Early in 1967 Project Apollo suffered its worst setback when all three members of the first crew to fly in an Apollo spacecraft died in a fire. The tragedy forced a reexamination of the project, especially NASA's supervision of its prime contractors, and delayed the first lunar landing by some unknown length of time.
The fire had no direct effect on the lunar science program other than to provide vitally needed time to catch up to the launch schedule. The experiments package, the selection of landing sites, and the lunar-surface geology program all put the time to good use.