Launch Pad

Verified Timeline

Lore & Background

In 1961, President Kennedy proposed to Congress the goal of landing a man on the Moon by the end of the decade. Congressional approval led to the launch of the Apollo program, which required a massive expansion of NASA operations, including an expansion of launch operations from the Cape to adjacent Merritt Island to the north and west. NASA began acquisition of land in 1962, taking title to 131 square miles (340 km2) by outright purchase and negotiating with the state of Florida for an additional 87 square miles (230 km2). On July 1, 1962, the site was named the Launch Operations Center. The need for a new launch complex was first considered in 1961. At the time, the highest-numbered launch pad at CCAFS was Launch Complex 37. A proposed Launch Complex 38 had been set aside for the future expansion of the Atlas-Centaur program, but ultimately never built. The new complex was thus designated Launch Complex 39. The method of reaching the Moon had not yet been decided. The two leading alternatives were direct ascent, which launched a single huge rocket; and Earth orbit rendezvous, where two or more launches of smaller rockets would place several parts of the lunar departure spacecraft which would be assembled in orbit. The former would require a huge Nova-class launcher and pads, while the latter would require several rockets to be launched in quick succession. Furthermore, the selection of the actual rockets was still ongoing; NASA was proposing the Nova design while their newly-acquired former Army group in Huntsville Alabama had proposed a series of slightly smaller designs known as Saturn. This complicated the design of the launch complex, as it had to encompass two very different possibilities and rockets. Accordingly, early designs from 1961 show two sets of launch pads. The first was a series of three pads for Saturn along Playalinda Beach, with the southernmost near the current Eddy Creek Boat Launch, and the northernmost around Klondike Beach. Far to the south was a similar set of three pads for Nova, the southernmost just south of the Astronaut Beach House and the northern roughly at the location of the current Pad A. The final selection of lunar orbit rendezvous and the Saturn V led to numerous changes. The Nova pads disappeared, and the three Saturn pads were moved southward. The southernmost was now at the current location of Pad A, while the northernmost was located between Patrol Road, the current boundary road for the LC39 site, and Playlandia Beach Road on the north. At the time, the original three were named from north to south: Pad A through Pad C. The pads were evenly spaced 8,700 feet (2,700 m) apart to avoid damage in the event of an explosion on a pad. In March 1963, plans were formalized to build only two of the three pads; the northernmost, furthest from the VAB, would not be built but reserved for future expansion. As the original Pad A would no longer be built, the naming was changed to run south-to-north, so that the two pads that would be built would be A and B. If the original 39A at the north end were ever built, it would now be known as 39C. Some consideration for C's construction was made: the Crawlerway initially splits off from A toward B running north-northwest, and then bends north toward B a short distance north at Cochran Cove. Continuing straight north-northeast would have led to C after a similar northward bend. The original construction of the Crawlerway included an interchange between B and a short part of the extension northward for C, which remains intact as of 2026, and the traffic-light warning system for the Crawlerway has lights for Pad C. The plans still set aside room for the remaining two pads, now known as D and E, or in other plans, D and D Alternate. Pad D would have been built further north, the same distance and angle as the separation between B and C, producing a line of four equally-spaced pads. This would put it in the bay to the west of Playalinda Beach, close to the original location of the southernmost pad in the original layout. E, or D Alternate, was due west of C, some distance inland along Patrol Road. The crawler way to both locations split off from the path to C, turning due west for a short distance before bending north to reach D, or northwest to E/D Alternate. Had all of these pads been built, C, D and E would have formed a triangle.

In Their Own Story

Months before a launch, the three stages of the Saturn V launch vehicle and the components of the Apollo spacecraft were brought inside the Vehicle Assembly Building (VAB) and assembled, in one of four bays, into a 363-foot (111 m)-tall space vehicle on one of three Mobile Launchers (ML). Each Mobile Launcher consisted of a two-story, 161-by-135-foot (49 by 41 m) launcher platform with four hold-down arms and a 446-foot (136 m) Launch Umbilical Tower (LUT) topped by a crane used to lift the spacecraft elements into position for assembly. The ML and unfueled vehicle together weighed 12,600,000 pounds (5,715 t). The umbilical tower contained two elevators and nine retractable swing arms that were extended to the space vehicle—to provide access to each of the three rocket stages and the spacecraft for people, wiring, and plumbing—while the vehicle was on the launch pad and were swung away from the vehicle at launch. Technicians, engineers, and astronauts used the uppermost Spacecraft Access Arm to access the crew cabin. At the end of the arm, the white room provided an environmentally controlled and protected area for astronauts and their equipment before entering the spacecraft. When the stack integration was completed, the Mobile Launcher was moved atop one of two crawler-transporters, or Missile Crawler Transporter Facilities, 3–4 miles (4.8–6.4 km) to its pad at a speed of 1 mile per hour (1.6 km/h). Each crawler weighed 6,000,000 pounds (2,720 t) and was capable of keeping the space vehicle and its launcher platform level while negotiating the 5 percent grade to the pad. At the pad, the ML was placed on six steel pedestals, plus four additional extensible columns. After the ML was set in place, the crawler-transporter rolled a 410-foot (125 m), 10,490,000-pound (4,760 t) Mobile Service Structure (MSS) into place to provide further access for technicians to perform a detailed checkout of the vehicle, and to provide necessary umbilical connections to the pad. The MSS contained three elevators, two self-propelled platforms, and three fixed platforms. It was rolled back 6,900 feet (2,100 m) to a parking position shortly before launch.

Reader's Guide

SpaceX has leased Launch Complex 39A from NASA since 2014 and has modified the pad to support Falcon 9 and Falcon Heavy launches. NASA began modifying Launch Complex 39B in 2007 to accommodate the now defunct Constellation program, and is currently prepared for the Artemis program, which was first launched in November 2022. A pad to be designated 39C, which would have been a copy of pads 39A and 39B, was originally planned for Apollo but never built. A smaller pad, also designated 39C, was constructed from January to June 2015, to accommodate small-lift launch vehicles. NASA launches from pads 39A and 39B have been supervised from the NASA Launch Control Center, located 3 miles (4.8 km) from the launch pads. LC-39 is one of several launch sites that share the radar and tracking services of the Eastern Test Range.

Did You Know?

• The original construction of the Crawlerway included an interchange between B and a short part of the extension northward for C, which remains intact as of 2026.
• The traffic-light warning system for the Crawlerway has lights for Pad C, even though that pad was not built during Apollo.
• The Mobile Launcher and unfueled vehicle together weighed 12,600,000 pounds (5,715 t).
• Each crawler-transporter weighed 6,000,000 pounds (2,720 t) and moved at 1 mile per hour (1.6 km/h).
• The Mobile Service Structure (MSS) weighed 10,490,000 pounds (4,760 t) and was rolled back 6,900 feet (2,100 m) before launch.