RNAV, GNSS, GPSS. Your place to discuss all aspects pertaining to Instrument Flying.

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Unread post by CliffSol » Wed Feb 19, 2020 4:32 pm

Can someone enlighten me as to why I cannot get the GS to work on the VNAV let down ? I am using a G500 linked to G430 (WAAS). The nav database is up to date and I can load the RNAV procedure for Rwy 07. However when activated I cannot see any vertical guidance.
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willem nieuwenhuis
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Unread post by willem nieuwenhuis » Fri Feb 21, 2020 10:05 am

The GPS will check its accuracy constantly and if it can’t guarantee accuracy it will not give you the VNAV . It should warn you in the MSG field.
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Unread post by Hop Harrigan » Sat Feb 22, 2020 1:45 pm

Hi Cliff,
I’m guessing your 430W doesn’t provide vertical guidance...mine only provides LNAV and I fly the RNAV using ROD manually.
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Unread post by Trent772B » Wed Mar 25, 2020 8:29 pm

1. Your equipment isn’t Baro VNAV capable
2. You Nav Database coding doesn’t have the VNAV portion coded.
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