The air raid means the danger of a possible aerial bombardment.
Air raid sirens signify an emergency situation, such as an imminent attack or a natural disaster, where people need to take immediate shelter and follow safety procedures. They are used to alert the public and ensure a quick response to potential danger.
The danger of being subjected to aerial bombardment .
The air raid sirens sounded when approaching bombers were picked up on radar or were seen crossing the coast and heading for large cities. The sirens warned people to head for air raid shelters or to take cover in their own homes. When the danger was over, the sirens sounded again with a different tone to signify 'all clear'.
Air raid sirens
I should imagine the air raid wardens by sounding an air raid siren!
air raid sirens would signal there was going to be an air attack when this happened people would cram into air raid shelters
Sirens.
Many tornado sirens are former air raid sirens.
Answer: Air Raid sirens. --------------------------------------------- the enemy is coming to kill us run for y'all lives
Air raid sirens were mounted to telephone poles, buildings and light poles. They were powered by electricity. They did not have solar power then. There are solar powered sirens now. They did have hand cranking sirens then. There were some men who were hit by bullets while they were cranking the sirens. The Nazis wanted to get the siren silenced.
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To let people know that an air raid was coming so they could seek shelter before enemy bombers dropped bombs on them. Without the sirens, the bombs would have been falling before they would have time to get to a shelter.
When the Air Raid sirens stop and the bombs stop falling it is safe to leave.