Refund policies can vary depending on the supplier and the specific circumstances of the booking. Generally, refunds are only possible if the Traveler has purchased Travel Insurance that covers cancellations.
For military deployments, for example, refunds might be possible if travel insurance was purchased, but typically, airfare or credit toward another flight is not refundable.
Additionally, registration fees for events or FAM trips are usually nonrefundable due to the administrative work involved and to deter cancellations.