Violent Level-off Reengaging VNAV

During my descent, I disengaged VNAV and managed VS manually through a turn since VNAV doesn’t account for the distance reduction by the turn radius. Coming out of the turn, I reengaged VNAV and the VS was reset to zero. The autopilot yanked the nose up and overshot, etc., etc.

Could the devs look into changing the behavior of the autopilot when engaging VNAV so that the VS is initially set to the current VS target rather than zero?

On a related note— sometime in the near future— could the behavior of APPR be modified to allow for nonzero vertical speed glide slope interception? There are many procedures where the glide slope is captured from below at a shallow descent, or even from the same 3-degree descent path. Maybe there’s already feature request for this… 🤔

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I was even going to create a post about this. Seems I’m not the only one bothered. Let me try and describe the problem with an example:

Say you’re descending manually without VNAV, -1500 fpm. You then decide to engage VNAV. Instead of it using -1500 fpm as a sort of baseline from which to either increase or decrease the rate of descent, it jumps upwards as if trying to start at 0 fpm. This causes the nose to pitch up violently. An awful experience indeed.

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The APPR issue as well is why I never use that function.

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I’m also a victim from this situation.

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