Would a pilot know that one of their crew is armed?

The Federal Flight Deck Officer page on Wikipedia says this:

Under the FFDO program, flight crew members are authorized to use firearms. A flight crew member may be a pilot, flight engineer or navigator assigned to the flight.

To me, it seems like this would be crucial information for the PIC to know, if their flight engineer (for example) was armed; but on the flip-side of this, the engineer might want to keep that to himself if he's with a crew he hasn't flown with before.

Is there a guideline on whether an FFDO should inform the crew that he's armed?

• It will become rather apparent when you see the crew member unlock, load and holster their weapon. – casey Apr 9 '14 at 21:24
• @casey It has to be holstered in a particular place? Otherwise the engineer might want to keep that to himself – Danny Beckett Apr 9 '14 at 21:26
• You should clarify whether you are asking about FFDO or "not commercial aviation" as FFDO only exist at airlines. – casey Apr 9 '14 at 21:27
• @casey Ah I see! Let it be commercial then. I'll edit momentarily. – Danny Beckett Apr 9 '14 at 21:28
• It has to be briefed as different door procedures will be in effect. Ill figure out what I can or cant say and post an A later. – casey Apr 9 '14 at 21:29