Cape Canaveral Space Launch Complex 41

Space Launch Complex 41 (SLC-41), sometimes referred to as "Slick Forty-one," is one of two launch sites at the Integrate-Transfer-Launch Complex in Cape Canaveral Space Force Station, Florida. Originally built as Launch Complex 41 (LC-41), it and the neighboring Space Launch Complex 40 were designed for the United States Air Force's Titan III rocket program, where it launched the Titan IIIC in the 1960s and the Titan IIIE in the 1970s. In the 1990s, the Air Force and Martin Marietta upgraded the pad for use by the Titan III's successor, the Titan IV.

During the early 2000s, SLC-41 underwent modifications by Lockheed Martin in order to support the launch operations of the Atlas V. It was later transferred to United Launch Alliance (ULA)—a joint venture between Lockheed Martin and Boeing—who continues to use the pad today for launches of the Atlas V and its successor, Vulcan Centaur.

History

Titan IIIC and IIIE (1965–1977)

Launch Complex 41 was originally built as part of the Integrate-Transfer-Launch Complex (ITL), intended to launch Titan III rockets with solid rocket boosters in a method to enable a rapid launch rate. The ITL consisted of a Titan assembly facility at the Vertical Integration Building (demolished in 2006), an SRB attachment facility at the Solid Motor Assembly Building (now used by SpaceX to process Falcon 9 payloads), and two pads at Launch Complex 40 (LC-40, now SLC-40) and LC-41, all connected by the first rail line at the Cape. The facilities were completed in 1964, and the first launch from LC-41 was of a Titan IIIC carrying four separate payloads on December 21, 1965.

Throughout the remainder of the 1960s, LC-41 was used to launch 10 Titan IIICs, the entirety of them being military payloads such as Vela nuclear detection satellites and Lincoln Experimental Satellites. The last Titan IIIC launch from LC-41 took place in May 1969, launching Vela satellites OPS-6909 and OPS-6911, the later of which would detect a double flash in the southern Indian Ocean and instigate the Vela incident ten years later. All remaining launches of the rocket were made from LC-40.

In the early 1970s, LC-41 underwent a modification to launch the Titan IIIE, which replaced the Transtage upper stage of the IIIC with a Centaur. With the exception of its inaugural flight in February 1974, every launch from the pad in this era contained a NASA payload. Those satellites were the two Helios probes sent to study the Sun (setting a proximity record only broken by the Parker Solar Probe), the two Viking probes sent to orbit and land on Mars, and the two Voyager spacecraft that flew by Jupiter, Saturn, Uranus, and Neptune. The Titan III facility at Complex 41 was deactivated in late 1977, following September's launch of Voyager 1.

Titan IV (1989–1999)

In 1986, the existing mobile service tower and umbilical tower at LC-41 were both stripped down to their main structural components as part of a renovation conducted by Titan manufacturer Martin Marietta. This was done as part of their "tear-out and refurbish" contracts, which modified and prepared the ITL for its new rocket configuration: LC-40 would get converted to use the civilian-based Commercial Titan III, while LC-41 would be used for the military-focused Titan IV. Additionally, Titan IV processing would go through the newly-constructed Solid Motor Assembly Readiness Facility (now used by ULA in the assembly of Vulcan Centaur) prior to launch. The maiden flight of the Titan IV occurred on June 14, 1989, carrying USA-39 for the United States Air Force. Similarly to most other Titan launches, all 10 launches of the Titan IV from LC-41 were classified military payloads, most going into geostationary transfer orbit.

The Titan family of the 1980s and 1990s was marred by its price in the eyes of commercial customers, who instead opted to use cheaper launch vehicles like Delta II and Ariane 4. Following Lockheed's merger with Martin Marietta in 1995, Lockheed Martin eventually decided to begin the process of retiring the Titan program in favor of their cheaper Atlas line. With any remaining Titan IV launches to be made from LC-40, the last Titan launch from LC-41 was on April 9, 1999, when a Titan IVB launched the USA-142 early warning satellite. The IUS upper stage failed to separate, leaving the payload stranded in a useless GTO orbit.

Atlas V and Vulcan Centaur (2002–present)

After the last Titan launch, LC-41 was renovated by Lockheed Martin and the Air Force to support the Atlas V as part of the Evolved Expendable Launch Vehicle program, getting rechristened as SLC-41 in the process. The old launch tower and mobile service structure were demolished, while the new Vertical Integration Facility was built for the assembly of the new launch vehicle. Additionally, the rail lines going towards the pad were renovated to support the assembly and transportation of the Atlas V and it's mobile launcher platform for liftoff. SLC-41 was the site of the first-ever Atlas V launch on August 21, 2002, lifting Hot Bird 6, a Eutelsat geostationary communications spacecraft built around a Spacebus 3000B3 bus.

Over the years of the Atlas V era, SLC-41 was used to launch various noteworthy payloads for various agencies such as NASA and the Air Force. These include the Mars Reconnaissance Orbiter in August 2005, the New Horizons spacecraft to Pluto in January 2006, the Juno mission to Jupiter in August 2011, and two of the Mars rover missions; Mars Science Laboratory in November 2011, and Mars 2020 in July 2020. Other notable payloads to be mentioned are various launches of the Boeing X-37B for the Air Force throughout the 2010s, and a couple of Cyngus flights to the International Space Station in 2015 and 2016 following the failure of Cygnus Orb 3.

In 2005, it was announced that a joint venture would form between Lockheed Martin and Boeing that would combine Atlas V operations at SLC-41 with Delta II and Delta IV operations at SLC-17 and SLC-37 respectively, following issues with profit abounding with competition between the two. This transfer in operation was made official in December 2006, with the formation of United Launch Alliance. The first launch from SLC-41 under ULA came in March 2007 with a variety of Department of Defense payloads lifting off from an Atlas V.

In 2011, the idea of rebuilding a launch tower at SLC-41 began to get proposed following Sierra Nevada Corporation and Boeing's decisions to have the Atlas V launch their respective Dream Chaser and CST-100 Starliner spacecraft into orbit. Proposals turned into plans in 2014, following Boeing's winning of a contract as part of NASA's Commercial Crew Program to launch astronauts to the ISS. Pad modifications at SLC-41 began in September 2015 to support human spaceflight to support Starliner, including the addition of a launch service tower to provide access to the capsule for "pre-launch processing, crew access, and safety egress systems should the need to evacuate Starliner on the pad occur". The first launch utilizing the newly-built launch tower came on December 20, 2019 with the launch of the Boeing Orbital Flight Test. This was followed up with the first crewed launch to be made from SLC-41, which occurred on June 5, 2024 with the Boeing Crew Flight Test and carried astronauts Barry Wilmore and Sunita Williams into orbit. This was the first crewed launch from Cape Canaveral Space Force Station since Apollo 7 in 1968 and made SLC-41 the seventh pad in the Cape Canaveral area to launch astronauts into space.

During the late 2010s and the early 2020s, SLC-41, the VIF, and the SMARF (which was renamed to the Spaceflight Processing Operations Center in 2019) underwent minor modifications to support Vulcan Centaur, the successor to the Atlas V and Delta IV. This was in part due to the Atlas V using the Russian-built RD-180 as its first stage engine, which drew concern among Congress following the 2014 annexation of Crimea and the Russian invasion of Ukraine in 2022. As the Atlas V still had numerous pending launches (mainly for Starliner and Kuiper satellites as payloads), SLC-41's modifications were made to allow both rockets to take off from the pad, rather than a more traditional renovation like what was seen at Vandenberg's SLC-3E. The first Vulcan launch to be made from the pad occurred on January 8, 2024, carrying Peregine Mission One to the Moon as part of NASA's Commercial Lunar Payload Services.

To support a higher launch cadence, particularly for Amazon’s Project Kuiper constellation, ULA is expanding its infrastructure at SLC-41. The company acquired the former Solid Motor Assembly and Readiness Facility (SMARF), originally built for the Titan IVB program, and repurposed it as the Spaceflight Processing Operations Center (SPOC). Initially used as a warehouse for construction of two mobile launcher platforms for Vulcan, the SPOC is now being converted into a second integration facility, designated VIF-A (Amazon Vertical Integration Facility). Planned upgrades include raising the roof by 45 feet, adding storage space for a mobile launcher platform, and creating an offline vertical integration (OVI) cell to allow parallel processing of the Centaur V upper stage and Vulcan booster prior to stacking. Once VIF-A is operational, the existing VIF will be redesignated VIF-G (Government Vertical Integration Facility) and primarily support national security launches.

Launch history

Statistics

• Titan III-C
• Titan IIIE
• Titan IV
• Atlas V
• Vulcan Centaur

Titan III and IV

All launches operated by the United States Air Force.

Pre-Starliner Atlas V

All launches from 2002 to 2006 operated by Lockheed Martin. All launches since 2007 operated by United Launch Alliance.

Starliner-era Atlas V and Vulcan Centaur

All launches operated by United Launch Alliance.

Upcoming launches

Gallery

• A Titan IIIE launching Voyager 2 from LC-41 in 1977.
• A Titan IV on LC-41 in 1996. The steel towers visible at the left and right are part of the lightning protection system.
• SLC-41 in its early Atlas V years, carrying New Horizons as its payload in 2006.
• An Atlas V launching from the pad, with the crew access tower (left) complete.
• A Vulcan Centaur Launches from SLC-41 in October 2024.

See also

• List of Cape Canaveral and Merritt Island launch sites
• Cape Canaveral Space Launch Complex 40

Notes

External links

2022-11-26 at the Wayback Machine