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in the future, some of them strong.

The frequency of these is not

presently known, but it is the writer's guess that the risk of a strong earthquake during the next three decades is less than it is in Los Angeles. Likewise, his guess is that the risk of severe damage from earthquakes at South Point is less than the risk of severe damage from hurricanes in Florida, or from tornados in the Midwest.

Although the annual rainfall on the eastern slope of Mauna Loa exceeds 200 inches in some regions, and is generally great, almost all of it soaks into the porous lava soil, and does not reappear in surface springs or streams. It must, therefore, form a subsurface water table, which must extend under the ocean, to form submarine springs. Studies show that several million gallons per day could be pumped from the water table near sea level on the eastern side of the South Point peninsula. Recent experiments with airborne infra-red scanners reveal the underground water by its cooling effect on the surface rocks and soil.

There is almost no population within 10 miles of South Point. Naalehu and Waiohinu, 12 miles away, have a population of about 1000, together. There are large herds of fine Hereford cattle grazing on the lush pasture land within a few miles of the point, mainly owned by a single company leasing the land. At and beyond the villages just mentioned is some of the most beautiful and pleasant territory for homes to be found anywhere. However, there is very little population outside these villages within a radius of 35 miles. Sixteen miles from South Point, beyond Naalehu, is a sugar mill, and there are sugar plantations.

The launch structures would be located along the base of the 500-ft. cliff. Newly assembled rockets and nose cones would be transported on a ground effect machine from the assembly plant near Naalehu. All rockets would be returned from all practice and operational flights to the launch structures by means of retrothrust from vertical launches. The cliff would provide access to the nose cones on the rockets, and would facilitate replacement of expended

nose cones.

The vendor-owned propellant factory would be located

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on the cliff. It would manufacture hydrogen gas from methane shipped from the continent in the liquid state. By-product carbon monoxide and additional methane would be burned to power gas turbines to drive the compressors, which would be used in the liquifaction of the hydrogen, as well as of oxygen from the air. Some liquid nitrogen would be produced for the cryogenic stretch-forming of rocket propellant tanks at the assembly plant. At a mixture ratio of 5.5, the cost of hydrogen and oxygen, including taxes, plant, amortization, profits, and propellant losses, is expected to be 5 cents per pound, in the rockets.

A minimum of fabrication would be done at the assembly plant. The larger propellant tanks would be welded from sheet metal, and cryogenically stretch-formed at the assembly plant. Smaller tanks would be purchased on the mainland, and cryogenically stretch-formed at the assembly plant. Practically all other components would be purchased already assembled, and transported to the assembly plant. It might even be possible to fabricate the larger tanks on the mainland. Standardized parts would facilitate assembly and checkout.

The delivery rate for launch ɛtages cannot be specified in advance. It will be necessary to acquire a fleet capable of making over 200 launches per year of various kinds, irregularly distributed in time. In addition, it will be necessary to replace accidental losses and retirements. Neither of these is predictable in advance, although it seems reasonable to expect that after the early years each launch rocket will on the average survive at least 100 launches. A capacity of four units per year, operated at two units per year, may be about the right size.

The check list of missions, Table 4.2, gives a working estimate of the number of nose cone assemblies expended per year. The production rate is summarized below, in Table 6.3.4. The number of pumps, each supporting 200,000 lbs of thrust, for the launch and upper stages, is 766 per year. The number of pumps for the 50,000 lbs thrust stages is 154.

The cost of the proposed program will be mainly one of human
It will include some material resources, such as factory

effort.

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facilities, office buildings, land, a few thousand tons of iron and aluminum, a fraction of one percent of the production of methane,

and a few other odds and ends, but by far the greater part of the cost will be salaries and wages. The cost can only be measured in dollars. In actual fact it is labor. The distinction is important, for it enables us to schedule expenditures in accordance with the well known characteristics of population growth curves.

Bar graphs are sometimes used to schedule the beginnings and endings of a set of interdependent tasks. Actually, each bar should be replaced by a population growth curve, showing the incubation, youth, maturity, decline, and death of the particular payroll represented. When the superposed growth curves are added together, they should give a combined population growth curve which is free from peaks and dips. If peaks and dips are present, they can be eliminated by rescheduling. A schedule thus rationalized beforehand is prerecuisite for efficient utilization of employees, and for predicting costs. It is an effective management tool, since

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the slightest departure up or down from the schedule can be immediately detected abd corrected.

Figure 6.3.2 shows in a generalized way the cost of a large, complex undertaking plotted against time to completion. Point 1 corresponds to minimum cost, and Point 2 to minimum time. The problem, of course, is to plot the curve accurately, especially before the undertaking is started. Point 2 corresponds to a "crash" program, which is a fair, descriptive title for the APOLLO moon program. In order to meet the schedules, back-up programs must be funded, organizations must be over-staffed, and excessive expediting is required. Small errors in predicting the plotted curve result in large over-runs in cost, and at least some over-run in time. Point 1, on the other hand, is much less sensitive to errors in prediction. Some urgent requirement, such as a military emergency, may dictate selection of Point 2. A solar-exploration program is best planned at Point 1. A subjective estimate is that the selection of Point 1 for a future program will reduce costs at least twofold compared with the selection of Point 2.

An exact cost prediction for the proposed program is yet to be completed. However, there are several important factors which, will make the cost less than people have learned to expect. The first of these is job experience. Assuming that the nation continues space exploration, the most important benefit of space expenditures to date will have been, not the landing of men on the moon, or the sending of spacecraft into interplanetary space, rewarding as these feats may be, but the creation of a national reservoir of skills and knowledge which can be applied to a future program. Another factor is the proposed recovery of all launch rockets, and the standardization of launch rockets, space rockets, spacecraft, and operations. A third factor is the proposed use of the new facilities, rockets, and organization for many missions over a period of many years. Ultimately, of course, we can expect to see the proposed plan become obsolete, but the usual time constants for innovation in space rocketry are measured in decades, owing to the length of time it takes to replace established teams with young people not committed to the old ways of doing things. A fourth factor is

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Fig. 6.3.2 COST VERSUS COMPLETION TIME OF A COMPLEX PROJECT

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