SIL 4550-07: Software version 1.09 for ARINC 429 interface option – 11/13/2013
SIL 4550-06: Hardware modification to prevent excessive vibration of slip/skid ball – 6/13/2013
SB 4550-05: Software version 1.07 – 3/14/2011
SB 4550-04: Display discoloration – 8/20/2009
SB 4550-03: Software version 1.06 – 10/31/2008
SB 4550-02: Attitude and radar altimeter test drive output drive current – 8/30/2007
SIL 4550-01: Software version 1.02 – 8/30/2007