Flight Dynamics Bug Details

Dear Flight Sim Community.

As part of the recent World Update 3, we have inadvertently introduced an issue that is negatively affecting the flaps simulation. The problem was caused by a mistake in the build process, which integrated some incomplete improvements to the flight model into the latest update.

The result is that the lift effect for the flaps (as defined in the flight_model.cfg) is doubled. This only affects the lift of flaps and not the drag, and can be best observed in flap configurations that produce a lot of lift, typically in the landing configuration. As a result some planes glide too much with flaps, and this will be mostly noticed in late final and when flaring. Ground effect and headwinds exacerbate the issue. As this is not always easy to notice, and because this update was not supposed to be about the flight model, the issue was not caught by our quality teams despite all their efforts to avoid this type of situation.

We debated if we should address this via a hot fix as quickly as possible, but ultimately believe that the better approach is to implement the fix and to then thoroughly test everything for the upcoming Sim Update 3 (coming early March).

In the meantime, a workaround is to go into the flight_model.cfg and divide the flap lift by 2x (there are several possible scalars for that purpose: lift_coef_flaps or lift_scalar).

:exclamation: EDIT/NOTE: Please do not use this workaround unless you feel comfortable with coding. This is just a suggestion until the fix is live. :exclamation:

We genuinely regret and want to apologize for the inconvenience this is causing. We will continue to learn and improve our processes to avoid this type of problem in the future as much as possible.

Sincerely,
The Microsoft Flight Simulator Team

197 Likes
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