Value chain · CLM-0965
In plain terms
In 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 antenna study used that as its only real-world data point for how fast people can build things in space.
The claim as recorded
Raytheon's 1975 MPTS study reports a measured Skylab 3 assembly rate - one astronaut assembled two 55 ft poles in 5 ft sections in 137 minutes, 6.2 minutes per operation - and projects 2.5 minutes per operation with a 90 per cent learning curve. Separately it states a tentative in-orbit fabrication rate of 420 lb/hr for MPTS structural elements, needing eight manufacturing modules to meet the assembly timetable.
Evidence behind this: T3-primary-report carrying a T1 measurement: the Skylab 3 rate is an observed astronaut assembly time, the only measured human assembly rate in the corpus; the 420 lb/hr is modelled and the 2.5 min is a projection.
Scope and limits
THE SKYLAB FIGURE IS THE ONLY MEASURED HUMAN ASSEMBLY RATE IN THE HELD CORPUS AND IT IS A SUNSHADE POLE, NOT A STRUCTURAL MEMBER. The 420 lb/hr is "tentatively established" by an operations analysis, so modelled. The 2.5 min/op is a learning-curve projection. Three different standings in one paragraph; keep them apart.
What it assumes
"rain" is the text layer's rendering of "min" and "MI_rS" of "MPTS"; both transcribed raw, not repaired.
Where it comes from
PDF p.175, raw rendering: "In the Skylab 3 mission, a single man assembled two 55 ft poles in 5 ft sections in 137 minutes. This represents an assembly rate of 6.2 rain/operation. A typical MI_rS 18 meter structural member would require 78 operations. Assuming a 90% learning curv_ improvement in skills relative to Skylab performance, a 2.5 rain/operation could be considered plausible." And: "An operations analysis of this process has tentatively established a rate of assembly of 420 lb/hr for the MPTS structural elements. At this rate, eight manufacturing modules would be required to meet assembly time tables." Arithmetic: two 55 ft poles in 5 ft sections is 22 sections; 137 / 22 = 6.23 min per operation, consistent with the stated 6.2.
Basis: minutes per assembly operation; lb per hour of structure
Related records
- Answers question
- QST-015 not published in this release
Cite this
energyaperture.com/c/clm-0965
CLM-0965, Energy Aperture, as of 1975-12.
Connected records
Other published records linked to this one. A list, not a judgement.
- Also from SRC-451
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