Service Information Letter
SIL Number: 606-00083-012
To: Owners/Operators of Avidyne Release 9-equipped aircraft
Autopilot Behavior in Approach Procedures Containing Holding
Subject:
Patterns in R9 Systems
This Service Information Letter (SIL) advises owners and operators
of Avidyne Entegra Release 9-equipped aircraft that the autopilot
Purpose: (55X or DFC100) may fly the final approach course instead of
remaining in a holding pattern on some RNAV or GPS approach
procedures
Revision: 00 Date: 01/23/2012
Problem Description
This Service Information Letter (SIL) advises owners and operators of Avidyne Entegra Release 9-
equipped aircraft that, due to irregularities in how approach procedures are interpreted, on GPS
approaches with holding patterns at the Final Approach Fix (FAF), the autopilot (S-TEC 55X or DFC100)
will incorrectly fly the final approach segment instead of remaining in the holding pattern as depicted in the
FMS and on the moving map. This issue only occurs when the autopilot of flight director is engaged.
This issue affects GPS approaches, RNAV(GPS) approaches, or approaches with GPS overlay (“or GPS”
in the title) with a holding pattern course reversal at the FAF.
If the aircraft is aligned with the final approach course (within +/- 15 degrees) and the holding pattern
course reversal is the next leg in the flight plan, upon reaching the FAF, the R9 system and autopilot/flight
director will continue towards the Missed Approach Point (MAP) and descend, if applicable, instead of
entering the holding pattern which is depicted on the map. The FMS active leg will not be automatically
sequenced to the final approach leg and will continue to depict the holding pattern as the active leg.
If the aircraft is not aligned with the final approach course, the R9 system and autopilot will correctly enter
the holding pattern prior to proceeding inbound on the FAF to MAP leg. Likewise, if the pilot selects “Skip
Hold”, the holding pattern will be skipped and the aircraft will proceed inbound, descending if applicable,
upon reaching the FAF.
Solution
Pilots are encouraged to closely monitor the R9 system and autopilot during all approaches. If the
autopilot does not follow the desired path, pilots should immediately disconnect the autopilot or switch to
heading mode (HDG) control of the autopilot.
For approaches which contain a holding pattern located at the FAF and the aircraft is arriving at the FAF
lined up with the final approach course, pilots should request a straight-in approach with ATC and select
“Skip Hold” or delete the holding pattern in the R9 system. If the pilot wishes to fly the holding pattern
Revision: 00 606-00083-012
Date: 01/23/2012 Page 1 of 2
Service Information Letter
instead of flying a straight in approach, the pilot should disconnect the autopilot and hand fly the holding
pattern or fly the holding pattern using HDG mode of the autopilot. The autopilot can be coupled using
NAV mode once the aircraft has joined the final approach leg and the pilot wishes to proceed inbound past
the FAF.
Effectivity
Description IFD5000
Avidyne Part Number 700-00083-()
Avidyne Software Release Release 9.0.X, 9.1.X, 9.2.X
All Release 9 software versions to date (9.0.X, 9.1.X, 9.2.X) are affected by this anomaly. The resolution
to this issue will be included in the next R9 software release. The schedule of this release has not been
determined.
Contact Information:
Any customer who experiences the symptoms described above or has additional questions can contact the
Avidyne Entegra Release 9 Hotline.
Avidyne Entegra Release 9 Hotline: 1-877-MyAVIR9 (1-877-692-8479)
For International Customers: 1-781-402-7592
Revision: 00 606-00083-012
Date: 01/23/2012 Page 2 of 2
