Recently released documents from the NTSB’s investigation into the crash of a Cessna Citation II (N550BP) that plunged into Lake Michigan on June 4 last year, killing all six people aboard, reveal that a control-wheel electrical cable had not been replaced, as per a 1992 Service Bulletin from the OEM. The NTSB documents also list seven instances of reported failure in other aircraft due to the faulty cable, but the factual report doesn’t single out the cause of the crash of N550BP.