Definition
An operating setting on certain avionics units, such as a GPS receiver, that suspends normal navigation functions while the aircraft or equipment is being moved on the ground or transported by other means. In this mode the unit does not compute or display navigation data, but settings and stored information are preserved.
Plain English
A setting that puts the equipment in a kind of standby state while the aircraft is being moved or hauled, so it isn't trying to do navigation work when it shouldn't be.
Context Anchor
Seen in ELT maintenance, removal, installation, and shipping instructions.
Why Pilots Care
Selecting Transportation Mode prevents the unit from logging meaningless position changes and can protect stored flight plans and settings during ground movement or shipping.
Analogy
It is like a safety lock used during shipping: helpful while the equipment is being moved, but not something you want left on when the equipment is supposed to protect you.
Intuition Check
Transportation Mode does not mean the aircraft is operating as transportation. It means the ELT is being made safe to transport and is not in its normal ready-for-emergency state.
Example Sentence 1
Before the mechanic towed the aircraft to the maintenance hangar, the pilot put the GPS into Transportation Mode.
Example Sentence 2
Switching from ground to air transportation mode reduced delivery time significantly.