H-HOUR.

This is coolbert:

"H-hour — 1. The specific hour on D-day at which a particular operation commences. 2. In amphibious operations, the time the first landing craft or amphibious vehicle of the waterborne wave lands or is scheduled to land on the beach, and in some cases, the commencement of countermine breaching" operations

An obligatory post! The Sixth of June, 1944. H-Hour. 

From the journal of Bernard Larsen's Journal a portion of the first paragraph as extracted.

"A FEW HOURS

AFTER H-HOUR"

"We were on ships that came in at the time we were to start our work. We were supposed to come in a few hours after H-Hour on D-day, at a certain signal by radio from shore. So on the morning of June 6, 1944 we were in the Channel with the shores of France dimly visible . . ."

See the link. Thanks to the tip from Bill!  https://tinyurl.com/4nzkdepy

Devoted readers to the blog strongly encouraged to read the entire journal, experience of one man for that one day. 

Understand full well for a time the situation at Omaha Beach in doubt. Nothing going according to plan. Troop losses excessive, goals not achieved. General Bradley had for a while had even contemplated to evacuate the landing force at Omaha. 

coolbert.