Close to 100 Falcon 900s are the subject of an Airworthiness Directive requiring revisions to the “abnormal procedures” section of the airplane flight manual and an update of EFIS symbol generators.

The changes to the AFM, which are required to be completed this month, advise the crew to avoid the use of certain EFIS display modes on approach. The FAA said it developed the AD (2004-05-15) after pilots reported that the EFIS would flash or go blank during critical phases of flight.

In addition to revising the AFM, the AD requires replacing certain EFIS symbol generators within 18 months. The FAA said affected airplanes include Falcon 900s with S/Ns 1 through 168 and 170 through 178, all of which are equipped with Honeywell SPZ-8000 avionics. Estimated time to complete the work is two hours.