Rapid Descent When Lowering Altitude Setting
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I've had this behavior happen a few times, and was wondering if it's a bug, RW behavior, or "pilot error":
Say I'm descending on a fairly complex STAR using LNAV and V/S mode, with A/T. The plane has almost reached my dialed-in altitude setting for a STAR constraint, the V/S value on the MCP has changed from my previously-set V/S speed to blank, and it's starting to level off. If right then I dial a lower altitude for the next STAR constraint, the plane immediately starts to rapidly descend at sometimes over 2300 ft/min. I have to dial back the V/S setting to something more manageable.
Is anyone else able to replicate this? I can post a Youtube video of this if needed.
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It is good practice to allow the aircraft to level off at a preselected altitude before dialling in a new altitude. I don't recall if it's in the 146 or RJ FCOM (or both), but one of them does advise pilots not to adjust the preselected altitude during the altitude acquisition phase.
From the input we've had from pilots, as well as various reference videos online, we find that pilots flying these older aircraft types spend more time thinking about passenger comfort than those flying modern airliners. For example, a lot of RJ videos online show pilots descending in V/S mode and slowly increasing/decreasing the VERT SPEED value rather than using LVL CHG mode. Even a relatively 'modern' looking RJ is a lot more involved than a modern airliner!
Mark - Just Flight
