Value chain · CLM-0972
In plain terms
If you take a 1975 estimate of how fast people could build structure in space, checked against one Skylab task, and apply it to the 1978 design's framework, you get a crew of a few hundred to build it in six months, which is roughly what the design said. For the framework, the 1978 numbers add up.
The claim as recorded
Applying the 1975 Raytheon study's Skylab-calibrated assembly rate of 6 to 12 kg per man-hour to the 1978 Reference System's primary and secondary structure mass of 4.96 to 5.89 million kg gives 0.41 to 0.98 million man-hours, which at 6 to 10 productive hours per crew-day is a crew of 226 to 896 for a six-month build. The reference system's published 555 to 715 falls inside that bracket, so its crew figure is consistent with manual assembly of the structure alone.
Evidence behind this: T0-derivation from held inputs, one of them measured (Skylab 3) and the rest 1975-78 analysis.
Scope and limits
STRUCTURE IS ABOUT 10 TO 17 PER CENT OF SATELLITE MASS. THIS SAYS NOTHING ABOUT THE REST, WHICH IS CLM-0973. The one measured datum is a sunshade pole, not a structural member.
What it assumes
6 to 10 productive hours per crew-day, ASSUMED. The rate is calibrated to terrestrial steelwork per p.188 ("in line with that assumed during Task 1, 11 lb/m-hr", the rate at which steel workers construct a major building) and to one Skylab datum per p.175.
Where it comes from
This is the project's own working, shown in full:
Vol III p.188, with the text layer's faults shown: "The overall structure can be assembled at a rate of 13 to 26 lb/m-hr (6 to 12 Kg/m-hr). This range of cost was established by determining the number of Joints in a t}_tca] 105m x 108m primary/secondary structural bay (394)". SRC-085 Table 1 printed p.48, columns GaAlAs then silicon: primary structure 4.172 / 3.388, secondary 0.581 / 0.436 (array); antenna primary 0.250 and secondary 0.786; interface primary 0.094 and secondary 0.003; millions of kg. 394 joints at p.175's 6.2 minutes is 40.7 man-hours per bay, implying 244 to 489 kg per bay at the stated rate, so the two pages cohere. Arithmetic in CALC-113 section 2.
Basis: man-hours; crew for a six-month build
Related records
- Answers question
- QST-015 not published in this release
Cite this
energyaperture.com/c/clm-0972
CLM-0972, Energy Aperture, as of 2026-09-17.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-085
- CLM-0013The paper that modern UK studies rely on for the beam figure calls anything below 1 kilowatt per square metre safe, with 230 watts per...CLM-0020The original 1978 design set the beam at 230 watts per square metre in the middle of the receiving site, about one twenty-third of that at...CLM-0023In the 1978 reference design, two limits set the size of the transmitter and the receiving site: how much heat the transmitter can shed...CLM-0039The 1978 report set the figure to protect radio and navigation systems from a disturbed ionosphere, called the number theoretical and...CLM-0045The apparent conflict between 12 and 23 was not an error. The underlying study gave a range, and the figure adopted sits near the top of it.CLM-0101The 1978 contract required the researchers to report fixes if ionospheric disturbance pushed the pilot-beam phase error past 2 to 3...CLM-0137In four major space solar power studies from 1978 to 2007, none put a number on how much of the beam's energy would be lost if the beam...CLM-0138The original 1978 government design for beaming power down from space adds up all the expected energy losses to get 63% overall efficiency...More on the source page.
- Also from SRC-451
- CLM-0954The 1975 designers worked out how much their kilometre-wide antenna would bend, precisely so they could decide how good the beam-steering...CLM-0959The original 1975 calculation found the satellite's radio noise would be fine for ordinary and troposcatter radio links and a problem only...CLM-0960The 1975 study found the satellite's harmonics - the multiples of its transmit frequency - would trouble radio astronomy at the second and...CLM-0961Everything in the 1975 interference analysis is for one satellite. The study itself says that a hundred of them would raise the noise and...CLM-0965In 1973 an astronaut on Skylab put together two long poles from short sections in just over two hours, about six minutes per join. A 1975...CLM-0966In 1975 the antenna alone was expected to take one to two years to assemble in orbit with about fifty people, and robot arms were judged...CLM-0968The 1975 antenna study worked out how hot the middle of the transmitter gets depending on how efficient the tubes are and how tightly they...CLM-0969If the tubes are only 70 per cent efficient, the transmitter's own face is not big enough to get rid of the heat they make, even spread...More on the source page.