Modern_fm_only not set in some of the new aircraft

Are you using Developer Mode or made changes in it?

Have you disabled/removed all your mods and addons?

Brief description of the issue:

Several users report that some new aircraft are “unflyable” while all the other aircraft work normally (namely in the threads of the LS8 and the Cabri G2 For these users, setting the flight model to “modern” (or cycling through legacy and back to modern) solves the issue.

I looked at the flight_model.cfg files and found that the parameter “modern_fm_only” is not set in some of them (which forces the modern flight model regardless of the menu setting of the user).

The problems with modern vs. legacy flight model are a constant pitas since release of MSFS. I suggest two things:

  1. explicitly set the parameter modern_fm_only=1 in the new aircraft
  2. change the default value of this parameter to 1 instead of 0 so that the modern flight model is used even if it is not set explicitly. At this point, ported aircraft from older versions of MSFS that require the legacy flight model are nearly without any relevance. If someone really uses such an antique, they can set legacy_fm_only=1 in the flight_model.cfg to force the legacy model.

Edit: I just saw in the Cabri G2 thread, that some users report, that the aircraft becomes flyable as soon as they set the flight model to legacy. This does not make sense but maybe this is a hint to the root cause of the problem why some people have problems even when they are on modern flight model in the menu setting. It seems that this setting is flawed and sometimes internally the exact opposite is set (meaning the people changing to legacy actually change to modern). This would also explain why cycling through the setting from modern to legacy and back to modern also solves the problem. This seems to sync the displayed setting back to the actual internal setting.

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