The Titan IIIC was an expendable launch system used by the United States Air Force from 1965 until 1982. It was the first Titan booster to feature large solid rocket motors and was planned to be used as a launcher for the Dyna-Soar, though cancelled before any astronauts flew. The majority of the launcher's payloads were DoD satellites, for military communications and early warning, though one flight (ATS-6) was performed by NASA. The Titan IIIC was launched exclusively from Cape Canaveral while its sibling, the Titan IIID, was launched only from Vandenberg AFB.
Launch of a Titan IIIC
|Function||Medium-lift launch vehicle|
|Country of origin||United States|
|Height||137 ft (42 m)|
|Diameter||10 ft (3.05m)|
|Mass||1,380,510 lb (626,190 kg)|
|Payload to LEO||28,900 lb (13,100kg)|
|6,600 lb (3,000 kg)|
|2,650 lb (1,200 kg)|
|Launch sites||LC-40 & 41, CCAFS|
SLC-6, Vandenberg AFB
|First flight||18 June 1965|
|Last flight||6 March 1982|
|Boosters (Stage 0) – UA1205|
|Thrust||1,315,000 lbf (5,850 kN)|
|Specific impulse||263 secs|
|Burn time||115 seconds|
|Thrust||1,941.7 kN (436,500 lbf)|
|Burn time||147 seconds|
|Fuel||Aerozine-50 / N|
|Thrust||453.1 kN (101,900 lbf)|
|Burn time||205 seconds|
|Fuel||Aerozine-50 / N|
|Upper stage – Transtage|
|Thrust||16,000 lbf (71 kN)|
|Burn time||440 seconds|
|Fuel||Aerozine 50 / N|
The Titan rocket family was established in October 1955 when the Air Force awarded the Glenn L. Martin Company (later Martin Marietta and now Lockheed Martin) a contract to build an intercontinental ballistic missile (SM-68). It became known as the Titan I, the nation's first two-stage ICBM, and replaced the Atlas ICBM as the second underground, vertically stored, silo-based ICBM. Both stages of the Titan I used kerosene (RP-1) and liquid oxygen (LOX) as propellants. A subsequent version of the Titan family, the Titan II, was similar to the Titan I, but was much more powerful. Designated as LGM-25C, the Titan II was the largest USAF missile at the time and burned Aerozine 50 and nitrogen tetroxide (NTO) rather than RP-1 and LOX.
The Titan III family consisted of an enhanced Titan II core with or without solid rocket strap-on boosters and an assortment of upper stages. All Solid Rocket Motor (SRM)-equipped Titans (IIIC, IIID, IIIE, 34D, and IV) launched with only the SRMs firing at liftoff, the core stage not activating until T+105 seconds, shortly before SRM jettison. The Titan IIIA (an early test variant flown in 1964-65) and IIIB (flown from 1966-87 with an Agena D upper stage in both standard and extended tank variants) had no SRMs. The Titan III launchers provided assured capability and flexibility for launch of large-class payloads.
All Titan II/III/IV vehicles contained a special range safety system known as the Inadvertent Separation Destruction System (ISDS) that would activate and destroy the first stage if there was a premature second stage separation. Titans that carried Solid Rocket Boosters (SRBs) (Titan IIIC, IIID, 34D, and IV) had a second ISDS that consisted of several lanyards attached to the SRBs that would trigger and automatically destroy them if they prematurely separated from the core, said "destruction" consisting mainly of splitting the casings open to release the pressure inside and terminate thrust. The ISDS would end up being used a few times over the Titan's career.
Another slight modification to SRB-equipped Titans was the first stage engines being covered instead of the open truss structure on the Titan II/IIIA/IIIB. This was to protect the engines from the heat of the SRB exhaust.
Titan III/IV SRBs were fixed nozzle and for roll control, a small tank of nitrogen tetroxide was mounted to each motor. The N2O4 would be injected into the SRB exhaust to deflect it in the desired direction.
As the IIIC consisted of mostly proven hardware, launch problems were generally only caused by the upper stages and/or payload. The second launch in October 1965 failed when the Transstage suffered an oxidizer leak and was unable to put its payload (several small satellites) into the correct orbit. The third launch in December experienced a similar failure.
The fifth Titan IIIC (August 26, 1966) failed shortly after launch when pieces of the payload fairing started breaking off. Around 80 seconds, the remainder of the shroud disintegrated, causing loss of launch vehicle control as well as the payload (a group of IDCSP satellites intended to provide radio communication for the US Army in Vietnam). The automatic ISDS system activated when one of the SRBs broke away from the stack and destroyed the entire launch vehicle. The exact reason for the shroud failure was not determined, but the fiberglass payload shrouds used on the Titan III up to this point were replaced with a metal shroud afterwards.
A Titan IIIC in November 1970 failed to place its missile early warning satellite in the correct orbit due to a Transstage failure and a 1975 launch of a DSCS military comsat left in LEO by another Transstage failure.
On March 25, 1978, a launch of a DSCS satellite ended up in the Atlantic Ocean when the Titan second stage hydraulic pump failed, resulting in engine shutdown approximately 470 seconds after launch. The Range Safety destruct command was sent, but it was unclear if the stage received it or if it had already broken up by that point.
The first Titan IIIC flew on June 18, 1965 and was the most powerful launcher used by the Air Force until it was replaced by the Titan 34D in 1982. The last IIIC was launched in March 1982.
The Titan IIIC weighed about 1,380,000 lb (626,000 kg) at liftoff and consisted of a two-stage Titan core and upper stage called the Titan Transtage, both burning hypergolic liquid fuel, and two large UA1205 solid rocket motors.
The solid motors were ignited on the ground and were designated "stage 0". Each motor composed of five segments and was 10 ft (3.0 m) in diameter, 85 ft (26 m) long, and weighed nearly 500,000 lb (230,000 kg). They produced a combined 2,380,000 lbf (10,600 kN) thrust at sea level and burned for approximately 115 seconds. Solid motor jettison occurred at approximately 116 seconds.
The first core stage ignited about 5 seconds before SRM jettison. Designated the Titan 3A-1, this stage was powered by a twin nozzle Aerojet LR-87-AJ9 engine  that burned about 240,000 lb (110,000 kg) of Aerozine 50 and nitrogen tetroxide (NTO) and produced 1,941.7 kN (436,500 lbf) thrust over 147 seconds. The Aerozine 50 and NTO were stored in structurally independent tanks to minimize the hazard of the two mixing if a leak should have developed in either tank.
The upper stage, the Titan Transtage, also burned Aerozine 50 and NTO. Its two Aerojet AJ-10-138 engines were restartable, allowing flexible orbital operations including orbital trimming, geostationary transfer and insertion, and delivery of multiple payloads to different orbits. This required complex guidance and instrumentation. Transtage contained about 22,000 lb (10,000 kg) of propellant and its engines delivered 16,000 lbf (71 kN).
- Primary Function: Space booster
- Builder: Martin Marietta
- Power Plant:
- Length: 42 m
- Stage 0: 25.91 m
- Stage 1: 22.28 m
- Stage 2: 7.9 m
- Stage 3: 4.57 m
- Stage 0: 3.05 m
- Stage 1: 3.05 m
- Stage 2: 3.05 m
- Stage 3: 3.05 m
- Stage 0: Empty 33,798 kg/ea; Full 226,233 kg/ea
- Stage 1: Empty 5,443 kg; Full 116,573 kg
- Stage 2: Empty 2,653 kg; Full 29,188 kg
- Stage 3: Empty 1,950 kg; Full 12,247 kg
- Lift capability:
- Up to 28,900 lb (13,100 kg) into a low Earth orbit with 28 degrees inclination.
- Up to 6,600 lb (3,000 kg) into a geosynchronous transfer orbit when launched from Cape Canaveral Air Force Station, FL.
- Maximum takeoff weight: 626,190 kg
- Date deployed: June 1965.
- Launch sites: Cape Canaveral Air Force Station, FL., and Vandenberg Air Force Base, CA.
|Date/Time (GMT)||Launch Site||S/N||Payload||Outcome||Remarks|
|18 June 1965
|CCAFS LC-40||3C-7||N/A||Success||Transtage test flight|
|14 October 1965
|Failure||Transtage failed in low Earth orbit due to oxidizer tank leak|
|21 December 1965
|Partial failure||Transtage failed during 3rd burn due to stuck oxidizer valve; left payloads in GTO|
|16 June 1966
|CCAFS LC-41||3C-11||OPS-9311 (IDCSP)
|26 August 1966
|CCAFS LC-41||3C-12||7X IDCSP
|Failure||Payload fairing broke up at T+78 seconds. RSO T+83 seconds.|
|3 November 1966
|CCAFS LC-40||3C-9||Gemini B
|Success||Gemini B was launched on a sub-orbital trajectory|
|18 January 1967
|CCAFS LC-41||3C-13||OPS-9321 (IDCSP)
|28 April 1967
|CCAFS LC-41||3C-10||OPS-6638 (Vela)
|1 July 1967
|CCAFS LC-41||3C-14||OPS-9331 (IDCSP)
|13 June 1968
|CCAFS LC-41||3C-16||OPS-9341 (IDCSP)
|26 September 1968
|9 February 1969
|CCAFS LC-41||3C-17||TACSAT 1 (OPS-0757)||Success|
|23 May 1969
|CCAFS LC-41||3C-15||OPS-6909 (Vela)
|8 April 1970
|CCAFS LC-40||3C-18||OPS-7033 (Vela)
|6 November 1970
|CCAFS LC-40||3C-19||DSP-1 (OPS-5960)||Partial failure||Transtage 3rd burn failure left satellite in unusable lower than planned orbit|
|5 May 1971
|CCAFS LC-40||3C-20||DSP-2 (OPS-3811)||Success|
|3 November 1971
|CCAFS LC-40||3C-21||DSCS-II-1 (OPS-9431)
|1 March 1972
|CCAFS LC-40||3C-22||DSP-3 (OPS-1570)||Success|
|12 June 1973
|CCAFS LC-40||3C-24||DSP-4 (OPS-6157)||Success|
|13 December 1973
|CCAFS LC-40||3C-26||DSCS-II-3 (OPS-9433)
|30 May 1974
|20 May 1975
|CCAFS LC-40||3C-25||DSCS-II-5 (OPS-9433)
|Failure||Transtage inertial measurement unit failure caused it to be stranded in low Earth orbit.|
|14 December 1975
|CCAFS LC-40||3C-29||DSP-5 (OPS-3165)||Success|
|15 March 1976
|26 June 1976
|CCAFS LC-40||3C-28||DSP-6 (OPS-2112)||Success|
|6 February 1977
|CCAFS LC-40||3C-23||DSP-7 (OPS-3151)||Success|
|12 May 1977
|CCAFS LC-40||3C-32||DSCS-II-7 (OPS-9437)
|25 March 1978
|CCAFS LC-40||3C-35||DSCS-II-9 (OPS-9439)
|Failure||Second stage hydraulics pump failure. RSO T+480 seconds.|
|10 June 1978
|CCAFS LC-40||3C-33||OPS-9454 (Vortex)||Success|
|14 December 1978
|CCAFS LC-40||3C-36||DSCS-II-11 (OPS-9441)
|10 June 1979
|CCAFS LC-40||3C-31||DSP-8 (OPS-7484)||Success|
|1 October 1979
|CCAFS LC-40||3C-34||OPS-1948 (Vortex)||Success|
|21 November 1979
|CCAFS LC-40||3C-37||DSCS-II-13 (OPS-9443)
|16 March 1981
|CCAFS LC-40||3C-40||DSP-9 (OPS-7350)||Success|
|31 October 1981
|CCAFS LC-40||3C-39||OPS-4029 (Vortex)||Success|
|6 March 1982
|CCAFS LC-40||3C-38||DSP-10 (OPS-8701)||Success|
- "Archived copy". Archived from the original on 2012-10-25. Retrieved 2013-02-15.CS1 maint: Archived copy as title (link)
- "Titan 3C". Astronautix. Archived from the original on December 25, 2014. Retrieved February 2, 2015.
- "Titan". braeunig.us. Retrieved February 2, 2015.
- Norbert, Bruge. "Titan III/IV Propulsion". B14643.de. Norbert Bruge. Retrieved 20 June 2017.
|Wikimedia Commons has media related to Titan IIIC.|
- Titan III: Research and Development for Today And Tomorrow
- Titan III & variations
- Future Space Booster Requirements - January–February 1969 Air University Review