History1960sUnited Statesmedium confidence

By October 1964, Grumman's lunar module design had grown to 33,000 pounds, up from the original 22,000-pound, two-stage design.

Notes on verification

Multiple independent sources corroborate the general trend of lunar module weight growth from ~22,000 lbs to roughly 30,000-33,000 lbs by late 1964, though exact figures and dates vary slightly (~1,000 lbs, ~1 month) between sources, typical for evolving engineering estimates. [tier=silver indep_score=0.833 clusters=3 claim_tier=notable]

Sources