between February 1959 and March 1965, with 53 successful flights and 17 failures. This encompassed developmental tests, including the first successful launch on February 6, 1959 (using a dummy second stage), the initial two-stage flight in January 1960, and subsequent silo-lift evaluations through 1961. Over 60 s were expended in testing and training, highlighting the program's emphasis on iterative validation despite early challenges like stage separation malfunctions that caused aborts in initial full-range attempts. Operational reliability post-deployment in 1962 hovered around 75%, constrained by recurrent issues including cryogenic fuel leaks from handling and hydraulic system failures, which demanded frequent maintenance and reduced mean time between failures for propulsion components. These stemmed causally from the non-storable propellants' sensitivity to thermal stresses and vibration, exacerbating silo-based fueling protocols. During alerts from 1962 to 1965, such as the 72-hour continuous readiness posture at Ellsworth AFB during the October 1962 , launch assurance varied due to these complexities, with cryogenic boil-off and hydraulic line vulnerabilities occasionally delaying elevation and ignition sequences. In contrast to the contemporaneous Atlas series, which experienced higher initial failure rates from similar liquid-fueled instabilities, Titan I's post-1962 operational yielded more consistent outcomes, with fewer stage ignition aborts after refinements to and systems. USAF assessments linked these improvements to targeted hardening against cryogenic-induced faults, though overall metrics underscored the inherent trade-offs of multistage designs versus emerging solid-fuel alternatives.

Comparative Strategic Value

The HGM-25A Titan I demonstrated superior silo survivability compared to the Soviet (SS-6 Sapwood), which relied on vulnerable open-air launch pads susceptible to preemptive strikes. Titan I missiles were stored in hardened underground capable of withstanding overpressures of approximately 100-200 psi from nearby nuclear detonations, a feature absent in the R-7's surface-based infrastructure. This underground basing pioneered protected ICBM deployment, enhancing second-strike credibility and influencing subsequent deterrence architectures by prioritizing hardened fixed sites over exposed pads. In terms of staging efficiency, the Titan I's two-stage liquid-fueled design allowed for optimized weight distribution and a maximum range of about 10,000-11,300 km, outperforming the R-7's clustered booster configuration, which limited practical operational range to 8,000-9,500 km despite similar payload capacities of 3-5 megatons. Relative to the emerging series, the Titan I offered advantages in initial payload delivery with a 3.75-megaton W38 , but lagged in launch responsiveness due to its propellants and sequence, requiring 15-20 minutes from alert to first ignition versus the Minuteman's near-instantaneous solid-fuel launch. Declassified assessments indicate that while Soviet numerical deployments fueled "" perceptions—exaggerating R-7 operational readiness to as few as 10-25 launchers by 1961—the Titan I contributed to U.S. deterrence parity through reliable basing and range, countering actual Soviet lags in hardened systems. However, the Titan I's extended preparation reduced its utility in rapid-escalation crises, as noted in post-deployment evaluations favoring solid-propellant transitions for quicker reaction times. Overall, the Titan I's strategic value lay in bridging early ICBM vulnerabilities, achieving effective equivalence (around 3-4 megatons) against Soviet variability while establishing survivable that outlasted the R-7's obsolescence by the early . This countered hysteria over Soviet leads, with U.S. deployments emphasizing qualitative edges in hardening over quantitative claims, though transition to Minuteman underscored limitations in handling and salvo timing.

Cost Overruns and Logistical Drawbacks

The Titan I program's development costs escalated significantly from initial projections, totaling approximately $1.64 billion in dollars due to extensive research, testing, and adaptations for hardened deployment. Flyaway costs per reached about $1.5 million in 1962 dollars, reflecting the integration of advanced staging, guidance, and structural reinforcements necessitated by underground storage requirements. of the 18 launch complexes, each housing three missiles, averaged $44.4 million per site, driven by the engineering demands of blast-resistant , systems, and fueling infrastructure. These overruns stemmed primarily from the inherent complexities of pioneering a survivable, silo-launched ICBM, including iterative designs to withstand nuclear blasts and ensure rapid elevation for fueling, rather than solely administrative factors. The program's aggregate expenditure neared $2 billion when factoring in procurement of 163 operational s and supporting R&D vehicles, underscoring the premium for technological maturation in a high-stakes deterrence context. Logistically, the Titan I's dependence on cryogenic liquid oxygen (LOX) alongside RP-1 kerosene imposed stringent supply chain demands, as LOX's extreme cold (-183°C) mandated specialized cryogenic tankers, on-site purification to avert from or impurities, and constant monitoring to mitigate boil-off losses during storage. Unlike storable hypergolic s in successor systems, this required missiles to be raised from silos, fueled sequentially in a 15-minute process, complicating readiness compared to the Atlas missile's aboveground but similarly cryogenic operations. Such handling vulnerabilities heightened operational friction, including risks of instability in remote, hardened facilities, though these were offset by the propellant's higher enabling greater range and .

Incidents and Safety Record

Documented Accidents and Casualties

On May 24, 1962, an occurred during defueling operations at Site 851-C1, part of the 851st Strategic Missile Squadron at near , destroying the Titan I missile and damaging the silo; no fatalities resulted, though nearly 60 personnel were treated for minor injuries and smoke inhalation. The incident involved a that propagated during the removal of propellant. Earlier test launches at encountered explosive failures, including on August 14, 1959, when a Titan I detonated on the pad shortly after ignition due to a premature engine shutdown, and on December 12, 1959, when another vehicle exploded just above the pad after stage destruct activation; no casualties were reported in these events. A separate accident on August 7, 1961, at a Titan I silo near Denver, Colorado (associated with the 569th Strategic Missile Squadron at ), involved the collapse of a 57-ton blast door during maintenance, killing five workers and injuring eight others; this mechanical failure was not linked to propellant ignition. At least one additional fatality occurred during ground handling at a Titan I facility, involving ignition of signaling flares in the second stage during a system check, though the exact date and site remain tied to contractor records at testing areas. Across documented incidents, total casualties numbered fewer than ten personnel, underscoring the hazards of cryogenic s and complex mechanisms despite reinforced safety protocols.

Root Causes and Systemic Vulnerabilities

The primary design flaws contributing to Titan I failure modes centered on its cryogenic (LOX) and refined petroleum-1 () propellant system, which necessitated fueling immediately prior to launch and exposed components to extreme thermal stresses. LOX's super-chilled state at approximately -183°C embrittled non-compatible seals and valves, predisposing them to cracking or premature actuation under pressure differentials during propellant transfer, as documented in operational engineering analyses of early liquid-fueled ICBMs. This contrasted sharply with solid-fuel alternatives like the Minuteman, which eliminated such cryogenic handling vulnerabilities by storing propellants in a ready-to-fire configuration without external pumping or temperature management. Ignition risks further compounded these propellant-related issues, as 's flammability combined with 's oxidizing properties created potential for from minor contaminants, static discharge, or mechanical sparks during the 15- to 20-minute fueling sequence conducted underground. Unlike storable hypergolic propellants adopted in successors, / required precise ignition via pyrotechnic starters, but leaks or incomplete mixing heightened explosion hazards absent in inert solid grains. These flaws were inherent to pioneering multistage for hardened deployment, where rapid pressurization of tanks amplified stress on aging infrastructure. Systemic vulnerabilities emerged from the interdependent silo architecture, including hydraulic elevators interfacing directly with the fueled silo; fluid leaks from these high-pressure systems could migrate into propellant areas, serving as ignition sources or eroding structural integrity during elevation to surface launch position. assessments noted that such couplings—necessitated by the need to fuel below ground for —introduced cascading failure paths, where a single hydraulic fault could jeopardize the entire launch complex, a avoided in simpler above-ground or solid-fuel setups. While these risks reflected the trade-offs of early cryogenic technology's push for higher over storability, they underscored causal linkages between design ambition and operational brittleness, independent of isolated human errors.

Post-Incident Reforms

Following the May 24, 1962, explosion at Titan I Launch Complex 4C near , which destroyed a and damaged the silo due to a probable fuel or oxidizer leak during fueling operations, the U.S. investigated the incident and adjusted operational protocols to address handling risks of the 's cryogenic and propellants in the first stage, as well as hypergolic propellants in upper stages. These changes emphasized stricter procedures for loading, leak monitoring, and to isolate hazards, alongside reinforced crew training on rapid silo venting and equipment checks to prevent ignition sources. While specific technical modifications like added redundant leak sensors were limited by the missile's , the reforms achieved partial success by averting additional major silo failures through the remainder of the system's brief operational life from to 1965. Core vulnerabilities inherent to non-storable liquid fuels—such as boil-off requiring frequent replenishment and risks from leaks—persisted, contributing to no further catastrophic incidents but highlighting the need for fundamental redesigns. These experiences directly informed upgrades in the successor Titan II, which adopted storable hypergolic propellants throughout to eliminate cryogenic hazards and enable launch without surface elevation. Empirically, the adjusted protocols correlated with sustained operations absent repeat explosions or operational fatalities, validating incremental procedural fixes amid ongoing alert duties, though the system's overall safety profile remained constrained compared to emerging solid-fuel alternatives like Minuteman.

Deactivation and Aftermath

Retirement Rationale and Timeline

The retirement of the HGM-25A Titan I was primarily driven by its technological limitations in comparison to successor systems, particularly the need for extended fueling times with cryogenic and kerosene, which delayed launch readiness to approximately 15 minutes. In contrast, the Titan II utilized storable hypergolic propellants ( and nitrogen tetroxide), enabling silo launches in under one minute, while the solid-propellant Minuteman ICBM offered near-instantaneous alert status, reduced maintenance burdens from eliminating volatile liquids, and lower operational costs due to simplified and higher reliability in silo storage. These advancements aligned with Secretary of Defense Robert McNamara's force structure reviews emphasizing rapid-response capabilities and cost efficiency over the Titan I's initial advantages in payload capacity, rendering the first-generation liquid-fueled system strategically obsolete amid evolving deterrence requirements favoring against preemptive strikes. The phase-out was formally accelerated by McNamara's directive on May 16, 1964, with a November 1964 announcement mandating deactivation of all remaining first-generation ICBMs, including the Titan I, by the end of fiscal year 1965 (June 30). The process commenced with the 568th and 850th Strategic Missile Squadrons taking their missiles off alert on January 4, 1965, followed by progressive stand-downs across the six operational squadrons. The 851st SMS at Beale AFB concluded alert operations on February 10, 1965, marking the effective end of Titan I deployments, with full squadron inactivations completed by June 25, 1965, as sites transitioned to Minuteman forces for enhanced strategic flexibility.

Decommissioning Processes

The decommissioning of the HGM-25A Titan I began with the progressive inactivation of its six Strategic Missile Squadrons, starting January 4, 1965, at , , and concluding with the full deactivation of all units by June 25, 1965. This process encompassed 54 deployed missiles across 18 silos at nine launch complexes. Salvage teams systematically extracted the missiles and associated equipment from the sites, followed by the implosion of silos and the razing of launch control centers to neutralize hardened infrastructure. Propellant management involved draining the missiles' RP-1 kerosene fuel and from their tanks, a procedure necessitated by the cryogenic and flammable nature of these oxidizer-fuel combinations, prior to missile extraction and disposition. Nuclear warheads were separated from the reentry vehicles and transported for disassembly at specialized facilities, ensuring no operational readiness remained. The oversaw these operations through 1967, with the majority of airframes subsequently scrapped, though a limited number were retained for static displays or further testing. Attempts to repurpose select facilities for communications or other non-military uses proved minimal, as most sites were fully dismantled to prevent . The scale of the effort—addressing 54 missiles and supporting —proceeded without documented major accidents or releases, underscoring the controlled handling of hypergolic-adjacent but drainable liquid propellants, in contrast to later systems with more volatile fuels.

Efforts

Following deactivation in the mid-1960s, former HGM-25A Titan I sites were assessed for environmental contamination primarily from operational solvents like trichloroethene (TCE) used in missile maintenance and degreasing, rather than extensive propellant residues, as rapidly evaporates and spills were limited by design protocols. No or from warheads was detected at any Titan I complexes, as maintenance avoided dispersal. In , Titan I sites near underwent remedial investigations in the 1990s, identifying localized soil impacts from TCE and other volatiles; soil excavation addressed these, with no further remediation required by 2015, confirming plumes stable and below action levels. Feasibility studies for cleanup options concluded in 2010, prioritizing over aggressive extraction due to low migration rates and minimal off-site migration. At in , Titan I areas fell under the base-wide designation in 1989, but site-specific assessments showed contaminants confined to former footprints, with partial delistings by after verification of remedial effectiveness. The Titan 1-A facility near Lincoln, under the U.S. Army Corps of Engineers' Formerly Used Defense Sites program, detected TCE in in 1991, prompting ongoing monitoring and limited extraction; semiannual sampling through 2024 confirmed degradation products but concentrations posing no imminent health threats, with natural attenuation deemed sufficient alongside permeable reactive barriers tested in 2008. Washington sites near Larson Air Force Base similarly identified solvent plumes in the 1990s, addressed via soil removal and pumping, achieving closure standards by the early with post-remediation verification sampling. Remediation efforts across sites, totaling over $116 million for Titan and Atlas complexes by 2009 under the Defense Environmental Restoration Program, employed excavation for hot-spot soils, pump-and-treat for aquifers, and vapor intrusion mitigation, with per-complex expenditures ranging from $5-26 million depending on plume extent. Risk assessments consistently rated human exposure low, as contaminants remained below EPA maximum contaminant levels in downgradient wells and sites transitioned to unrestricted post-cleanup, countering unsubstantiated claims of persistent toxicity unfit for habitation. Ongoing U.S. Corps of Engineers reports, including 2025 updates for , affirm effective management without elevated cancer or non-cancer risks to nearby populations.

Enduring Impact

Technological Innovations and Influences

The HGM-25A Titan I represented a significant advancement in U.S. technology as the first multistage ICBM deployed by the , featuring a two-stage liquid-propellant design that achieved a range exceeding 6,300 miles. This configuration, with conventional tank construction and separation mechanisms, addressed limitations of earlier single-stage or partial-staging systems like the Atlas, enabling more efficient delivery to intercontinental distances. The missile's propulsion system utilized (refined ) and (kerolox) propellants, powered by twin LR87 engines on the first stage—each with gimbaled chambers producing 150,000 pounds of thrust—and a single engine on the second stage. These high-thrust engines emphasized storable yet volatile hypergolic upper-stage alternatives in later iterations but established reliable kerolox performance under constraints. Titan I's basing innovations included the first U.S. ICBM designed for hardened underground s, with 40-foot-diameter, 155-foot-deep launchers capable of withstanding overpressures from nearby nuclear detonations, though the required hydraulic elevation to the surface for ignition to mitigate damage from exhaust plumes. Its guidance employed a radio-inertial system developed by Bell Telephone Laboratories and , combining ground-based radio commands for coarse trajectory corrections with onboard inertial stabilization, achieving a of approximately 2 nautical miles. This hybrid approach improved upon purely radio-guided predecessors by reducing vulnerability to jamming while laying groundwork for fully inertial systems in successors. These features directly influenced subsequent U.S. strategic systems, with the Titan II evolving from the Titan I platform by adopting an all-inertial guidance system for greater autonomy and enabling direct silo launches, thereby enhancing rapid response capabilities. The hardened concept pioneered by Titan I informed Minuteman deployments, standardizing underground protection and contributing to the shift toward survivable, dispersed basing strategies. Propulsion and staging elements from the Titan series extended to vehicles, as the Titan II's engines and airframe adaptations formed the core of the Titan III and IV families, supporting over 150 orbital missions from 1964 to 2005 by leveraging proven multistage separation and . Overall, Titan I's empirical contributions bolstered U.S. nuclear deterrence by providing a verifiable second-strike capability alongside Atlas, helping achieve strategic parity with Soviet systems during the early era.

Preservation and Public Access

Several intact HGM-25A Titan I missiles survive as static displays in museums across the United States, with the National Museum of the U.S. Air Force in Dayton, Ohio, featuring a complete example in its Missile Gallery, accessible to the public since the museum's establishment of the exhibit. The Cape Canaveral Space Force Museum in Florida also maintains a Titan I in its outdoor Rocket Garden, preserving the missile's external structure for visitors to examine its multistage design and silo-launch adaptations. Additional examples include one at the South Dakota Air and Space Museum, restored in 2017 through collaborative efforts involving Air Force personnel to ensure structural integrity for long-term exhibition. These displays, numbering around five to ten intact airframes based on documented museum inventories, underscore the missile's role as the first U.S. multistage ICBM without operational remnants dominating public narratives of Cold War deterrence. Preservation initiatives have been led by U.S. Air Force historical programs and private aviation museums, which have conducted maintenance on surviving missiles to prevent corrosion from their liquid-fueled components, with repairs documented as recently as the mid-2010s. Environmental remediation at former Titan I sites during the 2020s, including groundwater cleanup at Colorado complexes under state oversight, has indirectly supported preservation by stabilizing abandoned facilities, though full silo access remains rare. Private entities, such as those operating missile silo properties in Washington state, offer limited specialized access like underwater tours of flooded complexes near Royal City, providing insight into underground infrastructure without standard public entry. Public access emphasizes the Titan I's engineering achievements, including its innovative silo-elevator system and cryogenic fueling, allowing visitors to appreciate the technical complexities of early ICBM deployment amid the era's strategic imperatives. These sites serve educational purposes by presenting unaltered artifacts that highlight causal factors in missile evolution, such as propellant handling challenges, rather than abstracted accounts of military history. No comprehensive Titan I silo tours akin to those for later systems exist as of 2025, with most former launch complexes in Colorado and Washington repurposed privately or left unrestored due to safety and cost constraints.

Adaptations for Non-Military Uses

Following its deactivation in June 1965, the HGM-25A Titan I saw negligible direct repurposing for civilian applications, with efforts constrained by the missile's cryogenic propellant system— paired with kerosene—which demanded extensive pre-launch fueling and risked boil-off, rendering it inefficient for sustained non-military operations compared to vehicles with storable hypergolics. Early conceptual studies around 1959 examined Titan variants for potential manned orbital roles, but these were deemed impractical due to fueling physics: the need to elevate, fuel, and launch within narrow windows incompatible with human-rated reliability standards, leading to prioritize surplus Atlas boosters already validated for suborbital and orbital flights like . No Titan I-based manned or unmanned missions materialized, as the design's silo-centric and volatility favored military rapid-response over adaptable pad launches. Post-retirement, isolated hardware reuse occurred in aeronautical ; a single Titan I stage arrived at NASA's in 1969 for static and dynamic tests simulating buffeting—aerodynamic oscillations during ascent through dense atmosphere—to inform future booster designs. This specimen, employed in and vibration studies, exemplified minor component-level adaptation but highlighted broader challenges: decommissioning protocols under the 1963 Limited Test Ban Treaty and SALT I preparations prioritized destruction over salvage, limiting availability for experimentation. Overall, non-military adaptations remained marginal, with no scalable programs emerging; the Titan I's enduring civilian value derived indirectly from foundational engineering—such as clustered staging and vectoring—informing evolved Titan II/III/IV iterations that executed over 300 space launches from 1964 to 2005, though these built on upgrades absent in the original model.

References

  1. https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/197978/martin-marietta-sm-68ahgm-25a-titan-i/
  2. https://designation-systems.net/dusrm/m-25.html
  3. https://www.nps.gov/articles/titan-icbm.htm
  4. https://spaceref.com/newspace-and-tech/titan-i-hgm-25a-overview/
  5. https://missilethreat.csis.org/missile/titan-i/
  6. https://www.afmissileers.org/Titan-ICBM
  7. http://www.astronautix.com/t/titani.html
  8. https://www.afmissileers.org/Titan-I
  9. https://www.spaceline.org/cape-canaveral-rocket-missile-program/titan-i-fact-sheet/
  10. https://www.enginehistory.org/Rockets/RPE06/RPE06.shtml
  11. https://en.missilery.info/missile/titan1
  12. http://www.astronautix.com/t/titan.html
  13. http://www.themilitarystandard.com/missile/titan1/overview.php
  14. https://forum.nasaspaceflight.com/index.php?topic=16412.0
  15. https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Fact-Sheets/Display/Article/579635/w53-thermonuclear-bomb/
  16. https://weaponsparade.com/weapon/titan-i-sm-68a-hgm-25a-icbm/
  17. https://www.nybooks.com/articles/1980/11/20/the-myth-of-missile-accuracy/
  18. http://www.silogic.com/Athena/Athena.html
  19. https://www.chromehooves.net/missile_silos.htm
  20. https://www.warrenmuseum.com/titan-1/
  21. https://www.atlasadastra.com/titan-1
  22. https://www.globalsecurity.org/wmd/systems/sm-68.htm
  23. https://www.beale.af.mil/News/Article-Display/Article/280017/cold-war-relics-deactivated-titan-1-missile-silos-surround-beale/
  24. https://www.afgsc.af.mil/News/Article-Display/Article/454741/sac-during-the-13-days-of-the-cuban-missile-crisis/
  25. https://www.acq.osd.mil/ncbdp/nm/NMHB2020rev/docs/NMHB2020rev.pdf
  26. https://nsarchive.gwu.edu/briefing-book/nuclear-vault/2019-02-25/how-strategic-air-command-would-go-nuclear-war
  27. http://mitp-content-server.mit.edu:18180/books/content/sectbyfn?collid=books_pres_0&fn=9780262661812_sch_0001.pdf&id=6028
  28. https://www.ellsworth.af.mil/News/Features/Display/Article/217586/titan-i-missiles-put-ellsworth-on-nuclear-map/
  29. http://www.themilitarystandard.com/missile/titan1/index.php
  30. https://nuke.fas.org/guide/russia/icbm/r-7.htm
  31. https://www.cia.gov/readingroom/collection/what-was-missile-gap
  32. https://history.state.gov/historicaldocuments/frus1961-63v07-09mSupp/d244
  33. https://www.brookings.edu/titan-i-missile-complex-construction/
  34. http://www.themilitarystandard.com/missile/titan1/siteconstruction.php
  35. https://www.nytimes.com/1962/05/25/archives/blast-wrecks-titan-and-its-silo-in-test.html
  36. https://www.newsreview.com/chico/content/house-of-titans/13342974/
  37. https://www.rocketreviews.com/titan-1-rocket-launch-exploded-dec-121959-8860.html
  38. https://www.nytimes.com/1961/08/08/archives/5-killed-8-hurt-at-missile-base-57ton-silo-door-crushes-workers-in.html
  39. https://ccspacemuseum.org/facilities/memorial-to-cape-industrial-fatalities/
  40. http://www.themilitarystandard.com/missile/titan1/beale_afb.php
  41. https://ntrs.nasa.gov/api/citations/19650014066/downloads/19650014066.pdf
  42. https://historicspacecraft.com/Rockets_Titan.html
  43. https://www.jcs.mil/Portals/36/Documents/History/Policy/Policy_V008.pdf
  44. https://www.facebook.com/AFNWC/photos/sep-8-1962-the-851st-strategic-missile-squadron-at-beale-afb-california-was-decl/2402036613402463/
  45. https://www.facebook.com/TitanMissileMuseum/posts/the-last-titan-i-icbm-squadrons-are-deactivated-on-this-day-60-years-ago-june-25/1121729466651397/
  46. https://www.historylink.org/File/10158
  47. https://cdphe.colorado.gov/hm/titan-1-missile-complexes
  48. https://www.waterboards.ca.gov/rwqcb5//water_issues/site_cleanup/beale_titan1a/titan1a_lincoln_fs.pdf
  49. https://www.nwo.usace.army.mil/Media/Fact-Sheets/Fact-Sheet-Article-View/Article/585123/denver-co-former-lowry-air-force-base-missile-site-1-complex-1b/
  50. https://cumulis.epa.gov/supercpad/SiteProfiles/index.cfm?fuseaction=second.cleanup&id=0800585
  51. https://www.federalregister.gov/documents/2012/03/13/2012-6031/national-oil-and-hazardous-substances-pollution-contingency-plan-national-priorities-list-partial
  52. https://www.spk.usace.army.mil/Missions/Military-Projects/FUDS/Titan-1-A-Missile-Site/
  53. https://www.spk.usace.army.mil/Media/News-Releases/Article/4064658/usace-releases-final-remedial-investigation-report-and-2024-semiannual-groundwa/
  54. https://apps.ecology.wa.gov/cleanupsearch/document/828
  55. https://www.cleveland.com/nation/2009/10/pollution_cleanup_proves_costl.html
  56. https://www.sacbee.com/news/local/article289704239.html
  57. https://www.spk.usace.army.mil/Portals/12/documents/military/FUDS/Titan%25201A/Admin_Record/J09CA110801_03.10_0529_a.pdf?ver=2XmaMBmwPD-7Z4pWrU9ioQ%253D%253D
  58. https://www.rfcafe.com/references/electronics-world/bell-telephone-laboratories-electronics-world-september-1960.htm
  59. https://titanmissilemuseum.org/about/titan-ii-history/
  60. https://www.nps.gov/articles/icbm-evolutions.htm
  61. https://www.nationalmuseum.af.mil/Visit/Museum-Exhibits/Missile-Gallery/
  62. https://ccspacemuseum.org/artifacts/titan-i/
  63. https://www.dvidshub.net/news/239326/preserve-display-educate-repairing-titan-sdasm
  64. https://www.underseaadventures.net/titan-i-missile-silo-silo-diving-dive-into-history.htm
  65. https://www.missilebases.com/titan-i-c1ypw/
  66. https://www.quora.com/I-understand-the-Titan-II-nuclear-missiles-used-incredibly-toxic-propellants-why-were-those-chosen-over-RP-1-and-liquid-oxygen
  67. https://spaceref.com/science-and-exploration/new-uses-for-an-old-titan-1-2/
  68. https://apps.dtic.mil/sti/tr/pdf/ADA296490.pdf
Add your contribution
Related Hubs
User Avatar
No comments yet.