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Space Shuttle Crawler

Space Shuttle Crawler


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Launching To Space at a Crawl

How NASA&rsquos massive crawler-transporters get millions of pounds of rocket to the launchpad one inch at a time.

Welcome to Apollo Week, celebrating 50 years since the Apollo 11 mission, explaining what it means today, and exploring how its legacy will shape the future of space exploration.

Reaching space takes a lot of gas, and gas is heavy.

The total liftoff weight of the now defunct Space Shuttle system was 4.5 million pounds. The Shuttle&rsquos boosters, external tank, and the fuel made up most of that weight. Add in the mobile launch platform (MLP) and the entire assembly weighed 12.6 million pounds.

So how do you get nearly 13 million pounds to the launch pad? Build a 6.3 million pound transporter the size of a baseball infield.

NASA&rsquos two crawler transporters, named simply CT-1 and CT-2, are historic machines for a number of reasons. They&rsquove carried everything from the first Saturn V rocket and capsule for the 1967 Apollo 4 mission to space shuttle Atlantis for its last shuttle mission (STS-135) in 2011. And their biggest challenge lies ahead as the crawler-transporters are outfitted to carry the Space Launch System (SLS) rocket, a spacecraft that could one day help put humans on Mars.

Strange Beginnings

In the early 60s, NASA considered several methods for transporting spacecraft including rail line and canal-and-barge schemes. But NASA engineers were inspired by mining operations that used mammoth equipment like the Bucyrus-Erie &ldquoBig Hog&rdquo strip mining shovel. Big Hog sat atop independent diesel-powered tracks, free of ties to rail or water pathways. Ultimately, Bucyrus rival, Marion Shovel Company of Marion, Ohio would build the crawlers in 1965 using the tracked design.

But 53 years ago, the crawler-transporter was built for to ferry the Apollo spacecraft between the Kennedy Space Center&rsquos Vehicle Assembly Building (VAB) and launch pads 39A and 39B, 3.4 and 4.2 miles away respectively.

The trip from the VAB to the launch pad takes about six hours, and over the years the crawler transporters have made it well over 300 times carrying everything from the first Saturn V rocket and capsule for the 1967 Apollo 4 mission to space shuttle Atlantis for the last shuttle mission (STS-135) in 2011. NASA estimates that each crawler has racked up over 2,200 miles on the gravel paths called &ldquocrawlerways.&rdquo

The crawlers are among the largest self-propelled land vehicles ever produced, and their mission begins when one leaves the crawler yard with a crew of 15 to 20 engineers and technicians. It heads for an MLP, lifts it up and carries it into the VAB where it lowers the MLP onto high pedestals.

Once a spacecraft and boosters have been assembled on the MLP, the crawler slides beneath the MLP and secures the entire load to its deck. Then it sets off for the launch site by steadying the top-heavy load with a laser guidance system and giant jacking, equalization, and leveling cylinders at each corner.

With the crawlerways lined with &ldquoAlabama river rock&rdquo from an Alabama quarry, crawler-transports move as fast as 1 mph with works spraying the rocks with water to avoid excess dust. Although a lumbering mammoth, the crawler-transporter can move with extreme precision, traveling as little as one-eighth of an inch, as reported by Road & Track magazine, which &ldquoroad tested&rdquo the crawlers in the 1970s.

Because each launch site is built atop a sloping pyramid of land, the crawler uses its JELs to keep the platform level all the way to the top where it sets the platform in place. It then parks far away from the pad to avoid damage during the launch. Once safely spacebound, the crawler retrieves the MLP and returns to the crawler yard.

The Original Hybrid

NASA&rsquos Crawler Project Manager, John Giles, calls the transporters the &ldquooriginal&rdquo hybrid vehicles. &ldquoThat&rsquos because we use engines to generate electricity to propel us via electric motors,&rdquo he told Popular Mechanics.

It&rsquos the same basic idea Chevy uses on its Volt hybrid cars. The crawler employs four V16 diesel engines&mdashtwo in front, two in back. At each end one produces DC current sent to eight electric traction motors powering two trucks. The other diesel produces AC current for lights, computers, and power to the payload. The trucks contain huge bearings supporting two massive belt tracks each. Each belt contains 57 tread belt &ldquoshoes,&rdquo and each shoe is 7.5 feet long, 1.5 feet wide, and weighs 2,100 pounds.

With eight one-ton shoes simultaneously slapping the earth, &ldquoyou get a low frequency vibration which you feel when riding on the crawler. It&rsquos a lot like being on a ship,&rdquo Giles says.

At the end of the Shuttle program in 2012 NASA did an extensive study of alternatives to the aging crawler-transporters but concluded they were still the most efficient way to get loads to the pad, and the Chinese space program agreed. They too use transporters at their Wenchang Spacecraft Launch Site on Hainan Island, but their wheels mean they can only carry about one-third as much as the NASA&rsquos crawler-transports.

Crawling Into the Future

With the U.S.&rsquos next heavy-launch rocket the SLS, CT-2 is getting upgraded so it can carry an 18 million-pound load. New JELs, brakes, roller bearings, 16 rebuilt gearboxes and a new Cummins V16 twin-turbo diesel have been added. CT-1 will get a less heavy-duty refurbishment and will still be used for non-SLS loads.

The two crawlers originally cost a total of $14 million, not bad when stretched over 50-plus years with plans to serve at least another 20 years.

If they&rsquore refurbished again, NASA engineers say they&rsquoll need to reinforce a roof beam in one of the crawlers. There, the Marion Shovel engineers who built it signed their names and drew a 1965 Mustang, knighting the CTs as the most ultimate muscle cars on Earth.

This story was originally published on February 14, 2018. It's been updated for the 50th anniversary of Apollo 11.


Crawler - Transporter

Traveling 1 mph, the crawler carries the launch vehicle with its mobile launcher platform to the launch pad using a laser guidance system and lowers them both onto the pad pedestals. After the launch, the crawler re-lifts the mobile launcher and returns it. Each transporter travels on eight tracked tread belts containing 57 tread belt "shoes."

One crawler houses 16 traction motors, two AC and two DC generators, and two control cabs that drive the vehicle forward and backward. The jacking, equalizing, and leveling (JEL) system keeps the upper deck and pickup points level at all times, even when traveling at an incline, to prevent the payload from toppling.

NASA's Ground System Development and Operations Program (GSDO) has been refurbishing the crawlers since the last space shuttle launch in 2011. CT-1 is being strengthened to carry commercially operated launch vehicles, while CT-2 is being modified to support NASA's Space Launch System (SLS) and the Orion spacecraft. The JEL system is being upgraded to increase how much weight the crawlers can carry from the previous 12 million pounds to the needed 18 million pounds.

Traveling 1 mph, the crawler carries the launch vehicle with its mobile launcher platform to the launch pad using a laser guidance system and lowers them both onto the pad pedestals. After the launch, the crawler re-lifts the mobile launcher and returns it. Each transporter travels on eight tracked tread belts containing 57 tread belt "shoes."

One crawler houses 16 traction motors, two AC and two DC generators, and two control cabs that drive the vehicle forward and backward. The jacking, equalizing, and leveling (JEL) system keeps the upper deck and pickup points level at all times, even when traveling at an incline, to prevent the payload from toppling.

NASA's Ground System Development and Operations Program (GSDO) has been refurbishing the crawlers since the last space shuttle launch in 2011. CT-1 is being strengthened to carry commercially operated launch vehicles, while CT-2 is being modified to support NASA's Space Launch System (SLS) and the Orion spacecraft.

The JEL system is being upgraded to increase how much weight the crawlers can carry from the previous 12 million pounds to the needed 18 million pounds.

Topics. This historical marker is listed in these topic lists: Air & Space &bull Exploration &bull Man-Made Features. A significant historical year for this entry is 1965.

Location. 36° 26.21′ N, 89° 4.252′ W. Marker is in Union City, Tennessee, in Obion County. Marker is on Graham Drive. Inside Discover Park America in Exploration area left side park toward the back. Touch for map. Marker is at or near this postal address: 210-260 Graham Dr, Union City TN 38261, United States of America. Touch for directions.

Other nearby markers. At least 8 other markers are within walking distance of this marker. YP-84A Thunderjet (here, next to this marker) Stem Landing (here, next to this marker) F11F-1 Tiger (a few steps from this marker) UH-1B Iroquois (a few steps from this marker) Geodesic Dome (a few steps from this marker) Titan 1 Launch Complex (a few steps from this marker) Engineering the Dome (a few steps from this marker) LR91-AJ -3 Engine (within shouting distance of this marker). Touch for a list and map of all markers in Union City.

Also see . . . NASA's Giant Crawlers turn 50 Years Old, Pivot Future Exploration. NASA's crawler-transporters, two of the largest vehicles ever built, have carried NASA rockets and spacecraft to the launch pad for the last 50 years. They will continue


According to https://www.popularmechanics.com/space/rockets/a15777930/launching-to-space-at-a-crawl/
it is to reduce dust created as the crawler crushes some of the "Alabama River Rock".

Photo showing the crushed rock behind the crawler. (Source - Organic Marble)

Addendum:
According to the documentary 'When We Were Apollo', the gravel was not part of the original design, but added as a sacrificial bearing surface to stop damage that was occurring to the internal bearings. (Which raises the question: is it raked after use, and periodically replaced?)

2.7 million kgs) $endgroup$ &ndash Kevin Jun 26 '19 at 18:01

I can tell you why as I’ve been involved in the project for years. When the crawler rolls over that river rock it crushes it and the resulting crushing motion releases silica dust in every form (total, inhaleable, and most importantly, respirable). When the crawler rolls out, a team of crawler technicians are escorting it both on the ground and on the crawler. Studies have shown that these workers past and present have suffered respiratory issues as a result of this silica. As a result, the watering of the river rocks prior to the crawler crushing them, is an attempt to reduce this silica dust release.


Crawler - Transporter

KSC has 2 crawler-transporters. Each vehicle consists of four double-tracked crawlers, each 3 meters (10 ft) high and 12 meters (41 ft) long. Each of the 8 tracks on a vehicle contains 57 shoes per track and each tread shoe weighs about .9 metric tons (one ton). Click here to see the crawler moving a shuttle .

The Crawler/Transporter is powered by 16 traction motors powered by four 1,000 kw generators, driven by two 2,750hp diesel engines. Two 750 kw generators, drived by two 1,065 hp diesel engines are used for jacking, steering, lighting, and ventilating. Two 150 kw generators are also used for MLP power.

When they were built, the KSC crawlers were the largest tracked vehicles ever made. (Surpassed by the Bagger 288 German excavator ). They move the Mobile Launcher Platform into the Vehicle Assembly Building and then to the Launch Pad with an assembled space vehicle. Maximum speed is 1.6km (one mile) per hour loaded, about 3.2 km (2 miles) per hour unloaded. Launch Pad to VAB trip time with the Mobile Launch Platform is about 5 hours. The crawler burns 568 liters (150 gallons) of diesel oil per mile.

The top of the orbiter is kept vertical within plus or minus 10 minutes of arc, about the diameter of a basketball during the journey. Leveling systems within the crawler keeps the platform level while negotiating the 5% ramp leading up to the pad surface.

The height of the crawler is 6 meters (20ft) to 8 meters (26 feet) adjustable. The top deck is flat and square, about the size of a baseball infield, 27 meters (90 feet) on a side. Two operator control cabs, one at each end of the chassis, are used to control all crawler systems.

KSC's two crawler-transporters have accumulated 1,243 miles since 1977. Including the Apollo years, the transporters have racked up 2,526 miles, about the same distance as a one-way trip from KSC to Los Angeles by interstate highway or a round trip between KSC and New York City.


Space Shuttle Crawler - HISTORY

NASA CENTERS AND RESPONSIBILITIES

NASA's John F. Kennedy Space Center.in Florida is responsible for all launch, landing and turnaround operations for STS missions requiring equatorial orbits.

The Lyndon B. Johnson Space Center in Houston, Texas, is responsible for the integration of the complete space shuttle vehicle and is the central control point for space shuttle missions.

NASA's George C. Marshall Space Flight Center in Huntsville, Ala., is responsible for the space shuttle main engines, external tanks and solid rocket boosters.

NASA's Goddard Space Flight Center in Greenbelt, Md., operates a worldwide tracking station network.

The United States Air Force operates the space shuttle launch and landing facility at Vandenberg Air Force Base in California for STS missions requiring polar orbit.

JOHN F. Kennedy Space Center.p> The Kennedy Space Center.has primary responsibility for prelaunch checkout, launch, ground turnaround operations and support operations for the space shuttle and its payloads. Space shuttle payloads are processed in a number of facilities at KSC and the nearby Cape Canaveral Air Force Station. Payloads are installed in the space shuttle orbiter horizontally in the Orbiter Processing Facility or vertically at the launch pad. Payloads to be installed horizontally in the orbiter at the Orbiter Processing Facility are verified in the Operations and Checkout Building at KSC. Payloads installed vertically in the orbiter at the launch pad consist primarily of automated spacecraft involving upper stages and their payloads (e.g., satellites).

KSC's responsibility extends to ground operations management systems and plans, processing schedules, facility design and logistics in support of the space shuttle system and payloads.

The center established the requirements for facilities and ground operations support at Vandenberg Air Force Base and designated contingency landing sites. KSC also supports the Department of Defense for ground operations at Vandenberg Air Force Base and maintains NASA facilities and ground support equipment there.

The launch facilities-Launch Complexes 39-A and 39-B-and the technical support base of the center's industrial area were carved out of virgin savanna and marsh in the early 1960s for the Apollo program.

In reshaping KSC for the space shuttle, planners took maximum advantage of existing buildings and structures from the Apollo program that could be modified, scheduling new ones only when a unique requirement existed. New facilities that have been built to support space shuttle operations are the shuttle landing facility (runway) the Orbiter Processing Facility and recently the Orbiter Modification and Refurbishment Facility, Tile Processing Facility, Solid Rocket Booster Storage and Processing Facility, Shuttle Logistics Building and Solid Rocket Booster Assembly and Refurbishment Facility.

KSC is located at 28.5 degrees north latitude and 80.5 degrees west longitude. It encompasses approximately 140,000 acres of land and water. This area, with the adjoining bodies of water, is sufficient to afford adequate safety to the surrounding communities during space shuttle launch and landing activities.

The shuttle processing contractor performs all launch processing and turnaround activities at the Kennedy Space Center.and Vandenberg Air Force Base. Lockheed Space Operations Company, Titusville, Fla., was awarded the contract in 1983 to perform space shuttle launch processing operations previously carried out by more than a dozen separate contractors, which included the major hardware manufacturers.

The SPC is responsible for processing individual vehicle elements, integrating those elements in preparation for launch, performing cargo integration and validation activities with the orbiter, operating and maintaining assigned facilities and required support equipment and performing those tasks necessary to accomplish launch and postlaunch activities successfully.

    After they arrive at the Kennedy Space Center. space shuttle orbiters are processed between missions in a structure analogous to a sophisticated hangar-the Orbiter Processing Facility. The OPF is capable of handling two orbiters in parallel. It is located near the west side of the Vehicle Assembly Building in order to minimize orbiter towing distance as the processing flow continues.

The OPF has two identical bays that are each 197 feet long, 150 feet wide and 95 feet high have an area of 29,000 square feet and are equipped with two 30-ton bridge cranes with a hook height of approximately 66 feet. A low bay separating the two bays is 233 feet long, 97 feet wide and 24.6 feet high. A 10,000-square- foot annex is located on the north side of the facility. Another new 34,000-square- foot, three-story annex will provide additional office space.

In the high bays, a trench system under the floor contains electrical, electronic, communication, instrumentation and control cabling hydraulic supply and return plumbing gaseous nitrogen, oxygen and helium plumbing and compressed air distribution plumbing. Gaseous nitrogen, helium and compressed air are supplied by the systems in the Vehicle Assembly Building. All of these systems are used to support processing and maintenance of the orbiters during ground turnaround operations.

The two high bays have an emergency exhaust system in case of hypergolic spills. The low bay houses areas for electronic equipment, a launch processing system interface, mechanical and electrical equipment shops and thermal protection system repair. The low bay also includes provisions for a communications room, offices and supervisory control rooms.

Some orbiter processing activities performed in the OPF are hazardous, and personnel who are directly involved are required to wear protective suits, called self-contained atmosphere protective ensembles. The use of SCAPE suits is required during operations involving the reaction control system, orbital maneuvering system, and auxiliary power units and their hypergolic propellants.

Fire protection systems are provided in all three bays.

Two large rolling bridges span the main access bridge to provide complete access to installed payloads, radiators, internal areas of the payload bay and external areas of the payload bay doors. Each of the rolling bridges supports two independently movable trucks with a personnel bucket at the bottom of each vertically telescoping arm. The buckets are manually rotatable around a full circle. The bridges, trucks and telescoping arms are electrically powered and controlled from the buckets or the catwalk.

Flip-up work platforms parallel the payload bay area to provide access to radiators, the inside payload bay doors, payload bay door hinges and trunnion points.

Other platforms provide access to other orbiter elements.

The hinges of the payload bay doors are not designed to support the weight of the doors while they are open horizontally in the Earth's 1-g environment. A counterweight zero-gravity device supports the weight of the doors while they are open for processing in the OPF.

The orbiter processing flow begins when an orbiter lands at the shuttle landing facility after a mission in space or a ferry flight aboard the shuttle carrier aircraft. In either case, the orbiter is towed to the OPF within hours of its arrival.

Access to the crew module is established soon after the orbiter lands. Flight crew equipment is removed at that time, along with any middeck experiments flown on the mission.

Processing starts when the orbiter is jacked up off its landing gear and leveled, workstands are moved into position and preparations begin to gain access to various orbiter areas. The orbiter is connected to ground power, facility ground coolant, purge air and the LPS.

Initial safing operations include hooking up purge, vent and drain lines. Any unexpended pyrotechnics (ordnance devices), such as those used for backup landing gear deployment, are disabled and safed. Purging and deservicing of the orbiter's orbital maneuvering system/reaction control system, forward reaction control system and auxiliary power unit hypergolic systems are initiated.

Some of these are hazardous operations, which require that the OPF be cleared of all non-essential personnel. Hypergolic deservicing operations require that personnel wear SCAPE suits.

The hypergolic lines of the OMS/RCS and forward RCS are drained of trapped propellants and their interface connections are purged. Residual hypergolic fuels in onboard tanks are not usually drained.

When required, the OMS/RCS pods and the forward RCS are removed and taken to the Hypergolic Maintenance and Checkout Facility in the industrial area for maintenance.

After the orbiter has been rolled into the OPF, a purge of the space shuttle main engines is initiated to remove moisture produced as a by-product of the combustion of liquid oxygen and liquid hydrogen.

Fuel cell cryogenic tanks are drained of residual reactants and rendered inert using gaseous nitrogen in the oxygen system and gaseous helium in the hydrogen system. High-pressure gases are vented from the environmental control and life support system.

Before postflight deservicing can continue beyond initial safing operations, certain vehicle systems must be mechanically secured and personnel access installed.

Space shuttle main engine gimbal locks and engine covers are installed, and engine heat shields are removed. Aft access doors are removed, and workstands are installed in the orbiter's rear compartment.

The payload bay doors are opened, and access provisions are installed to support payload operations. Any hazardous payloads are also rendered safe during these early OPF operations.

Payloads and the associated airborne support equipment from the previous flight are removed from the orbiter payload bay, and the bay is prepared for the installation of new payloads. The remote manipulator system arm is removed or installed, as required for the next mission.

During routine deservicing operations, non-storable consumables are off-loaded from the orbiter and waste products are removed. Potable water, water from the water spray boilers and lube oil from the auxiliary power units are drained, and APU lube oil filters are removed.

After initial safing is completed, postflight troubleshooting of anomalies that occurred during launch, flight or re-entry begins.

Orbiter components are removed and repaired or replaced as required based on anomaly reviews and then retested in parallel with other processing activities.

Visual inspections are made of the orbiter's thermal protection system, selected structural elements, landing gear, tires and other systems to determine if they sustained any damage during flight and landing.

Any damage to the thermal protection system must be repaired before the next mission. TPS operations are conducted in parallel with most of the activities in the Orbiter Processing Facility. There are some 27,446 tiles and thermal blankets on the outside of each orbiter and some 6,000 thermal control blankets on the inside.

TPS maintenance is provided in the new Thermal Protection System Facility across the street from the OPF. The 33,000-square- foot facility was located near the OPF to minimize the time it takes to transport the tiles and thermal control system blankets between the two facilities. Several trips are required before the tiles and some blankets are installed on the orbiter. The closeness of the facilities is also expected to minimize damage to the delicate tiles.

During OPF processing, any vehicle modifications required in addition to routine postflight deservicing/servicing and checkout are performed. Planned modifications are typically put into work as soon as practical after the orbiter returns and are completed in parallel with prelaunch servicing whenever possible.

Modifications may be performed to meet future mission requirements, resolve an identified deficiency or enhance vehicle performance by replacing existing hardware with new, improved designs.

Orbiter modifications, if they are extensive, may be performed with the vehicle powered down. Many modifications, however, can be completed in parallel with routine servicing while the orbiter is powered up.

Where possible, modification work is completed in the OPF and Orbiter Modification and Refurbishment Facility while the orbiter is in a horizontal position. While some modification work can be carried out in the Vehicle Assembly Building or on the pad if necessary, the OPF and OMRF offer the best access and support equipment for conducting such work.

Except during hazardous operations, routine preflight servicing can begin while deservicing activities are still under way or modifications are in work. Routine servicing includes reconfig uring orbiter systems for flight, performing routine maintenance, replacing parts and installing new mission flight kits and payloads. Consumable fluids and gases are loaded aboard, and the APU lube oil system is serviced.

As systems servicing is completed, functional checks are performed to verify flight readiness prior to closeout. Any system that fails the functional check undergoes troubleshooting to identify the problem. If required, subsequent repairs or replacements are performed.

The orbiter's hydraulically activated flight control surfaces are thoroughly checked out.

A new payload may be installed in the OPF before shuttle vehicle integration or at the launch pad after shuttle integration. Depending on the particular mission, new payloads could be installed at both locations. If payloads are installed in the OPF, the orbiter-to-payload interfaces are verified before the orbiter is moved to the VAB.

A crew equipment interface test is performed during the OPF flow to identify any problems associated with flight crew equipment.

Following all space shuttle main engine work, the orbiter's main propulsion system, including the three main engines, undergoes a helium signature leak check. Successful completion of this test generally clears the way for the closeout of the aft engine compartment.

Electrically initiated pyrotechnic devices (ordnance) required for orbiter systems are installed and checked out. These include small explosive charges like those used for the backup deployment of the orbiter landing gear or emergency jettison of the remote manipulator system, Ku-band antenna, side hatch jettison and secondary emergency egress jettison.

Upon completion of all payload installation activities or any other work being performed in the payload bay, the clamshell-shaped payload bay doors are closed and latched. If no payloads are to be installed at the pad, this represents final closeout of the orbiter midbody for flight.

The final tasks to be completed in the OPF before the orbiter is moved to the Vehicle Assembly Building are to weigh the orbiter and determine its center of gravity. Vehicle performance is affected by both weight and center of gravity, and flight programming requires an accurate determination of both parameters.

All ground support and access equipment is then removed, and the orbiter is towed into the Vehicle Assembly Building transfer aisle through the large door at the north end of the high bay.

    The OMRF was designed as a third bay where space shuttle orbiters could be inspected, repair work and off-line modifications could be performed, and orbiters could be stored. It is located north of the Orbiter Processing Facility.

The OMRF high bay is 197 feet long, 150 feet wide and 95 feet high, the same as the two OPF bays. The facility's electrical, mechanical and communications control rooms are located in an adjacent support bay. There is office space for personnel and a conference room with a window that overlooks the processing bay.

Only non-hazardous work will be performed in the OMRF until it is properly outfitted like the OPF to handle hazardous operations. In the meantime, work on the orbiter includes most thermal protection system operations, thermal protection system rewaterproofing, modifications that the facility can support and general maintenance.

Future upgrades to the facility will allow safing and deservicing limited orbiter power-up using mobile electrical ground power servicing of the orbiter's power reactant storage and distribution system dumping of the orbiter's flight recorders, which requires support of the Launch Control Center computers servicing of the orbiter's Freon coolant loop systems and other tests requiring support of the Launch Control Center.

    The Logistics Facility is a 324,640-square-foot building located south of the Vehicle Assembly Building. It houses 190,000 space shuttle hardware parts, and about 500 NASA and contractor personnel work there. The most unusual feature of the Logistics Facility is its state-of-the-art parts retrieval system, which includes automated handling equipment to find and retrieve specific space shuttle parts.
    The Vehicle Assembly Building, built for the vertical assembly of Saturn launch vehicles, is the heart of Launch Complex 39 and was modified to support the assembly of the space shuttle.

One of the largest buildings in the world, the VAB covers 8 acres and has a volume of 129,428,000 cubic feet. It is 525 feet tall, 715 feet long and 518 feet wide. The building is divided into a 525-foot-tall high bay and a 210-foot-tall low bay. A transfer aisle running north and south connects and transects the two bays, permitting easy movement of vehicle elements.

The high bay is divided into four separate bays. The two on the west side of the structure-Bays 2 and 4-are used for storing space shuttle orbiter external tanks. The two bays facing east-Bays 1 and 3-are used for the vertical assembly of space shuttle vehicles on the mobile launcher platform.

Extendable platforms, modified to fit the space shuttle configuration, move in around the vehicle to provide access for integration and final testing. When checkout is complete, the platforms move back, and the VAB doors are opened to permit the crawler-transporter to move the mobile launcher platform and assembled space shuttle vehicle to the launch pad. The high bay door is 456 feet high. It is divided into lower and upper sections. The lower door is 152 feet wide and 114 feet high with four door leaves that move horizontally. The upper door is 342 feet high and 76 feet wide with seven door leaves that move vertically.

The low bay was the initial site for refurbishment and subassembly of solid rocket booster segments. These activities now occur at a new facility north of the VAB.

Existing pneumatic, environmental control, light and water systems have been modified in both bays. The north doors to the VAB transfer aisle have also been widened 40 feet to permit the orbiter to enter when it is towed over from the Orbiter Processing Facility. The doors are slotted at the center to accommodate the orbiter's vertical stabilizer.

The Vehicle Assembly Building has more than 70 lifting devices, including two 250-ton bridge cranes.

The VAB is designed to withstand winds of up to 125 miles per hour. Its foundation rests on more than 4,200 open- end steel pilings 16 inches in diameter driven down 160 feet to bedrock.

    The external tank is transported to the Kennedy Space Center.by barge from Martin Marietta's Michoud assembly facility at New Orleans, La. On arrival at the space center, the tank and the associated hardware are off-loaded at the barge turn basin. The external tank is transported horizontally to the Vehicle Assembly Building on a wheeled transporter and is transferred to a vertical storage or checkout cell. High Bays 2 and 4 each contain one external tank storage and one checkout cell.

The storage cells provide only the minimum access and equipment required to secure the external tank in position. After the tank is transferred to the checkout cell, permanent and mobile platforms are positioned to provide access to inspect the tank for possible damage during transit and to remove hoisting equipment. The liquid oxygen and liquid hydrogen tanks are then sampled and receive a blanket pressure of gaseous nitrogen and gaseous helium, respectively, in preparation for a normal checkout.

The external tank subsystem checkout includes an inspection of the external insulation and connection of ground support equipment (including the launch processing system) to the appropriate interfaces. Electrical, instrumentation and mechanical function checks and tank and line leak checks are performed in parallel.

After satisfactory checkout of the external tank subsystems, ground support equipment and launch processing system equipment are removed and stored, and external tank closeout is initiated. Forward hoisting equipment is attached and work platforms are stored-or opened-in preparation for transferring the tank to the mobile launcher platform.

The external tank is hoisted vertically from the checkout cell by the 250-ton high bay crane and transferred to the mobile launcher platform in High Bay 1 or 3 for mating with the already-assembled solid rocket boosters. After the external tank and solid rocket booster are mated, the integration cell ground support equipment is connected, and intertank work platforms are installed.

A considerable amount of final closeout work is performed on the boosters and the tank after they are mated.

    The space shuttle main engine workshop is located in the Vehicle Assembly Building in a low bay checkout cell that was converted into an enclosed, environmentally controlled engine workshop. The workshop serves as a receiving and inspection facility for SSMEs and as a support facility for all SSME operations at Kennedy.

Three engine workstands are available to support major stand-alone engine work, if required. The facility can support main engine disassembly and reassembly, checkout and leak testing.

Engines, mounted on engine handling devices and protected by a cylindrical shipping cover, arrive by truck from NASA's National Space Technology Laboratories and are off-loaded in the VAB transfer aisle next to the engine workshop. The engines are then pulled into the workshop and undergo receiving inspections. Normally, newly delivered engines are transferred to an engine installer and transported to the Orbiter Processing Facility for installation.

Routine postflight deservicing of the engines is performed in the OPF with the engines in place aboard the orbiter. More extensive between-flight servicing can be performed in the main engine workshop. The shop also supports engine removal operations and the preparation of engines for shipment back to NSTL or Rocketdyne in Canoga Park, Calif., the manufacturer of the SSMEs.

The shop provides storage for test equipment and serves as a staging area for SSME operations performed in the OPF and VAB and at the launch pad.

    The solid rocket motor segments and associated hardware are shipped to the Kennedy Space Center.by rail from the contractor's facility in Utah. The segments are transported horizontally and have transportation covers. End rings provide segment handling points, environmental protection, and protection of the solid-grain propellant and the outer edge of each segment from potential impact damage.

When they arrive at KSC, the segments are delivered to the solid rocket motor Rotation, Processing and Surge Facility, a group of steel-framed structures designed to withstand hurricane-force winds.

The RPSF, located north of the Vehicle Assembly Building, comprises a processing facility, a support building and two segment surge (storage) buildings. The facilities isolate hazardous operations associated with solid rocket motor rotation and processing (formerly performed in High Bay 4 of the VAB) and avert impacts to VAB launch-support capabilities.

The rotation building is 98.6 feet high and has an area of 18,800 square feet.

The main facility in the complex is used for solid rocket motor receiving, rotation and inspection and supports aft booster buildup. Rail tracks within the building permit railroad cars containing the segments to be positioned directly under one of the two 200-ton overhead bridge cranes. A tug vehicle capable of pulling and stopping a fully loaded segment car moves and positions railcars in the building.

Recovered booster segments are loaded onto railcars for shipment back to the manufacturer at a site on Contractor Road.

Two surge buildings located nearby contain 6,000 square feet each of floor area for storage of eight segments (one flight set). The buildings are 61 feet in height in the aft segment storage area and 43 feet in the forward and center segment storage area.

Paved roads between the processing facility, the two storage buildings and the VAB permit transporters to transfer the segments and other hardware from one facility to another.

Live solid rocket motor segments arrive at the processing facility and are positioned under one of the cranes. Handling slings are then attached to the railcar cover, and it is removed. The segment is inspected while it remains in the horizontal position.

The two overhead cranes hoist the segment, rotate it to the vertical position and place it on a fixed stand. The aft handling ring is then removed. The segment is hoisted again and lowered onto a transportation and storage pallet, and the forward handling ring is removed to allow inspections. It is then transported to one of the surge buildings and temporarily stored until it is needed for booster stacking in the VAB.

In 1986, a new Solid Rocket Booster Assembly and Refurbishment Facility was constructed at KSC after recompetition of the Marshall Space Flight Center's booster assembly contract.

Solid rocket booster operations are performed by both the shuttle processing contractor and the booster assembly contractor, who is responsible for booster disassembly and refurbishment and the assembly and checkout of forward and aft skirt subassemblies in the VAB. Booster retrieval operations, parachute refurbishment and booster stacking activities, in addition to integrated checkout, are performed by the shuttle processing contractor.

Refurbishment and subassembly operations previously performed in the VAB low bay and other outlying facilities are now conducted in the new facility located south of the VAB.

Aft skirts, fully configured and checked out in the Solid Rocket Booster Assembly and Refurbishment Facility, are delivered to the RPSF on dollies and hoisted into position on workstands. An inspected aft segment is then hoisted into position for mating with the aft skirt. When the aft segment assembly is completed and transferred to a pallet, it is transported directly to the VAB or to one of the two storage buildings.

Solid rocket booster elements, such as forward skirts, aft skirts, frustums, nose caps, recovery systems, electronics and instrumentation components, and elements of the thrust vector control system are received in this facility.

Assembly and checkout of the forward assembly (nose cap, frustum and forward skirt) and aft skirt assembly are also performed here in addition to refurbishment of recovered booster flight hardware.

The structural assemblies and components required to build up the forward assembly, aft skirt and external tank attach hardware are either shipped to KSC new or refurbished on site.

When completed, the aft skirt assemblies are transferred to the RPSF for assembly with the aft solid rocket motor segments.

An SRB hydraulic power unit ''hot fire'' facility is located in the southeast corner of the 44-acre site. The facility features a test stand that supports the hot-firing of the solid rocket booster's hydrazine-fueled thrust vector control system. Before each flight, the solid rocket booster aft skirt assemblies containing the TVC are transported to the facility and test-fired before the aft booster buildup.

The stacking of the solid rocket booster major assemblies begins after the buildup of aft booster assemblies at the Solid Rocket Motor Processing Facility (north of the VAB) and checkout of the forward nose skirt assemblies in the Solid Rocket Booster Assembly and Refurbishment Facility.

The booster stacking operation is accomplished in the following sequence:

1. The aft booster assemblies are transferred from the buildup area in the Rotation, Processing and Surge Facility to the High Bay 1 or 3 integration cells in the VAB and attached to the mobile launcher platform support posts.

2. Continuing serially, the aft, aft center, forward center and forward rocket motor segments are stacked to form complete solid rocket motor assemblies. As each segment is mated, the joint seal is inspected visually.

3. Segment seal integrity is then demonstrated by a leak check and decay test between the redundant seals. The forward skirt/nose assemblies are transferred from the SRB ARF to the High Bay 1 or 3 integration cell and stacked atop the completed solid rocket motor assemblies to form a complete set of boosters.

An alignment check of the complete flight set of solid rocket booster assemblies is performed after the stacking operations are completed. Integrated and automated systems testing of the assembled solid rocket boosters is accomplished on the mobile launcher platform, using the launch processing system to simulate the external tank and orbiter.

Before the space shuttle vehicle is transferred to the launch pad, solid rocket booster flight batteries are installed. Final connection of the solid rocket booster pyrotechnic systems is performed at the launch pad.

The solid rocket booster's hydraulic power units are serviced with hydrazine during the prelaunch propellant-servicing operations at the launch pad.

    The Hypergolic Maintenance and Checkout Facility consists of three buildings in an isolated section of the KSC industrial area approximately eight miles southeast of the Vehicle Assembly Building. This area provides all facilities required to process and store the hypergolic-fueled modules that make up the orbiter's reaction control system, orbital maneuvering system and auxiliary power units.
    The orbiter is towed from the Orbiter Processing Facility into the transfer aisle of the Vehicle Assembly Building through the north door. When the orbiter is in position, the lifting beams are installed, and the erection slings are attached. The orbiter is then lifted, and the landing gear is retracted. The orbiter is rotated from the horizontal to the vertical position using the 250- and 175-ton cranes. It is then transferred to the space shuttle assembly area in High Bay 1 or 3 and lowered and mated to the external tank, which is already mated with the solid rocket boosters on the mobile launcher platform. After mating is completed, the erection slings and load beams are removed from the orbiter, and the platforms and stands are positioned for orbiter/external tank/solid rocket booster access. The orbiter is mated with its fin toward the transfer aisle (toward the south at the pad).
    After the orbiter has been mated to the external tank/solid rocket booster assembly and all umbilicals have been connected, an electrical and mechanical verification of the mated interfaces is performed to verify all critical vehicle connections. A shuttle interface test is performed using the launch processing system to verify space shuttle vehicle interfaces and space shuttle vehicle-to-ground interfaces. The launch processing system is used to control and monitor orbiter systems as required in the Vehicle Assembly Building. After interface testing is completed, ordnance devices are installed, but not electrically connected. Final ordnance connection and flight closeout is completed at the pad.

Almost complete external access to the shuttle vehicle is provided in the Vehicle Assembly Building. Access to the payload bay is through the crew compartment since the payload bay doors cannot be opened in the Vehicle Assembly Building.

    The mobile launcher platforms are the movable launch bases for the space shuttle. Two platforms are in operational use and a third is being modified for future use. The platforms were used for the Saturn/Apollo missions and were modified for the space shuttle.

The mobile launcher platform is a two-story steel structure 25 feet high, 160 feet long and 135 feet wide. It is constructed of welded steel up to 6 inches thick. At their park site north of the Vehicle Assembly Building, in the Vehicle Assembly Building high bays and at the launch pad, the mobile launcher platforms rest on six 22-foot- tall pedestals.

Three openings are provided in the mobile launcher platform-two for solid rocket booster exhaust and one for space shuttle main engine exhaust. The solid rocket booster exhaust holes are 42 feet long and 20 feet wide. The space shuttle main engine exhaust opening is 34 feet long and 31 feet wide.

Inside the platform are two levels with rooms and compartments housing launch processing system hardware interface modules, system test sets, propellant-loading equipment and electrical equipment racks.

Unloaded, the mobile launcher platform weighs 8.23 million pounds. The total weight with an unfueled space shuttle aboard is 11 million pounds.

The space shuttle vehicle is supported and restrained on the mobile launcher platform during assembly, transit and pad checkout by the solid rocket booster support/hold-down system. Four conical hollow supports for each booster are located in each solid rocket booster exhaust well. The supports are 5 feet high and have a base diameter of 4 feet.

Posts on the aft skirts of the SRBs rest on spherical bearings atop the mobile launcher platform hold-down posts. A 28-inch-long, 3.5-inch-diameter stud passes vertically through the SRB post, spherical bearing and hold-down post casting to secure the booster to the platform. A frangible, or explosive, nut at the top of the stud and a nut at the bottom are tightened to preload the stud to a tension of up to 850,000 pounds.

When full main engine thrust is developed during the final moments of the launch countdown, ignition signals are sent to the two SRBs. Simultaneously, the explosive nuts at the tops of the studs are triggered. The preloaded studs are expelled downward into deceleration stands (''sandbuckets'') and the fractured halves of the explosive nuts are contained within spherical, 10-inch-diameter debris catchers on top of the solid rocket booster aft skirt posts. This sequence releases the solid rocket boosters and the entire space shuttle vehicle for flight.

Two tail service masts, one located on each side of the space shuttle main engine exhaust hole, support the fluid, gas and electrical requirements of the orbiter's liquid oxygen and liquid hydrogen aft T-0 umbilicals. The TSM assembly also protects the ground half of those umbilicals from the harsh launch environment. At launch, the solid rocket booster ignition command fires an explosive link, allowing a 20,000-pound counterweight to fall, pulling the ground half of the umbilicals away from the space shuttle vehicle and causing the mast to rotate into a blastproof structure. As it rotates backward, the mast triggers a compressed-gas thruster, causing a protective hood to move into place and completely seal the structure from the main engine exhaust.

Each TSM assembly rises 31 feet above the mobile launcher's deck, is 15 feet long with umbilical retracted, and is 9 feet wide. The umbilical carrier plates retracted at launch are 6 feet high, 4 feet wide and 8 inches thick, or about the size of a thick door.

The liquid oxygen umbilical runs through the TSM on the east side of the mobile launcher, and the liquid hydrogen umbilical runs through the TSM on the west.

Gaseous hydrogen, oxygen, helium and nitrogen ground and flight system coolants ground electrical power and ground-to-vehicle data and communications also flow through the TSM umbilical links.

Work platforms used in conjunction with the mobile launcher platform provide access to the space shuttle main engine nozzles and the solid rocket boosters after they are erected in the Vehicle Assembly Building or while the space shuttle is undergoing checkout at the pad.

The main engine service platform is positioned beneath the mobile launcher platform and raised by a winch mechanism through the exhaust hole to a position directly beneath the three engines. An elevator platform with a cutout may then be extended upward around the engine bells. The orbiter engine service platform is 34 feet long and 31 feet wide. Its retracted height is 12 feet, and the extended height is 18 feet. It weighs 60,000 pounds.

Two solid rocket booster service platforms provide access to the nozzles after the vehicle has been erected on the mobile launcher platform. The platforms are raised from storage beneath the mobile launcher into the solid rocket booster exhaust holes and hung from brackets by a turnbuckle arrangement. The solid rocket booster platforms are 4 feet high, 20 feet long and 20 feet wide. Each weighs 10,000 pounds.

The orbiter and solid rocket booster service platforms are moved down the pad ramp to a position outside the exhaust area before launch.

    Tracked crawler-transporter vehicles move the space shuttle vehicles between the Vehicle Assembly Building and Launch Complex 39-A or 39-B. The two transporters are 131 feet long and 114 feet wide. They move on four double-tracked crawlers, each 10 feet high and 41 feet long. Each shoe on th crawler track weighs 2,000 pounds. The transporter's maximum speed unloaded is 2 mph loaded, it is 1 mph. Unloaded, it weighs 6 million pounds.

The transporters have a leveling system designed to keep the top of the space shuttle vehicle vertical within plus or minus 10 minutes of arc-about the dimensions of a basketball. This system also provides the leveling operations required to negotiate the 5-percent ramp leading to the launch pads and to keep the load level when it is raised and lowered on pedestals at the pad and in the Vehicle Assembly Building.

The overall height of the transporter is 20 feet, from ground level to the top deck, on which the mobile launcher platform is mated for transportation. The deck is flat and about the size of a baseball diamond (90 feet square).

Each transporter is powered by two 2,750-horsepower diesel engines. The engines drive four 1,000-kilowatt generators that provide electrical power to 16 traction motors. Through gears, the traction motors turn the four double-tracked crawlers spaced 90 feet apart at each corner of the transporter.

North of the Orbiter Processing Facility is a weather-protected crawler-transporter maintenance facility in which components of the crawler-transporters can be repaired or modified. It includes a high bay with an overhead crane for lifting heavy components and a low bay for shops, parts storage and offices. A pit has been built outside on the crawlerway to accommodate track segment removal and installation.

The crawler-transporters move on a roadway 130 feet wide, almost as broad as an eight-lane turnpike. The crawlerway from the VAB to the launch pads consists of two 40-foot-wide lanes separated by a 50-foot-wide median strip. The distance from the Vehicle Assembly Building to Launch Complex 39-A is 3.4 miles and 4.2 miles to Launch Complex 39-B. The roadway is built in three layers with an average depth of 7 feet. The top surface is river gravel. The gravel is 8 inches thick on curves and 4 inches on straightaway sections.

When the space shuttle vehicle is fully assembled and checked out in the VAB, the crawler-transporter is driven into position beneath the mobile launcher platform. The transporter jacks the mobile launcher off its pedestals, and the rollout to the launch pad begins. It takes approximately five hours for the unusual transport vehicle to make the trip from the VAB to the launch pad. During the transfer, engineers and technicians aboard th crawler, assisted by ground crews, operate and monitor systems while drivers steer the vehicle towards its destination.

After the mobile launcher platform is ''hard down'' on the launch pad pedestals, th crawler is backed down the ramp and returned to its parking area.


Space Shuttle Crawler - HISTORY

Terex Crawler Lifts Space Shuttle Discovery Into History

Space Shuttle Discovery, the most traveled shuttle in NASA’s fleet, ended its voyage at Washington Dulles International Airport this spring after more than 150 million miles of airtime. Its final flight took place April 17, 2012, on top of a Boeing 747 Shuttle Aircraft Carrier, where it was slated to replace the Space Shuttle Enterprise at the Smithsonian Institution’s James S. McDonnell Space Hangar at the Steven F. Udvar-Hazy Center. Before being towed from Dulles to its final exhibit place, Discovery had to be hoisted from its carrier and its landing gear lowered into place one final time, which happened with help from a Terex CC2800-1 crawler crane and South Kearny, N.J.-based J.F. Lomma Inc.’s crane and rigging team.

Lomma and the United Space Alliance work crews methodically hoisted the 196,400-pound shuttle off of the 747 Shuttle Aircraft Carrier (SAC). “You cannot describe what it’s like to be part of space shuttle history,” said Frank Signorelli, crane and rigging manager for J. F. Lomma, Inc. Josh Barnett, field service representative for Terex Cranes, who was on site to support Lomma on the lift, added, “It was a one-of-a-kind experience.”

For Lomma, planning for this job started nearly two years ago when company officials first considered bidding for the job. NASA was very specific in what equipment was required for the work. “The bid called specifically for the Terex CC 2800-1 as the primary crane to do the pick as well as all of the other supporting cranes and equipment,” Signorelli said.

Part of the reason for this lies with NASA’s experience with this crane model for a similar pick decades ago. When the 747 SAC transports the space shuttle to a place other than a space center, there is a need for crane and rigging equipment. “These picks do not happen often, since NASA already has a shuttle removal method in place at each space center,” Barnett explained.

In the early 1990s, NASA had the rare need to hoist a shuttle from the 747 SAC, and a Terex legacy brand was selected for the job. “A Demag 2800 crawler crane was used in that project as the primary crane,” mentions Jim Creek, Terex Cranes’ senior product manager for crawler cranes – North America. “NASA has a history of successful lifts with this crane.”

The Terex crane for this job, the CC 2800-1, offers a 660-ton capacity at a 32.8-foot radius, more than enough to handle Discovery’s weight. It features a maximum 196.9-foot main boom length and a variable 100-foot radius Superlift attachment to boost lift capacities. “Superlift offers an additional 4,000 to 600,000 lb (1,814 to 272,155 kg) of counterweight on the tray, which enables the crane to lift more weight further from the crane’s base,” said Creek.

The shuttle project consisted of not one but two shuttle hoists. The first lifted the Space Shuttle Discovery off of the 747 SAC for the shuttle’s eventual spot at the Smithsonian. The second loaded the Space Shuttle Enterprise onto the carrier, so it could be flown to John F. Kennedy International Airport in New York.

It took Lomma nearly three months to prepare for and arrange the pick. “We had conference calls with NASA two times a week,” Signorelli said. “Communication was often and thorough between our company and NASA.”

Lomma purchased the CC 2800-1 two years ago. It was on rent with a customer in Quebec. Upon returning to the yard, the crane was rigged to make sure the right components were in place for the job. “We ran the crane in our yard,” Signorelli said. “The (IC-1) computer screen is extremely user friendly and self-explanatory. It’s not a complicated crane to operate.”

Upon completing the dry run at the yard, Lomma disassembled the crane and sent the components to the jobsite. Lomma’s crews spent three days at Dulles rigging the CC 2800-1 and a fourth day running through test lifts to make sure everything would go smoothly.

Making The Lift

When it came time for the shuttle pick, there was very little left to question. “NASA had everything marked out on the ground—positioning for the Terex crane, the supporting crane, and the 747,” explained Signorelli.

The CC 2800-1 crawler crane was equipped with a 177-foot main boom and a 98-foot Superlift mast. Lomma used 352,000 pounds of main counterweight with no central ballasts. Superlift counterweight of 275,000 pounds was added to the tray 50 feet from the crane base. “Normally, a lift like this would require only 220,000 pounds on the Superlift, but NASA’s additional safety factor required an extra 55,000 pounds on the tray,” explained Barnett.

The additional safety requirement stemmed from the need for workers to be under the live load while unhooking the shuttle from its 747 SAC. “NASA required a 75 percent derate from the crane’s standard 85 percent chart, which is a big safety factor,” said Signorelli.

In the overnight hours, when airport activities were at a lull and winds were calm, Lomma and United Space Alliance crews began the removal of the shuttle. The 747 SAC, supporting crane lifting the front of the shuttle, and CC 2800-1 lifting the heavier back end, were all positioned according to NASA’s layout.

NASA engineers used calculations from the CC 2800-1’s IC-1 controls to map out the final position of the crane. “They wanted the connection between the shuttle and our crane to be at 112 feet,” said Barnett, “and the actual distance in the field from the center of the crane to the hook was 111.9 ft (34.1 m). They were impressed with IC-1’s accuracy.”

Slowly and with precision, the pick began with the weight shifting and then transferring to the cranes as the brackets were removed from the shuttle and carrier. After the shuttle hovered a safe distance over the carrier, a pushback tug backed it from underneath the shuttle. The shuttle was then lowered to within a few feet of the ground. Auxiliary hydraulic power lowered the shuttle’s landing gear for a final time before the cranes lowered it to the ground.

“The subtle movements offered by the CC 2800-1’s hydraulic system definitely helped with this pick,” said Barnett. “If the crews only needed 0.5 inch of movement, the crane was able to give it to them.”

A few days later, Discovery was towed to the Smithsonian and replaced the Space Shuttle Enterprise, which had been on display inside the James S. McDonnell Space Hangar since 2003. This prompted a second pick and final move of the Enterprise to its new home in New York.

Moving the Enterprise

Within a week after the Discovery pick, Lomma’s crews were back at Dulles, this time to reverse the process and load Enterprise on the 747 SAC. With one hoist project already completed, the second pick of the Enterprise went equally as smooth as the Discovery effort. “Enterprise was actually much lighter than Discovery, so we had no issues,” said Signorelli.

A lesser known, but vital link to the shuttle program, Enterprise never made a trip to outer space. It was constructed in the mid-1970s as a prototype tester for what became the final space shuttle design. NASA engineers ran it through a number of flight and landing test simulations to prove the validity of the concept. While NASA initially intended to retrofit Enterprise for space travel, several final shuttle design changes kept it grounded.

Enterprise, via the 747 SAC, took off from Dulles on April 27 for its final home in New York City and landed at JFK International Airport. At the same time, the CC 2800-1 crane components were derigged and loaded onto trucks and trailers heading for New York. Once arriving at JFK, the crane equipment was rigged, tested, and ready for another shuttle pick.

Originally scheduled for the morning hours of May 14, the Enterprise pick was moved up due to inclement weather. “Projected wind speeds were predicted to approach NASA’s 10 mph, which was the wind speed limit for removing the shuttle from its carrier,” said Signorelli.

Even though the CC 2800-1’s configuration for the Enterprise pick was rated for a maximum wind speed of 25 mph, NASA’s tighter wind threshold was followed. “Therefore, they moved the pick up two days to start on May 12,” he added.

Under clear weather conditions and wind speeds flirting with NASA’s threshold, Lomma began the pick just before midnight. Similar with the Discovery project at Dulles, careful planning and constant communication allowed the pick to be completed successfully.


Launch Complex 39: From Saturn to Shuttle to SpaceX and SLS

When astronauts Doug Hurley and Bob Behnken lift off on the SpaceX Crew Dragon Demo-2 mission to the International Space Station (ISS) soon, they will depart from Kennedy Space Center’s historic Pad 39A. It is the same one used by the last NASA astronauts to launch from American soil, the Space Shuttle Atlantis crew in July 2011. Indeed, Launch Complex 39 A and B have been the site of every U.S. human spaceflight that went into orbit since December 1968, including the Apollo 11 lunar landing. That exclusivity will end eventually, as Boeing will launch its Starliner crews to the ISS from the Space Force side of Cape Canaveral, but NASA’s LC-39 (Launch Complex 39) will continue to serve long into the future.

In 1961, when President John F. Kennedy tasked the National Aeronautics and Space Administration (NASA) with landing humans on the Moon by the end of the decade, the agency had no launch pads or stand-alone center in Florida. Its units were tenants on Cape Canaveral Air Force Station, along with the Army, Navy, and other government organizations. All of NASA’s early human spaceflight missions, and most satellite and space probe flights, lifted off from the USAF facility, which was part of the Atlantic Missile Range. Pads were numbered in the order they were built, starting near the tip of Cape Canaveral and running north, mostly in numerical order. The Mercury-Redstone missions used LC-5, Mercury-Atlas LC-14, and Gemini-Titan LC-19. The last astronauts to lift off from the Air Force side were the Apollo 7 crew on a Saturn IB from LC-34 in October 1968.

The Moon landing challenge immediately confronted NASA, however, with the need for a much bigger rocket. Early plans imagined a booster even larger than the Apollo Saturn V turned out to be. The question was where to fire such a monster an accident could unleash the force of a small nuclear weapon. Ideas included Florida, the Georgia Sea Islands, and islands in the Pacific, but the agency soon decided to take a large tract on Merritt Island, just north of the Cape, for LC-39. That meant a massive expansion of NASA’s Florida activity. The Cape-based launch division of Wernher von Braun’s Marshall Space Flight Center in Alabama was spun off as the Launch Operations Center in 1962. It acquired its present name, John F. Kennedy Space Center (KSC), immediately after President Kennedy’s assassination in November 1963.

Engineers at NASA and its contractors also quickly decided they needed a new way to assemble and launch such a gigantic rocket. The reigning method was to stack the vehicle and its payload on the pad, usually inside a service structure that would be pulled back before launch. That could take months when problems cropped up, with some exposure to the elements. It was actually inferior to the Soviet system, which was to assemble the rocket horizontally inside a building on a rail-car erector/launcher. They could roll the vehicle out, set it upright, and launch it in one day, demonstrating that capability by orbiting cosmonauts on consecutive days from the same pad in August 1962. American engineers had no insight into that, but decided that they needed their own mobile launch system. Based on the existing tradition, they decided to stack the rocket vertically on a mobile platform inside a building, then move the platform and rocket out to the pad. The question was how? After looking at several ideas, including barges in the subtropical wetlands that were Merritt Island, they settled on a gigantic tracked vehicle. Strip-mining machines inspired the now-iconic Crawler-Transporter.

The Apollo 14 Saturn V emerges from the Vehicle Assembly Building (VAB) in November 1970, on its way to Pad 39A.

The rockets would be stacked inside the Vertical (later Vehicle) Assembly Building (VAB), which was for a time the world’s largest enclosed human structure. Based on NASA’s optimism about its future in the mid-sixties, it was overbuilt, with four vertical bays, each one of which could contain a Saturn V. There were to be three launch pads, LC-39A, B, and C, but the last was never built. B was constructed largely as a backup, in case a rocket explosion destroyed A. It was used only for Apollo 10, the dress rehearsal for the landing, because it launched only two months before Apollo 11, and preparations for that mission were already underway at 39A.

The first astronauts to launch from LC-39A were the Apollo 8 crew, Frank Borman, Jim Lovell, and Bill Anders, on the first mission to the Moon, the Christmas 1968 flight to lunar orbit. After Apollo, the Skylab space station, a converted Saturn V third stage on two active stages, also flew from A. But all three Skylab crews ascended to space from 39B on Saturn IBs. To save money, NASA mothballed the old Saturn IB Pads 34 and 37, and put a “milk stool” on one of the launch platforms, lifting the rocket over a hundred feet so that the rocket’s second stage, which was the same as the Saturn V’s third, would be at the right height for the propellant lines, cables, and astronaut access arm. KSC used that odd-looking launcher and Pad 39B for the Apollo Soyuz Test Project in 1975 as well. Then, no American astronauts flew for nearly six years—the longest hiatus ever. (Since 2011, Americans have been riding Russian Soyuz spacecraft to and from the ISS in the absence of a U.S. launcher.)

NASA’s next human spaceflight program, the Space Shuttle, was much delayed and on a tight budget, so the agency adapted LC-39 to the winged vehicle. KSC stacked the much shorter shuttle inside the tall bays of the VAB and took the gantry tower off the launch platform and installed it on the pad. The shuttle rode out to the launch pad on a bare platform. A rotating service structure then moved to cover the shuttle and provide access to the payload bay. The first shuttle launch left from 39A in April 1981, as did the next 23. Pad B’s refitting was delayed by budget problems, so its first launch unfortunately was the Challenger disaster of January 1986, killing Teacher-in-Space Christa McAuliffe and six NASA astronauts. After the shuttle returned to flight in 1988, the two pads were used almost equally for the next 20 years. Then B was taken out of service to retrofit for President George W. Bush’s soon-to-be-canceled Constellation Moon landing program.

After the last shuttle mission in 2011, NASA, once again looking for ways to save money, decided to lease out Pad 39A. After a contentious bidding process, it awarded a 20-year lease to SpaceX in 2013/14. The company’s engineers have modified it so that it can host either Falcon 9 or Falcon Heavy (which has three Falcon 9 first stages bolted together) rockets. Whether the Russians have had any influence, I don’t know, but SpaceX built a horizontal assembly building next to 39A, with a wheeled erector/launcher to take the complete vehicle out and set it upright. It later added a new launch umbilical tower with an astronaut access arm for Crew Dragon launches on Falcon 9.

A SpaceX Falcon 9 rocket with the Crew Dragon spacecraft is raised into position on Pad 39A ahead of the Demo-2 mission to the International Space Station in May 2020.

As for LC-39B, it has been outfitted for multiple vehicles, but its primary purpose will be to host the gigantic Space Launch System (SLS) rocket, a Saturn-V-sized monster that will send American astronauts to the Moon again. The first unpiloted test, Artemis 1, has repeatedly slipped, but is planned for late 2021. NASA recently completed the modification of the VAB, launch platforms, and the pad for SLS, so we will see the Crawler-Transporter hauling a rocket out to the launch pad again. In 2015, the agency also built a new 39C pad for small, commercial satellite launch vehicles, but it does not appear to have been used yet.

Thus, when Bob Behnken and Doug Hurley take off, they will ascend from a historic pad, one used for the first human trips to the Moon and many important shuttle flights. Launch Complex 39 will continue to support groundbreaking journeys in the human exploration of space well into the future, more than 50 years after its baptism-by-fire in the first Saturn V launch in 1967.

Michael J. Neufeld is a senior curator in the Museum’s Space History Department and is responsible for the rocket and missile and Mercury/Gemini spacecraft collections.


Space Shuttle Crawler - HISTORY

    General Information : Basic information about each mission in the Space Shuttle. : Technical details on the orbiter. : A fine collection of materials relating to each Space Shuttle mission including an impressive collection of images. Rich Orloff has scanned and formatted press kits for all the Shuttle flights except for dedicated DoD missions KSC Historical Report 19, KHR-19, Rev. April 2006. This summary of the United States Space Shuttle Program firsts was compiled from various reference publications available in the Kennedy Space Center Library Archives.

Papers and Technical Information : Info on the "glass cockpit" and other advanced technologies. this is a good resource for basic technical data. . A paper arguing that lessons learned from early attempts to use atmospheric flight navigation should be studied to lower the probability of schedule slips and cost overruns on future programs. . A paper arguing that lack of insight into GNSS software complicates the integration and test process. . A list of papers on Space Shuttle avionics. . Space Shuttle orbiter technical diagrams from Space Shuttle News Reference (NASA).


Space Shuttle Challenger

Space Shuttle Challenger (OV-099) was a Space Shuttle orbiter manufactured by Rockwell International and operated by NASA. Named after the commanding ship of a nineteenth-century scientific expedition that traveled the world, Challenger was the second Space Shuttle orbiter to fly into space after Columbia, and launched on its maiden flight in April 1983. It was destroyed in January 1986 soon after launch in an accident that killed all seven crewmembers aboard. Initially manufactured as a test article not intended for spaceflight, it was utilized for ground testing of the Space Shuttle orbiter's structural design. However, after NASA found that their original plan to upgrade Enterprise for spaceflight would be more expensive than upgrading Challenger, the orbiter was pressed into operational service in the Space Shuttle program. Lessons learned from the first orbital flights of Columbia led to Challenger ' s design possessing fewer thermal protection system tiles and a lighter fuselage and wings. This led to it being 1,000 kilograms (2,200 pounds) lighter than Columbia, though still 2,600 kilograms (5,700 pounds) heavier than Discovery.

During its three years of operation, Challenger was flown on ten missions in the Space Shuttle program, spending over 62 days in space and completing almost 1,000 orbits around Earth. Following its maiden flight, Challenger supplanted Columbia as the leader of the Space Shuttle fleet, being the most-flown orbiter during all three years of its operation while Columbia itself was seldom used during the same time frame. Challenger was used for numerous civilian satellite launches, such as the first Tracking and Data Relay Satellite, the Palpa B communications satellites, the Long Duration Exposure Facility, and the Earth Radiation Budget Satellite. It was also used as a test bed for the Manned Maneuvering Unit (MMU) and served as the platform to repair the malfunctioning SolarMax telescope. In addition, three consecutive Spacelab missions were conducted with the orbiter in 1985, one of which being the first German crewed spaceflight mission. Passengers carried into orbit by Challenger include the first American female astronaut, the first American female spacewalker, the first African-American astronaut, and the first Canadian astronaut.

On its tenth flight in January 1986, Challenger disintegrated 73 seconds after liftoff, killing the seven-member crew of STS-51-L that included Christa McAuliffe, who would have been the first teacher in space. The Rogers Commission convened shortly afterwards concluded that an O-ring seal in one of Challenger ' s solid rocket boosters failed to contain pressurized burning gas that leaked out of the booster, causing a structural failure of Challenger ' s external tank and the orbiter's subsequent disintegration due to aerodynamic forces. NASA's organizational culture was also scrutinized by the Rogers Commission, and the Space Shuttle program's goal of replacing the United States' expendable launch systems was cast into doubt. The loss of Challenger and its crew led to a broad rescope of the program, and numerous aspects of it – such as launches from Vandenberg, the MMU, and Shuttle-Centaur – were scrapped to improve crew safety Challenger and Atlantis were the only orbiters modified to conduct Shuttle-Centaur launches. The recovered remains of the orbiter are mostly buried in a missile silo located at Cape Canaveral LC-31, though some pieces are on display at the Kennedy Space Center Visitor Complex.


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