In today's modern U.S. airspace, pilots are perpetually reminded of the dynamic nature of TFRs. If NOTAMS are not checked and flight-paths left unmonitored, unpleasant surprises may become airborne in a "TFR Temporary Fright Restriction".
An altimeter is an instrument which determines an aircraft's elevation above sea level. Many instrument panels have back-up altimeters. If your flying machine lacks a secondary device, wearing "Altimeter" will be a great alternative substitute.
