Complex sentence: For example, one engineer suggested that joint rotation would render the secondary O-ring useless, but Hardy did not forward these memos to Thiokol, and the field joints were accepted for flight in 1980.
Split into simpler sentences: For example, one engineer suggested that joint rotation would render the secondary O-ring useless. But Hardy did not forward these memos to Thiokol, and the field joints were accepted for flight in 1980.