From November 1965 to July 1966, Douglas and IBM studied a way of making the S-IVB/IU combination even more useful for lunar exploration. Their concept, which involved soft-landing S-IVB/IUs on the moon, was called Lunar Applications of a Spent S-IVB/IU Stage (LASS). The study team estimated that the first LASS lander might reach the moon in 1970 or 1971.