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Flight Plan Filter – New to 3.22.0 this option is specifically aimed at those users wanting the easiest way to use a flight plan for their FMC and also to be able to load it into PF3. Whilst PF3 would accept any flight plan if it contained a SID and/or STAR, with many waypoints at a short distance apart, you would have a lot of NOTAM messages and would have to remove the offending waypoints. With this option selected, if you load a flight plan containing a SID and/or STAR PF3 will remove all the SID waypoints (except the exit point) and all the STAR waypoints (except the entry point). It will flag (internally) that you have loaded such a flight plan so you will not receive any vectors until you complete your SID (by reaching the assigned altitude of the exit waypoint) and you will be 'Cleared to Final' when reaching the last waypoint (the STAR entry point)

In addition to the above you can also load a flight plan containing no procedures at all when this Flight Plan Filter option is selected and in that scenario PF3 will again enter your cruise altitude in the first waypoint and all those waypoints up to and including your original flight plan's TOD. The descent profile will remain unchanged. When using such a flight plan (with no SID/STAR) you will be able to adjust your altitudes as you can now.

This feature will only work with a valid flight plan. Basically that means it should be in XML format and each waypoint should have a valid altitude, so default FS9 or FSX flight plans would not be valid. The former as it's not XML and the later as the XML file does not include waypoint altitudes. P3D, MSFS, SimBrief and Little Nav Map (to name but a few) all produce such flight plans.