Classic British Flight Sim

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.

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.

Thank you, sir.