INS Updates There be dragons

[IvanK]

INS Updating .... A personal view

So the procedure to update is to Select a waypoint, fly directly over the waypoint then press the _|_ then press Validate. Easy. However blindly accepting an update can make things worse. Lets say you don't get yourself exactly over the Waypoint or heaven forbid you have the wrong waypoint selected. A blind update just adds to the error. ... then where are you ?

So how to control things a little more.

Firstly Verify the waypoint selected and the visual feature are one in the same.

Then rotate the mode selector to Alg/Along. 

Then when you are over the Wypt hit the _|_ THEN look at the left window in the INS to see the accumulated/perceived error in nautical miles. If it looks reasonable then Validate. If unsure hit CLR to reject the update and exit update mode.

Whats a reasonable error ? judgement required but anything <1nm is probably OK. If its >1 nm CAUTION have a careful think as to why the error is so large if its logical then OK accept the update by hitting the validate key ... if unsure reject the update with the CLR key.

Edited April 15, 2023 by IvanK