Titan (rocket family)

Most of the Titan rockets were the Titan II ICBM and their civilian derivatives for NASA. The Titan II used the LR-87-5 engine, a modified version of the LR-87, that used a hypergolic propellant combination of nitrogen tetroxide (NTO) for its oxidizer and Aerozine 50 (a 50/50 mix of hydrazine and unsymmetrical dimethylhydrazine (UDMH) instead of the liquid oxygen and RP-1 propellant of the Titan I.

The first Titan II guidance system was built by AC Spark Plug. It used an inertial measurement unit made by AC Spark Plug derived from original designs from the Charles Stark Draper Laboratory at MIT. The missile guidance computer (MGC) was the IBM ASC-15. When spares for this system became hard to obtain, it was replaced by a more modern guidance system, the Delco Electronics Universal Space Guidance System (USGS). The USGS used a Carousel IV IMU and a Magic 352 computer.[3] The USGS was already in use on the Titan III space launcher when work began in March 1978 to replace the Titan II guidance system. The main reason was to reduce the cost of maintenance by $72 million per year; the conversions were completed in 1981.[4]

Liquid oxygen is dangerous to use in an enclosed space, such as a missile silo, and cannot be stored for long periods in the booster oxidizer tank. Several Atlas and Titan I rockets exploded and destroyed their silos. The Martin Company was able to improve the design with the Titan II. The RP-1/LOX combination was replaced by a room-temperature fuel whose oxidizer did not require cryogenic storage. The same first-stage rocket engine was used with some modifications. The diameter of the second stage was increased to match the first stage. The Titan II's hypergolic fuel and oxidizer ignited on contact, but they were highly toxic and corrosive liquids. The fuel was Aerozine 50, a 50/50 mix of hydrazine and UDMH, and the oxidizer was NTO.

There were several accidents in Titan II silos resulting in loss of life and/or serious injuries.

In August 1965, 53 construction workers were killed in fire in a missile silo northwest of Searcy, Arkansas. The fire started when hydraulic fluid used in the Titan II was ignited by a welding torch.[5][6]

The liquid fuel missiles were prone to developing leaks of their toxic propellants. At a silo outside Rock, Kansas, an oxidizer transfer line carrying NTO ruptured on August 24, 1978.[7] An ensuing orange vapor cloud forced 200 rural residents to evacuate the area.[8] A staff sergeant of the maintenance crew was killed while attempting a rescue and a total of twenty were hospitalized.[9]

Another site at Potwin, Kansas leaked NTO oxidizer in April 1980 with no fatalities,[10] and was later closed.

In September 1980, at Titan II silo 374-7 near Damascus, Arkansas, a technician dropped an 8 lb (3.6 kg) socket that fell 70 ft (21 m), bounced off a thrust mount, and broke the skin of the missile's first stage,[11] over eight hours prior to an eventual explosion.[12] The puncture occurred about 6:30 p.m.[13] and when a leak was detected shortly after, the silo was flooded with water and civilian authorities were advised to evacuate the area.[14] As the problem was being attended to at around 3 a.m.,[13] leaking rocket fuel ignited and blew the 8,000 lb (3,630 kg) nuclear warhead out of the silo. It landed harmlessly several hundred feet away.[15][16][17] There was one fatality and 21 were injured,[18] all from the emergency response team from Little Rock AFB.[13][19] The explosion blew the 740-ton launch tube cover 200 ft (60 m) into the air and left a crater 250 feet (76 m) in diameter.[20]

The 54 Titan IIs[21] in Arizona, Arkansas, and Kansas[18] were replaced by 50 MX "Peacekeeper" solid-fuel rocket missiles in the mid-1980s; the last Titan II silo was deactivated in May 1987.[22] The 54 Titan IIs had been fielded along with a thousand Minuteman missiles from the mid-1960s through the mid-1980s.

A number of Titan I and Titan II missiles have been distributed as museum displays across the United States.

The most famous use of the civilian Titan II was in the NASA Gemini program of crewed space capsules in the mid-1960s. Twelve Titan II GLVs were used to launch two U.S. uncrewed Gemini test launches and ten crewed capsules with two-person crews. All of the launches were successful.

Starting in the late 1980s, some of the deactivated Titan IIs were converted into space launch vehicles to be used for launching U.S. Government payloads. Titan 23G rockets consisted of two stages burning liquid propellant. The first stage was powered by one Aerojet LR87 engine with two combustion chambers and nozzles, and the second stage was propelled by an LR91. On some flights, the spacecraft included a kick motor, usually the Star-37XFP-ISS; however, the Star-37S was also used.[23]

Thirteen were launched from Space Launch Complex 4W (SLC-4W) at Vandenberg Air Force Base starting in 1988.[23] The final such vehicle launched a Defense Meteorological Satellite Program (DMSP) weather satellite on 18 October 2003.[24]

• 
  Titan II ICBM
• 
  Titan II GLV
• 
  Titan 23G

The first guidance system for the Titan III used the AC Spark Plug company IMU (inertial measurement unit) and an IBM ASC-15 guidance computer from the Titan II. For the Titan III, the ASC-15 drum memory of the computer was lengthened to add 20 more usable tracks, which increased its memory capacity by 35%.[28]

The more-advanced Titan IIIC used a Delco Carousel VB IMU and MAGIC 352 Missile Guidance Computer (MGC).[29][30]

The Titan IIIA was a prototype rocket booster and consisted of a standard Titan II rocket with a Transtage upper stage.

The Titan IIIB with its different versions (23B, 24B, 33B, and 34B) had the Titan III core booster with an Agena D upper stage. This combination was used to launch the KH-8 GAMBIT series of intelligence-gathering satellites. They were all launched from Vandenberg Air Force Base, due south over the Pacific into polar orbits. Their maximum payload mass was about 7,500 lb (3,000 kg).[31]

The powerful Titan IIIC used a Titan III core rocket with two large strap-on solid-fuel boosters to increase its launch thrust and maximum payload mass. The solid-fuel boosters that were developed for the Titan IIIC represented a significant engineering advance over previous solid-fueled rockets, due to their large size and thrust, and their advanced thrust-vector control systems.

The Titan IIID was the Vandenberg Air Force Base version of the Titan IIIC, without a Transtage, that was used to place members of the Key Hole series of reconnaissance satellites into polar low Earth orbits.

The Titan IIIE, with a high-specific-impulse Centaur upper stage, was used to launch several scientific spacecraft, including both of NASA's two Voyager space probes to Jupiter, Saturn and beyond, and both of the two Viking missions to place two orbiters around Mars and two instrumented landers on its surface.[32][33]

The Titan 34D featured Stage 1 and Stage 2 stretched with more powerful UA1206 solid motors. A variety of upper stages were available, including the Inertial Upper Stage, the Transfer Orbit Stage, and the Transtage.[34] The Titan 34D made its maiden flight in the year of 1982 on the 30th of October with two DSCS defense communications satellites for the United States Department of Defense (DOD).

Derived from the Titan 34D and originally proposed as a medium-lift expendable launch system for the US Air Force, who selected the Delta II instead. Development was continued as a commercial launch system, and the first rocket flew in 1990. The Commercial Titan III differed from the Titan 34D in that it had a stretched second stage, and a larger payload fairing to accommodate dual satellite payloads.

The Titan IIIM was intended to launch the Manned Orbiting Laboratory and other payloads. Development was cancelled in 1969. The projected UA1207 solid booster rockets were eventually used on the Titan IV.[35][36]

• 
  Titan IIIA
• 
  Titan 23B
• 
  Titan IIIC
• 
  Titan IIID
• 
  Titan IIIE
• 
  Titan 34D
• 
  Commercial Titan 3