CALC-073
Production doublings implied by NASA's own module count
What this is
This is the project's own arithmetic, published in full so it can be checked rather than taken on trust. It is not a source. Every input it uses is cited to a record, and the conclusion it reaches only carries as far as those inputs do.
Feeds CLM-0547. Answers QST-004. Basis: dimensionless (production doublings). The cleanest arithmetic in this half of the catalogue.
Why it was needed. A learning curve is applied per doubling of cumulative output. A learning rate stated without the number of doublings it will be applied over is uninterpretable, and the number of doublings here is the reason CALC-056 found module learning rate to be the single largest lever in the whole sensitivity sweep.
Inputs.
| Quantity | Value | Source | Stated or assumed |
|---|---|---|---|
| RD1 module count over the programme | approximately 1,500,000 | SRC-012 | STATED by NASA |
| RD2 module count over the programme | approximately 2,000,000 | SRC-012 | STATED by NASA |
| That "doublings from a first unit" is the right framing | - | consistent with CLM-0185's own sensitivity and the Wright/Crawford model at CLM-0189 | ASSUMED, with the consistency argument stated |
Working, transcribed.
log2(1,500,000) = 20.52
log2(2,000,000) = 20.93Result: approximately 20.5 to 20.9 successive doublings of cumulative production.
State what a "doubling" is here, because the word carries the whole learning-curve argument. It is a doubling of cumulative units produced, counted from the first unit, not a doubling of production rate and not a doubling per year. Twenty-one doublings is what turns a per-doubling rate difference of ten percentage points - 0.75 against 0.85 - into the 0.442 USD/kWh swing CALC-056 measured, which is larger than driving launch cost from 100 M to 10 M USD per launch.
Conclusion. A simple derivation whose value is entirely in making a scale concrete. Its
conf: HIGH is right: two logarithms of two published integers.
Where this fails. The claim's own limits say it plainly - "a simple arithmetic derivation,
not a new physical or economic finding". It says nothing about whether a learning rate observed
over a few doublings in any industry can be extrapolated over twenty-one, which is the question
that actually matters and which this record does not touch. verified: UNVERIFIED.
Cite this
energyaperture.com/calc/calc-073
CALC-073. The working above, not a source document.