June 23, 2020
In 2017, Rockwell Collins, Inc., (now part of Collins Aerospace) issued an Operators Service Bulletin regarding an FMS issue that can arise when a “Climb To” altitude is edited manually or by using the temperature compensation (temp comp) feature at a specific set of airports under certain conditions.
Recently, the FAA published Airworthiness Directive (AD) 2020-10-05, which is effective June 24, 2020. The AD is applicable to Pro Line 4 and 21-equipped aircraft with FMS 3.3X through 4.X and addresses the temp comp FMS issue.
The AD requires OEMs to update relevant aircraft flight manuals, and operators to disable the FMS temp comp function no later than June 24, 2021. If temp comp calculations are necessary, the operator must make these calculations manually. Operators must also refrain from manually editing “Climb To” altitude on both departures and missed approaches.
Collins recently gave notice to owners and operators who are subscribed to the affected navigation database and released two service information letters, explaining how to modify affected aircraft. The company recommends owners and operators have their aircraft modified at their next scheduled maintenance events, but no later than June 24, 2021, to ensure compliance with the AD.
“NBAA has been monitoring this situation since 2017,” said Doug Carr, NBAA’s vice president of regulatory and international affairs. “This AD should put to rest an issue that affected thousands of aircraft.”
Owners and operators of affected aircraft should contact the Collins Customer Support team with questions. They may be contacted at: AvionicsSupport@collins.com or (319) 295-5000.