Thiokol

A Trident II (D-5) FBM launches and fires its Thiokol solid rocket first stage

Thiokol (variously Thiokol Chemical Company, Morton-Thiokol Inc., Cordant Technologies Inc., Thiokol Propulsion, ATK Thiokol; currently ATK Launch Systems Group) is a U.S. corporation concerned initially with rubber and related chemicals, and later with rocket and missile propulsion systems. Its name is a portmanteau of the Greek words for sulfur (Θειο "theio") and glue (κολλα "kolla"), an allusion to the company's initial product.

The Thiokol Chemical Company was founded in 1929. Its initial business was a range of synthetic rubber and polymer sealants, and Thiokol was a major supplier of liquid polymer sealants during World War II. When scientists at the Jet Propulsion Laboratory discovered Thiokol's polymers made ideal rocket fuels, Thiokol moved into the new field, opening laboratories at Elkton, Maryland, and later production facilities at Elkton and at Redstone Arsenal in Huntsville, Alabama. Huntsville produced the XM33 Pollux, TX-18 Falcon, and TX-135 Nike-Zeus systems. It closed in 1996. In the mid 1950s the company bought extensive lands in Utah for its rocket test range, and continues to have major operations in the state, at Magna, Promontory (home of the Space Shuttle's SRB), and its current headquarters at Brigham City. As of 2005 the company employs over 4,000 people worldwide and records annual sales of around $ 840 million.

Company history

• 1929: Thiokol Chemical Company founded.
• 1949: Thiokol produce the TX-18 Falcon missile, the world's first solid-fueled missile system.
• 1957: In anticipation of the forthcoming Minuteman contract, the company builds its plant at Brigham City, Utah.
• 1957: Thiokol Huntsville builds XM33 Pollux missile
• 1958: Merger with Reaction Motors Inc. (RMI), makers of liquid propellant rocket motor systems.
• 1958: Thiokol awarded contract to build the TU-122 rocket motor for the first stage of the LGM-30 Minuteman ICBM system.
• 1959: Thiokol Huntsville produces CASTOR strap-on booster rocket, used on the Atlas rocket.
• 1974: Thiokol wins the contract to build the solid rocket booster (SRB) for the Space Shuttle
• 1978: The company sells its ski lift division to CTEC and its snow equipment division to Logan Manufacturing Company (LMC), owned by John DeLorean.
• 1980: Acquires Carlisle Chemical Company of Cincinnati, Ohio.
• 1982: Thiokol merges with Morton-Norwich products (owners of the Morton Salt concern, the Simoniz automotive products brand, and various chemical concerns). The merged company is called Morton Thiokol Incorporated (MTI).
• 1986: An O-ring fault in an MTI SRB destroys space shuttle Challenger in flight
• 1989: Morton Thiokol splits, with most of the chemical concern going with Morton. The propulsion systems division becomes Thiokol Inc.
• 1998: Thiokol changes name to Cordant Technologies.
• 2000: Thiokol merges with two divisions of Alcoa and with Howmet Castings and Huck Fasteners to become AIC Group (Alcoa Industrial Components).
• 2001: Alliant Techsystems (ATK) Inc. (a company formed when Honeywell spun off its defense division) spends $2.9 billion buying Thiokol and related businesses from AIC/Alcoa. ATK built the third stage of the Trident missile and had earlier bought Hercules Aerospace Co., builder of the second stage. With the purchase of Thiokol, who make the missile's first stage, ATK controls the lion's share of the US solid-rocket market.
• 2005, Thiokol wins the contract to produce the Ares I launch vehicle first stage for NASA's Project Constellation.
• 2006, Alliant Techsystems (ATK) Inc. renamed ATK-Thiokol to ATK Launch Systems Group.

Products

Thiokol gas generators were used in the airbags on Mars Pathfinder. The top photo shows a complete airbag assembly under test, the bottom shows the three titanium Thiokol gas generators used to inflate the airbags.

Products made by the aerospace divisions of RMI and Thiokol include motors used in Subroc, the Pershing missile, the Peacekeeper missile, Poseidon missile, Minuteman missile, and the Trident I and Trident II missiles. Thiokol produces powerplants for numerous U.S. military missile systems, including AIM-9 Sidewinder, AGM-88 HARM, AGM-65 Maverick, AGM-69 SRAM, and AIR-2 Genie.

Model 601 U.S.A.F. Thiokol Snowcat

Thiokol also produced a variety of liquid and solid rocket motors for the US space program, including deorbit motors for the Mercury and Gemini programs, rocket stages and separation rocket motors for the Apollo program, motors for the Pioneer, Surveyor, Viking, Voyager, and Magellan missions, updated CASTOR boosters for the Delta rocket, and the Space Shuttle Solid Rocket Booster. Reaction Motors powerplants propelled the X-1 and X-15 aircraft, and later Thiokol technologies were also used in the private Tier One manned spaceplane. On March 1, 2006, NASA announced that Thiokol will be the prime contractor for the new Crew Launch Vehicle (CLV), to be known as the Ares I, which will put the Orion spacecraft (formerly known as the "Crew Exploration Vehicle") into low earth orbit, along with the five-segment SRBs for the heavy-lift Cargo Launch Vehicle (CaLV), known as the Ares V.

Trail Grooming with a Thiokol IMP Snowcat in Wyoming

In addition to ski lifts, Thiokol produced a range of equipment for ski resorts including snowcats and snow grooming vehicles. These businesses were spun off in 1978 when the company restructured itself to concentrate on its rocket products and related technologies. John Z. DeLorean purchased the Thiokol snowcat operation and renamed it DMC. DMC continued to manufacture snowcats until 1988 when the company was renamed LMC. Logan Machine Company continued making snowcats for 12 more years but ceased operations in 2000. Thiokol produced a wide range of snowcats with a wide range of capabilities for a wide range of duties. Thiokol produced several utility based vehicles that were based on their snowcat tracked vehicle designs in addition to larger snow grooming machine that were suitable for use on steep ski-slopes. Thiokol machines were used in ski resorts, operated by the U.S.A.F. in Alaska and other northern regions, and are now popular with private owners as dependable snowcats and for all terrain transport.

Amphibious Thiokol Swamp Spryte All Terrain Vehicle

Thiokol pioneered the short-burn rocket motors used in aircraft ejector seats. The company also produced a number of the earliest practical airbag systems, building the high-speed sodium azide exothermic gas generators used to inflate the bags. Thiokol bags were first used in U.S. military aircraft, before being adapted to space exploration (Mars Pathfinder bounced down on Mars on Thiokol airbags) and automotive airbags. Thiokol's generators form the core of more than 60% of airbags sold worldwide, in everything from the Lincoln Town Car to the Mazda Miata.

Space Shuttle Challenger Disaster

The Space Shuttle Challenger accident occurred on the morning of January 28 1986, at 11:39 EST, when Space Shuttle Challenger disintegrated 73 seconds into its flight

Later in 1986, the Rogers Commission and the United States House Committee on Science found that the Challenger accident was caused by a failure in the O-rings sealing a joint on the right solid rocket booster, which allowed pressurized hot gasses and eventually flame to "blow by" the O-ring and make contact with the adjacent external tank, causing structural failure. The failure of the O-rings was attributed to a faulty design, whose performance could be too easily compromised by factors including the low temperature on the day of launch.

The Viton O-rings that failed were manufactured by Morton-Thiokol.

However, NASA's specification did not require them to work properly at such cold temperatures. Since the launch site was in Florida, the design specification for the Solid Rocket Boosters (SRBs) was 40 degrees Fahrenheit minimum; well above the freezing point. Shortly before launch, the temperature of the joint near the area that failed was measured at 26 degrees F, due to overnight temperatures in the 20s. Under conditions similar to those in the joint O-rings, Viton is known to recover from compression roughly twice as fast at 45 degrees than at 25. The House committee's report stated that ice in the joint prior to firing may have interfered with O-ring sealing as well.

See Also

• Antarctic snow cruiser
• Logan Machine Company
• Sno-Cat
• Snow coach
• Snowcat
• Snow grooming

External Links

• ATK Launch Systems Group homepage
• History of Reaction Motors Inc.
• History of Thiokol
• Photographs of Thiokol snowcat and snow-grooming equipment
• Thiokol's connection to Snowcats and John DeLorean