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FPM vs ANGLE for descent

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oskrypuch View Drop Down
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    Posted: 25 Apr 2023 at 9:33am
Noticed this option with 10.3, perhaps to support the new VNav, which unfortunately I can't use as it is disabled for non-550 untis.

I normally set a FPM target to chime the TOD gong. I'm wondering if using ANGLE might be better, or perhaps it won't really work, as I don't have VNav available (or set). I presume that both methods take into account the instantaneous winds by using GS, and the difference is just a bit of arithmetic.

Anyone using 10.3 for a while, what do you do?

* Orest


Edited by oskrypuch - 25 Apr 2023 at 10:38am
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Sanjiv View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Sanjiv Quote  Post ReplyReply Direct Link To This Post Posted: 02 May 2023 at 8:29pm
I'll test mine this week. Enroute VNAV enabled in setup menu (not settings)? From user manual it seems that FPM is eventually converted into angle for guidance. (page 6-38)

"When a target vertical speed is specified, the IFD will compute the TOD point using current groundspeed and the desired descent rate. However, when the aircraft reaches the TOD point and enroute VNAV is allowed, the IFD will compute the angle required to reach the desired altitude, then commence with enroute VNAV using that angle. "
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Gring View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Gring Quote  Post ReplyReply Direct Link To This Post Posted: 03 May 2023 at 7:28am
Orest,

After a bit of playing, I went back to a FPM value.  This allows me to set the autopilot, or hand fly with a known target value for vertical speed. 
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MysticCobra View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote MysticCobra Quote  Post ReplyReply Direct Link To This Post Posted: 03 May 2023 at 11:50pm
Does it really matter, if you're using the Boeing Banana as your guidance??  ;-)
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oskrypuch View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote oskrypuch Quote  Post ReplyReply Direct Link To This Post Posted: 06 May 2023 at 9:39pm
The Banana rules!

* Orest

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