preparedness, readiness, preparation - the state of having been made ready or prepared for use or action (especially military action); "putting them in readiness"; "their preparation was more than adequate"

air alert - the condition in which combat aircraft are airborne and ready for an operation; "aircraft in the Mideast are on air alert"

red alert - the highest level of alert when an attack by the enemy seems immanent (or more generally a state of alert resulting from immanent danger)

strip alert - a state of readiness for domestic defense aircraft; "the Air Force will keep fighters on strip alert at bases around the country"