Some bugfixes and improvements require aircraft to be adapted/fixed to remain airworthy, to be working correctly, or to be taking full advantage of latest FlightGear version. The following ''Airworthiness Directives'' and ''Aviation Maintenance Alerts'' issued by the ''FlightGear Aviation Administration'' (FAA) should be considered for aircraft maintenance (A/B/C/D checks).
== JSBSim ==
=== Deprecated engine properties "egt_degc" and "egt_degf" ===
Properties will be removed with a future JSBSim/FlightGear version. Replace "_" with "-", i.e. use:
== FlightRecorder ==
The default FlightGear flight recorder matches propeller/piston aircraft only. For >= FG2.6.0 the correct flight recorder configuration file matching the aircraft type should be selected. It is also possible to add custom properties.
== Rating System ==
A new rating system was introduced. Aircraft ratings should be encoded in the aircraft -set.xml file from where they are be picked up by launchers like FGRun, web pages etc
. See [[Formalizing Aircraft Status]].