F27 radio stack question

[KellyB]

In Fraser McKay's F-27 panel, in the radio stack the NAV1 radio has two guarded switches called GPWS and G/S.

I can't find anywhere in the documentation what these are for, nor can I determine what happens when they are toggled.

Help, please.

[cowpatz]

They are switches to silence the warnings associated with the ground proximity warning system (GPWS) and when going below glideslope on the ILS (G/S).
These can be used to silence nuisance warnings or to use them for certain Non-normal aircraft configurations used during emergency or abnormal landing situations.

[KellyB]

Thank you, sir.