SA4550 Service Bulletins and Service Information Letters 

To download the latest software for the SA4550 please use the following form: 
Software Update Download

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