The terms D-day and H-hour are used for the day and hour on which a combat attack or operation is to be initiated. ... The letters are derived from the words for which they stand, "D" for the day of the invasion and "H" for the hour operations actually begin.

What is H-hour and l hour?

H-hour. The specific hour on D-day at which a particular operation commences. ... L-hour. The specific hour on C-day at which a deployment operation commences or is to commence.

What was h-hour?

H-Hour (redundant acronym of hour) was the name given to the airborne assault during the Normandy landings of World War II. ... This took place about three hours before the main beach landings on the Normandy coast. The airborne invasion consisted of over 20,000 men and around 1,200 planes and gliders.