When I traveled internationally out of DTW on NW a few years ago, everyone's bags had to be X-rayed before checking in my luggages. Specifically, DTW-NRT/KIX.

These days, no one has to send their luggages through the X-ray before checking them in. A NW agent told me that the computer decides whether or not I have to bring luggages to this gigantic $1 million human-operated explosives detector on the other side of the check-in area (which then leads to the conveyor belt).

Does this mean that other luggages are not inspected? (scary thought) Or that the explosives detector is just an optional supplement to some x-ray machine somewhere inside the luggage transport system? (Is that x-ray system human operated?)

What about connecting domestic to international flights?

- Pat