Marshall Space Flight Center Arm Farm

This page is under construction

Test_AreaGraphic_GroundSupport.wmv has some artist concept

Saturn I:

spn Vol 14 No 6 - 20-03-75.pdf 'Arm Farm' Arrives At KSC For Use With Space Shuttle A large part of the "arm farm," a facility used at the MarshallSpace Flight Center, Huntsville, Ala., to test the swing arms for the Saturn V/IB mobile launchers, arrived at KSC this week. The 300 tons of equipment arrived aboard the NASA barge "LittIe Lake" , after a tow across the Gulf of Mexico and up the Florida east coast by the KSC tug "Little Toot." · The test equipment will be pressed into service as key elements in the Launch Equipment Test Facility - to be built south of the Manned Spacecraft Operations Building - to check swing arms and other ground support equipment being built for service during the Space Shuttle era. This launch equipment is expected to be reusable throughout the long span of the Space Shuttle program and will be evaluated for operational reliability and maintainability standards exceeding those of previous programs. It was determined that the most effective and economical way of satisfying shuttle qualification and certification requirements would be the establishment of a permanent Launch Equipment Test Facility (LETF) at KSC. According to Richard Babcock, charged with marine traffic in KSC 's Transportation Services Section , the 300 tons of "arm farm" equipment represents the heaviest cargo ever carried aboard a NASA barge. It arrived here after a four-week, 2,360-mile journey from Huntsville up the Tennessee River to the Ohio River and then down the Mississippi to the New Orleans area. It was picked up at the Marshall Space Flight Center's Michoud Assembly Facility -near New Orleans -by the KSC tugboat for the tow to Florida. After reaching Port Canaveral, it was brought through the locks and up the Banana River to the dock south of the Vehicle Assembly Building. According to Sidney L. Hodge, Jr., of the Ground Systems Project Office in the KSC Shuttle Projects Office, the Apollo equipment to be adapted to the Space Shuttle test role includes three vehicle motion simulators with associated equipment. Among the critical Space Shuttle launch equipment to be tested are the Orbiter Access Arm, Orbiter Tail Service Masts and the External Tank Umbilical, which are separated at ignition; the Midbody Umbilical and its equipment ; and the Solid Rocket Booster Holddown and Support Arms. Use of the Marshall equipment at KSC represents considerable savings through the salvage of otherwise idle equipment and elimination of the need to transport bulky, heavy launch equipment between KSC and Alabama for testing and certification . "It's more efficient to do it this way," said Hodge. "It will be handy for everyone. We'll have access to the launch equipment for training and for trouble shooting problems at the pad." The primary objective in establishing the LETF is to provide the capability to qualify and certif critical launch equipment prior to its installation at the launch complex or between launches when its recertification is required. In addition, it will provide the capability to perform development testing of conceptual ground support equipment designs. The testing will be performed under conditions simulating vehicle motion prior to launch, simulated liftoff, environmental conditions such as rain, fueling, purging, emergency, hold and other situations covered in Shuttl launch operations.

1963/1963_November 20, 1963_47.pdf: TWO SATURN V TEST FACILITY CONTRACTS LET Contracts for building two vital Saturn V testing facilities were awarded recently by the Marshall Center. The facilities will be used to test wing-arms-assemblies connecting the 350-foot tall Saturn V to its launch umbilical towerand hydraulic systems. Sullivan, Long and Hagerty Construction Co., Birmingham, was awarded a $2,194,00 contract for building the Saturn V Ground Support Equipment Test Facility. The Test Laboratory site will be used to test swing-arms which serve as structural supports for servicing lines linking the moonbound rocket to the Cape Canaveral ground support equipment. These arms swing free at liftoff, breaking service connections. The equipment will simulate the breaking of service connections at liftoff in mechanically-made winds of up to 75 miles an hour. All swing arms used to service the Saturn V will be tested at the Marshall facility before being shipped to the Cape Canaveral launch site. Rentenbach Engineering CO., Knoxville, Tenn., will build a Hydraulic Test Facility under a $314,200 contract. Hydraulic systems and components for future launch vehicles and engines will be tested and assembled there. The 45 by 100 foot concrete block building, located in the Propulsion and Vehicle Engineering Laboratory area, will contain a testing area, hydraulic component cleaning equipment and an engineering area. Equipment in the test area will include a hydraulic component test console and launch and vehicle simulators. Components cleaning area will be used to test, inspect, and assemble close tolerance components which are highly sensitive to contamination. The structure will be Building 4618.

1966/1966_June 8, 1966_23.pdf A Bit Of The 'Spaceport' Has Been Created Here A bit of the "spaceport" at the NASA-Kennedy Space Center has been created at the Marshall Center's unique Ground Support Equipment Test Facility where giant mechanical arms which connect the Apollo/Saturn V to launch facilities are tested. The "swing arms" are subjected to tortuous tests as special equipment simulates on cue such conditions as rockets swaying in the wind, freezing rain and hurricane force gales. How well Marshall Center personnel do their jobs in testing the arms will be evident when the first Saturn V launch vehicle leaves its pad at Launch Complex 39 next year. Nine arms, built by Hayes International of Birmingham, Ala., will carry service lines to the 365 foot tall rocket/spacecraft combination as it stands erect on the mobile launcher. These lines are electrical, propellant, hydraulic and pneumatic. Weighing up to 52,000 pounds each, the arms are hinged to the launch umbilical tower. Longest of the devices is 85 feet. Swing arms, so called because they retract as the launch vehicle leaves the ground, also serve as access routes and work platforms for technicians making last minute changes and repairs to the spacebound rocket. Winds up to 75 miles an hour are whipped up here to duplicate Florida storms. The high winds are created by four aircraft engines. Guy Perry, chief of the test facility, said winds may cause the Apollo/Saturn V rocket to oscillate as much as 40 inches. These motions, combined with rain frozen by super-cold propellants, are expected to cause equipment problems. Every arm is put through a series of tests, Perry said, designed to duplicate conditions expected at the launch site. Perry said the 18-acre facility has eight swing arm test positions and one position for testing access arms to be used by Apollo astronauts. Also being tested here are launcher holddown arms and tail service masts. All the tests may be controlled from a central blockhouse. Each test position, Perry said, has two elements - a vehicle simulator for duplicating motions during countdown and launch, and a section duplicating the launch tower. The vehicle simulator duplicates the portion of the rocket skin containing the umbilical connections and personnel access hatches. Driven by a hydraulic servo system, the vehicle simulator produces relative motion between the vehicle and the tower. The simulator can duplicate the motion of any part of the vehicle. Perry said the top of the 36-story vehicle may oscillate up to plus or minus 20 inches at low frequencies - from .2 to 1 cycle per second. Perry said five of the simulators are equipped with elevators that duplicate the lift-off of the vehicle. The elevators move upward for about eight feet to simulate the "breaking" of the umbilical connections at lift-off. Tower simulators duplicate that portion of the umbilical tower where the umbilical swing arm and the equipment required to retract the arms during launch are located. A remote control water spray system is mounted on top of each tower simulator to provide "rain" and for fire protection. Cryogenic liquids are pumped through the lines at five positions to give technicians a realistic look at the equipment after it has been "chilled down." The 29 service arms and associated equipment being fabricated by Hayes are trucked to the Marshall Center for testing and then flown to the Kennedy Space Center. The Super Guppy aircraft, called the world's largest plane, flies the devices to Florida.

1966/1966_March 2, 1966_9.pdf Poseidon carried 3 swing arms on one particular trip from MSFC to KSC, along with the SA-203 nosecone and 500F's IU.

1966/1966_March 9, 1966_10.pdf Guppy flew a swing arm from Birmingham to KSC.

1966/1966_October 19, 1966_42.pdf 'SWING ARMS' FOR SATURN V ARRIVE AT KSC Giant "swing arms" that will provide electrical, pneumatic and propellant service to the Apollo/Saturn V rocket during the launch preparation phase have been delivered to the Kennedy Space Center. Nine of the arms, each weighing between 15 and 25 tons, will be required for each Apollo Saturn V launch umbilical tower. They were designed by KSC and produced under a contract with Hayes Illternational Corp., of Birmingham. A set for the first Apollo Saturn V, to be launched next year, was checked out at the Marshall Center here and delivered this month lo KSC. Four of the nine to be used on the second Apollo/Saturn V launch position left MSFC recently aboard the barge Promise. Two swing arms service the 7.5 million pound thrust first stage. Three are used on the second, or middle, stage; two on the third stage; one on the Apollo service module and one on the Apollo command module near the top of the 365-foot tall vehicle. Shortly after ignition, the arms disconnect and swing away from the rocket as it slowly starts a journey into space. As they swing away, huge alligator-looking jaws clamp shut to protect the connections at the end of the arms from the hot blast of the rocket exhaust as it streaks skyward.

1967/August 2, 1967.PDF Modified Apollo Access Arm Test Program Begins When the first three Apollo astronauts walk along the grated access arm that leads to the entrance of their command module, their "boardwalk" will carry a seal of approval from the Marshall Center. This week the Marshall Center's Test Laboratory will begin a testing program to qualify a newly modified access arm for use with the redesigned Apollo command module. The work is being done for the Kennedy Space Center. The spacecraft has been fitted with a larger, quick-opening hatch that required modification of the astronaut cleanroom that sits at the end of the access arm. The cleanroom, final stopping point for the astronauts before entering the spacecraft, is attached to the command module by a hood that covers the hatch. The sealed connection provides a complete walkway along the access arm, through the cleanroom and into the spacecraft. "Because of the larger hatch, a larger cleanroom hood had to be redesigned," said Jim Stuart, project engineer for the test program. A crew of Chrysler and NASA engineers and technicians will be verifying the fit of the new hood to the new spacecraft hatch. Quick Escape Also being evaluated is an access arm parking brake that furnishes a quicker means for the crew to evacuate the spacecraft. "In the earlier abort escape routine, the access arm would have to swing 120-degrees from its retracted position next to the tower back to the spacecraft to pick up the astronauts as they opened the hatch," said Stuart, adding, "That took about 30 seconds." "Now," he said, "when the crew is deposited in the spacecraft, the access arm only swings back about 12 degrees from the vehicle and parks. If an abort prior to launch is necessary, the arm can be back in position in about eight seconds - not much more than the time it takes to blow the quick open hatch." Modifications Several other minor modifications like coupling mechanisms and redundant valves will also be qualified during the testing program. For testing purposes, a real spacecraft will not be used, but a cork-coated model with the latest design changes will be employed. It simulates bhe portion of the spacecraft in which the exit hatch is located. To exercise the access arm, the dummy spacecraft sits on a motion simulator that can reproduce any mwement the Uprated Saturn I or Saturn V might make while resting on the launch pad (they can oscillate as much as a foot or more in any direction while awaiting launch). The swing arm must be guided to the moving craft for the automatic sealing of the cleanroom and the spacecraft hatch. Four powerful aircraft engines are often used to simulate winds as high as 70 miles-an-hour that might be encountered at the launch site. Prototype The Uprated Saturn I access arm about to be tested is a prototype. The first flight version is to received in mid-September, tested and returned to the Kennedy Space Center by early October. "Every swing arm ever erected with a Saturn vehicle has been rigorously tested here," commented Stuart. Uprated Saturn I vehicles have six arms, each from 25 to 35 feet long and weighing about 5,000 pounds. Only the top swing arm provides access to the spacecraft through a cleanroom. Others, which start near the bottom of the launch vehicle, are about 30 feet apart and have umbilical connections to the aluminum skin of the vehicle that feed propellants, electrical, hydraulic and pneumatic power to the Saturn before swinging away as the vehicle lifts off. The massive Saturn V has nine swing arms, again with only the top one providing access to the spacecraft. Saturn V arms range from 40 to 70 feet long and weigh from 20,000 to 50,000 pounds. They can swing back from the vehicle at launch in five seconds. 9 Swing Arms Each of the three mobile launchers built for the Saturn V will have a set of nine swing arms. The third set is being tested here now and will be shipped to Florida for installation on a launcher. Although the Marshall Center is a launch vehicle development facility and not a launch port, it's still very much in the "swing" of things.

1968/1968_July 17, 1968_29.pdf Huge Swing Arms undergo Checks At Test Lab The Boeing Company and the Marshall Center's Test Laboratory are cooperating on the test and checkout of huge swing arms that will be used at the Kennedy Space Center during the launch of the first manned Apollo Saturn V space vehicle. Nine service arms and three tail service masts are used to provide access to the Saturn V vehicle on the launch pad, as well as to provide a means for supporting all service lines carrying cryogenic fluids, pneumatic, hydraulic and electrical power necessary for checkout, countdown and launch of the vehicle. The Apollo/Saturn 503 access arm testing involves both MSFC and KSC as well as Boeing and Chrysler Corp. This test is slated to be completed in mid-August. Other service arms are being modified and refurbished by Boeing, under contract to the Kennedy Center, in MSFC's Test Lab. Two service arms are complete and work is underway on a third. Five of these service arms and the tail service masts are "fly away" arms that are separated from the vehicle upon lift-off. The other four arms are disconnected during various stages of the countdown. The Marshall Center's Test Lab conducted swing arm tests on equipment used in connection with the successful launch of the first two Apollo/Saturn V rockets.

http://history.nasa.gov/SP-350/ch-3-6.html The connections between the ground and the towering space vehicle posed a tricky problem. An umbilical tower, even higher than the vehicle itself, was required to support an array of swingarms that at various levels would carry the cables and the pneumatic, fueling, and venting lines to the rocket stages and to the spacecraft. The swingarms had to be in place during final countdown, but in the last moments they had to be turned out of the way to permit the rocket to rise. There was always the possibility, however, of some trouble after the swingarms had been disconnected. For instance, the holddown mechanism would release the rocket only after all five engines of the first stage produced full power. lf this condition was not attained within a few seconds, all engines would shut down. In such a situation, unless special provisions were made for reattachment of some swingarms, Launch Control would be unable to "safe" the vehicle and remove the flight crew from its precarious perch atop a potential bomb.

These considerations led to the establishment, at Marshall, of a special Swingarm Test Facility, where detachment and reconnection of various arms was tested under brutally realistic conditions. On the "Arm Farm" extreme conditions (such as a launch scrub during an approaching Florida thunderstorm) could be simulated. Artificial rain was blown by aircraft propellers against the swingarms and their interconnect plugs, while the vehicle portion was moved back and forth, left and right, simulating the swaying motions that the towering rocket would display during a storm.

Click image for a 2807x2235 pixel version of this image in a new window.
Scan courtesy Marshall Space Flight Center.
Clean-up by heroicrelics.org.

More formally, this is the "Saturn V G.S.E. Test Facility, Umbilical Tower Simulators, General Plan" (MSFC drawing number FE-A-4646-T2). This drawing was originally dated July 17, 1963 and updated June 16, 1964 to add the Command Module Tower Simulator to contract.

Click image for a 2048x1434 pixel version of this image in a new window
or click here for a 16000x12000 pixel version.
Scan courtesy Marshall Space Flight Center.
Clean-up by heroicrelics.org.

Marking up the photo above with information from the drawing, we have

Click image for a 2807x1509 pixel version of this image in a new window.
Scan courtesy Marshall Space Flight Center.
Clean-up and labels by heroicrelics.org.

Although it did not appear on the drawing from which I took these labels, it appears that there was also a test position for the Tail Service Mast (in the upper right of this photo). The TSM is of the "clam shell" type, which was replaced with the "roll top desk" type after the launch of Apollo 4 (since the clam shells were blown off the TSMs by the F-1 engine exhaust), which would seem to further date this photo to 1967 at the latest.

Clockwise from the upper left, the swing arms are

S-II Aft Swing Arm 3	Provides access to vehicle. Retracted prior to liftoff as required.
Command Module Egress Swing Arm 9	Provides access to spacecraft through environment chamber. Arm controlled from LCC. Retracted prior to liftoff to a 12° park position until T-4 minutes, when it is fully retracted.
Service Module Swing Arm 8	Provides air-conditioning, vent line, coolant, electrical, and pneumatic interfaces. Retracted at liftoff. Retract time 9.0 seconds.
S-IC Forward Swing Arm 2	Provides pneumatic, electrical, and air-conditioning interfaces. Retracted at T-16.2 seconds. Retract time 8 seconds.
S-IVB Aft Swing Arm 6	Provides LH₂ and LOX transfer, electrical, pneumatic, and air-conditioning interfaces. Retracted at liftoff. Retract time 7.7 seconds.
S-II Intermediate Swing Arm 4	Provides LH₂ and LOX transfer, vent line, pneumatic, instrument cooling, electrical, and air-conditioning interface. Retracted at liftoff. Retract time 6.4 seconds.
S-IC Intertank Swing Arm 1	Provides LOX fill and drain. Arm may be reconnected to vehicle from LCC. Retracted prior to liftoff. Retract time 8 seconds. Reconnect time 5 minutes.
S-II Forward Swing Arm 5	Provides GH₂ vent, electrical, and pneumatic interfaces. Retracted at liftoff. Retract time 7.4 seconds.
S-IVB Forward Swing Arm 7	Provides fuel tank vent, electrical, pneumatic, air-conditioning, and preflight conditioning interfaces. Retracted at liftoff. Retract time 8.4 seconds.

http://history.msfc.nasa.gov/saturn_apollo/farm.html Envision the scene -- the director gives the cue -- huge towering structures sway back and forth blasted by torrential rains and hurricane force gales.

One generation might imagine a scene created by Cecil B. DeMille. Another might think of Steven Spielberg.

Not many would think of a back lot at the Marshall Space Flight Center in the mid-1960s, a site that Center Director Dr. Wernher von Braun and his employees called the "Arm Farm."

Today thousands know the Center for its role in developing the huge Saturn rockets that lifted humans to the surface of the moon in the late 1960s. Some also know about the unique facilities the Center developed to handle the task of testing, building, and launching the Saturn V. The Arm Farm, officially known as the Random Motion/ Lift-Off Simulator was one of those unique facilities.

In addition to designing the actual Saturn V vehicle that would carry humans into space, engineers at Marshall had to make sure that the space-bound vehicle would safely and quickly disconnect from a complex array of service cables and feed lines carrying electrical power, propellant, and other elements.

These cables and propellant lines were supported by giant mechanical arms weighing up to 52,000 pounds each and hinged to an umbilical tower taller than the Saturn V vehicle itself. The arms also served as access routes and work platforms for technicians making last minute changes and repairs to the rocket.

The swingarms had to be in place during final countdown, but in the last moments before launch they had to be retracted out of the way to permit the rocket to rise. There was always the possibility, however, of some trouble after the swingarms had been disconnected. For instance, the holddown mechanism would release the rocket only after all five engines of the first stage produced full power. If this condition was not attained within a few seconds, all engines would shut down. In such a situation, unless special provisions were made for reattachment of some swingarms, Launch Control technicians would be unable to safe the vehicle and remove the flight crew from its precarious perch atop the Saturn V.

This made it imperative that the swingarm mechanisms be thoroughly tested long before launch day ever arrived. Instead, however, of trying to completely conduct such an aggressive test program on site at the Kennedy Space Center, NASA decided to replicate a portion of the Kennedy Center at Marshall. There the detachment and reconnection of various arms could be tested under brutally realistic conditions.

The 18-acre swingarm facility built at Marshall had more than a half dozen arm test positions and one position for testing access arms used by the Apollo astronauts. On the Arm Farm extreme environmental conditions (such as a launch scrub during an approaching Florida thunderstorm) could be simulated.

Each test position had two elements -- a vehicle simulator for duplicating motions during countdown and launch, and a section duplicating the launch tower. The vehicle simulator duplicated the portion of the vehicle skin that contained the umbilical connections and personnel access hatches. Driven by a hydraulic servo system, the vehicle simulator produced relative motion between the vehicle and tower.

Some of the simulators were equipped with elevators that duplicated the lift-off of the vehicle. The elevators moved upward for about eight feet to simulate the "breaking" of the umbilical connections at lift-off.

Tower simulators duplicated that portion of the umbilical tower where the umbilical swingarm and the equipment required to retract the arms during launch were located. Cryogenic liquids were pumped through the lines at various positions to give technicians a realistic look at the equipment after it had been chilled down.

Artificial rain was blown by aircraft propellers against the swingarms and their interconnect plugs while the simulated portion of the vehicle was moved back and forth, left and right, simulating the swaying motion that the towering rocket would display during a storm.

Marshall's Alex McCool, a direct participant in the Saturn V program at the Center recalled the critical nature of the testing performed at the Arm Farm. "There was no way in the world we could have flown the Saturn V without this type of ground support equipment and the associated testing," McCool said.

The scenes that the Marshall engineers and technicians created at the Arm Farm were dramatic. But theatrics were completely incidental to the real task of gathering technical and engineering data in advance of the real drama -- launching the mammoth Saturn V launch vehicle from the Kennedy Space Center in Florida.

By 1968, the work of the arm farm was completed, and the area was given over to testing concepts for the Lunar Roving Vehicle (LRV): a Moonbuggy simulator was constructed adjacent to the arm farm. The swing arms were all gone, leaving only the towers and stage simulators (and, if you zoom in on the area between the hold down arm and service module swing arm test positions, you can see the four aircraft engines with propellers used to simulate high winds). The hold down arms also appear to have been relocated to northwest of the S-II forward swing arm position.

The following photo appears to have been taken around the same time, with the Moonbuggy simulator landscape visible at bottom:

Click image for a 1163x901 pixel version of this image in a new window.
Taken from page 93 (p. 103 in the PDF) of the Historical Assessment of Marshall Space Flight Center.
Extraction by heroicrelics.org.

As seen in this Google Maps link, the arm farm has since been repurposed, the towers and several of the support buildings gone, with new buildings erected on the asphalt. Support Buildings No. 1, 2, and 3 are still there, as is the block house (although with a new roof). The areas were Support Building Nos. 4 and 5 were demolished are visible on the north side of the lot, and what appears to be the foundations for several towers are also visible on the asphalt.

Swing arm descriptions above taken from Technical Information Summary, Apollo 11 (AS-506), pages 18 & 19 (pages 19 & 20 in the PDF).