The Crawler Makes Its Debut

On Lincoln's birthday, 1962, an LOD team visited Paradise, Kentucky, to watch a Bucyrus-Erie 2,700-metric-ton crawler-shovel in action. Albert Zeiler's report compared the crawler favorably to LC-34's service structure. The work platform, stabilized by hydraulic cylinders at the four corners, varied no more than one-half degree from level. Nearby, Bucyrus-Erie was constructing for the Peabody Coal Company a larger crawler-shovel which would have a load-bearing capacity in excess of the expected weight of the Saturn C-5 and its support equipment. Although minimum speed for the existing crawler was only 6.1 meters per minute, more speed could be built into the new model. Impressed with the crawler's potential, the LOD representatives asked their hosts to propose a study program for LC-39.27

Bucyrus-Erie began such a study one month later. An LOD phone call on 23 March requested preliminary information for Petrone's congressional briefing that afternoon. Thomas Learmont, Bucyrus-Erie's chief design engineer, provided tentative estimates: the crawler, jacks, hydraulic system, and steering mechanisms would cost $3,650,000, the umbilical tower $1,500,000, the box structure (launch platform) $800,000. The crawler figure reflected the cost of Bucyrus-Erie's new model with few changes. Later Bucyrus-Erie incorporated a redundant power system and a more sensitive leveling mechanism, raising estimates an additional million dollars. Although the crawler's reliability and flexibility were attractive the cost was a major disadvantage. LC-39 plans called for five launcher-transporters, putting the price of the crawler units at nearly $25 million. In early April, Buchanan suggested separating the launcher from its transporter and building only two crawlers. The proposal would increase total launcher-transporter weight (the separate crawler would require a heavy platform), but the cost savings more than compensated. After Buchanan's idea won approval, LOD supplemented Bucyrus-Erie's contract to include a "separate crawler" investigation.28

By May the crawler was scoring the highest marks of the three transfer proposals. On the 10th Poppel, Buchanan, and Duren inspected barge tests at the model basin and reviewed the adverse findings from the wind tunnel. The following day Bucyrus-Erie's final presentation was well received by NASA personnel. The crawler would go 1.6 kilometers per hour under load. Its turning radius was 152 meters. The hydraulic leveling system would keep the platform within 25 centimeters of the horizontal when moving on a 5% grade. The Jacksonville engineering firm of Reynolds, Smith, and Hills reported crawlerway costs per mile of $447,000 on high ground and $1,200,000 across marsh. The latter figure included the cost of removing 6 meters of silt so that a firm roadway could be constructed. The estimate was close to the eventual cost of $7.5 million for ten kilometers of crawlerway, On 15 May, Harvey Pierce summarized Connell's rail study. Although the new railbed appeared sound, it was unproven and twice the cost of a crawlerway. Perhaps more important, the switching arrangements looked like trouble to operations personnel. 29

The crawler received a further boost from a 1 June Corps of Engineers report. During a three-week study, the Jacksonville office focused on Merritt Island's ability to support the different transporters. Rail fared the worst.

As a result of the nonhomogeneity of the foundation materials, differential settlement is inevitable along any long embankment. The effect of such settlement would be most detrimental to any system using rails or concrete slabs. Flexible pavements would be less affected and the effect on canal design would be negligible.30

A barge transporter would entail high construction costs for a launch basin and docking facilities at the vertical assembly building; the Corps of Engineers estimated $20,000,000 for the launch basin alone. The crawler presented no serious problems.

The decision to use the crawler came at an LC-39 conference on 12 - 13 June. Representatives from NASA Headquarters, the Manned Spacecraft Center, Marshall divisions, and private industry joined LOD at the Cape meeting. The launcher-transporter's crucial role placed it first on the agenda. After reviewing LOD's search, Donald Buchanan compared the three major contenders. Although the barge concept offered the best growth potential, there were unresolved design problems with propulsion, steering, platform stability, and placement at the Launch pad. Buchanan noted, "If meeting a tight schedule has any bearing an the choice of modes, it would be difficult to assign a low enough value to the barge to illustrate the situation as it now stands."31 The barge's operational shortcomings included a vulnerability to blast and a slow reaction time (evacuating the rocket in an emergency from the launch pad). While both the rail and crawler systems were within the state of the art, the latter enjoyed advantages of cost and flexibility. Buchanan's crawler recommendation met no serious objections.32

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Plans for a VAB

The complexity of LC-39 planning dictated formal program management. Debus moved to provide this in the summer of 1961 with the establishment of the Heavy Space Vehicle Systems Office. Rocco Petrone and two assistants constituted the primary working force at the outset. J. P. Claybourne, a Minnesota native and New York University graduate, had handled program management with Petrone in the Saturn Systems Office the previous year. William Clearman, raised in Georgia and educated at Georgia Tech, had served with naval aviation during and after World War II. By early 1962 Petrone's office was providing other LOD offices with program criteria: details such as hook height, service platform levels, umbilical tower service arm heights, and weight loads for the transporter. This involved frequent liaison with MSFC, Houston's Manned Spacecraft Center, and NASA Headquarters.33

The vertical assembly building received much of the Heavy Vehicle Office's attention. As Petrone noted in a March 1962 congressional briefing, "the building is our most expensive item. On this item we put forth greatest study."34 At the time Petrone estimated the VAB would cost $129.5 million of a total of $432 million for the entire complex. The earliest plans for the VAB envisioned a circular assembly building with a turntable to position the transporter. An alternate scheme resembled Martin Marietta's Titan II assembly building design with high bays in line. LOD's October 1961 study placed the high bays back-to-back with the transporter routed down the middle of the VAB. Martin's C-3 study proposed a box-shaped VAB in which six high bays enclosed water channels - transportation by barge was still being considered. There were two unattractive features. An extensive canal system within the VAB would hamper operations and raise the humidity. Negotiating right angle turns into the high bays with the barge would require a floor plan of 204 x 303 meters, nearly 50% larger than the eventual VAB. LOD vetoed the design in January 1962.35

At the LC-39 conference 6 February 1962, the Launch Facilities and Support Equipment Office agreed to compare open and enclosed VAB designs. Much of the subsequent study was performed by Brown Engineering Company of Huntsville. Ernest Briel directed 20 men investigating two VAB concepts with a barge transfer: one, a fully enclosed box structure with outward-opening bays; the second, an open, in-line structure with silo vehicle enclosures for the launch vehicle. R. P. Dodd supervised the Brown effort; James Reese performed liaison. Brown's reports on 2 April rated the enclosed VAB good for operating characteristics but poor for expansion potential because of canals on three sides and a low bay on the fourth. With the in-line version, the canal would run along the front side, permitting expansion. Low cost was a second advantage; Brown engineers placed a $65 million price tag on the open VAB, $10 million less than the enclosed version. Since a major reason for the remote assembly building was protection from the weather, operations personnel opposed the open concept. 36

Drawing of possible assembly buildings for C-5. Open version.

The operations group carried the day at the 13 June LC-39 conference. Gruene led the attack against the open design, arguing that environmental control would be a problem because of the umbilical openings; lightning would be a hazard in an open VAB, particularly if a rocket returned from the pad with ordnance aboard; with the silo enclosure open during assembly, high winds could curtail operations; and work at umbilical arm heights would be difficult. The conference agreed to a closed VAB, but no choice was made between an inline and a box design. 37

Drawing of possible assembly buildings for C-5. Closed version.

While selection of the crawler simplified VAB planning, the design remained tentative the rest of the summer. At an 18 June meeting, Deese presented a design of six high bays in line and a low bay to the rear, the high bay areas to be constructed in three increments. The low bay, completely air conditioned, would provide checkout areas and aisle space for the upper stages and spacecraft. After erection of the first stage on a launcher-umbilical unit (accomplished by a 250-ton crane at the barge unloading dock), the crawler would carry it into a high bay through a 43 meter wide door and position the launcher on a set of concrete piers. Mating of the remaining stages would take place in the high bay where five retractable platforms provided access to the rocket. The launch control center and the central instrumentation facility would probably be housed within the VAB, using the roof as an antenna platform. Deese stated that an early definition of requirements was needed for both facilities. 38

VAB design was again discussed at a 31 July meeting convened by Petrone. Hook height for a 60-ton crane to mate the upper stages was set at 139 meters; the door would extend 3 meters higher. The first of four high bays would be ready for use in January 1965. The launch control center would go either on top of the low bay roof or between the transfer portals that opened to the high bays. Matters were still unsettled at a mid-August briefing for the center director. When LOC engineering presented a VAB plan with four enclosed high bays in line, Debus expressed reservations about the number of bays and the in-line design. 39

The architectural-engineering consortium URSAM won the contract for detailed VAB criteria in late August 1962 and quickly went to work. On the 30th, URSAM received a set of documents from the Cape that included: "An Evaluation of an Enclosed in Line Concept of a C-5 Vertical Assembly Building," prepared by Brown Engineering Company; an evaluation of an open concept for the VAB, also prepared by Brown; NASA organizational charts and schedules; a general site plan of the Cape Canaveral missile test area; a "Geology and Soil Report" made by the Corps of Engineers the previous June; configurations of the C-5; plans of the retraction mechanism for the umbilical tower arms; general instructions; and discussions of the function of the VAB. 40

By September a Facilities Vertical Assembly Task Group consisting of Arthur J. Carraway, Jack Bing, and Norman Gerstenzang of NASA, and Wesley Allen and Ernest M. Briel of Brown Engineering, was busy defining requirements for URSAM - the general layout of the VAB, the needed shops, general support engineering, and work areas. Some 600 people were expected to work in the VAB, including 100 Pan American maintenance people. A variety of things had to be resolved, from the requirements for a cafeteria to the umbilical arms in the low bays. On 6 September the group worked out methods of obtaining critical and emergency power; the cable requirements from the pad to the VAB, from the launch control center to each high bay, and within each high bay ; the power requirements for the launcher umbilical tower; and the launch control center layout.41

Four days later an URSAM team arrived at the Cape and, in its first meeting, reached a major decision. It proposed that NASA place the bays in the VAB back-to-back rather than in-line, to gain the following advantages:

• Availability of all four high bays for vehicle erection and assembly without any restrictions.

• Reduction in the number of cranes required from seven to three.

• Elimination of extensive handling of the upper stages on railmounted dollies, thus avoiding complex turntable installations and differential settlement problems.

• Simplification of booster and upper-stage transfer and erection procedures.

• Greater adaptability for expansion.42

Another consideration, the paramount one for many LOD engineers, was the wind load factor. The huge assembly building would be subjected to tremendous wind pressures and a back-to-back design promised more stability. 43

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