From late 1968 through the spring of 1970 , the Black Knights of HS - 4 participated in .
From late 1968 through the spring of 1970 , the Black Knights of HS - 4 pioneered techniques for the Apollo capsule recoveries .
From late 1968 through the spring of 1970 , the Black Knights of HS - 4 participated in and pioneered techniques for the Apollo capsule recoveries .