The iconic launch pads, Pads 39A and 39B at Kennedy Space Center’ s Launch Complex 39, have been the starting point for many space flights including the first manned lunar landing. The original design for Launch Complex 39 called for three to five launch pads, designated 39A – 39E, that would have been spaced approximately 1.6 miles apart to protect them from damage if any mishaps occurred at an adjacent pad. Also part of Launch Complex 39 is the Vehicle Assembly Building, or VAB. Towering more than 500 feet, it can be seen easily from miles away. The Launch Control Center, or LCC, where all the launch controllers, support personnel, and equipment required to safely launch a vehicle from either of the launch pads is also a part of the large complex.
Pad 39A from sand to Apollo
Pad 39A was originally designated to be Pad 39C in the complex’ s original plan, however it became 39A when plans to build the three additional pads were scrapped in 1963. Launch Complex 39’ s A pad was completed first. Construction began in November of 1963 and was completed in early September 1965. Built on around a quarter square mile of land, the launch site is an eight sided polygon and measures 3,000 feet across. The pad itself is 390 feet by 325 feet and is constructed of reinforced concrete. The hardstand stands 48 feet above sea level. To get from sea level up to the hard stand, a five-percent sloped ramp was constructed. Which raises the question,“ Why build up and not down to avoid having to have a ramp up to the pad?”. The answer is simple, the pads are located in Florida just a quarter mile away from the Atlantic Ocean, and digging down just a few feet you will encounter water. So to protect all the equipment and facilities that are under the pad, the decision to build above ground was made.
For Apollo, the pad would be a clean pad, no structure, towers, or other support equipment was located on top of the pad. All these items would be brought with the vehicle. The vehicle was assembled on a massive platform known as a Mobile Launcher. On the Mobile Launcher was a Launch Umbilical Tower( LUT) and a mobile service structure which allowed for crew access, all the umbilical connections for the rocket, elevators, service platforms, everything you needed to get the vehicle ready for launch on the pad. The Mobile Launcher was transported by a new vehicle, called the Crawler, from the Vehicle Assembly Building out to the pad. The Mobile launcher would be lowered onto pedestals located atop the hardstand.
Without the Mobile Launcher at the pad, from the outside mostly what you see at Pad 39A is the pad itself, however much more lies beneath the exterior. A two-story pad terminal connection room which houses all of the electronic equipment that would connect the Launch Control Center with the Mobile Launcher when it’ s on the pad, is located on the western side of the pad. Also on the same side is the environmental control systems room which supports the air conditioning and water systems. Beneath the east side of the pad is the high-pressure-gas storage facility, where nitrogen and helium gases piped from the converter-compressor
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