• U.S.

The Hemisphere: Ready for Alerts

2 minute read

The shortest distance from Russia to America’s industrial heart lies across the North Pole and down through the expanse of Canada. Last week, to help guard this vital approach, four more zones of a coast-to-coast air-defense system went into operation along the Canadian-U.S. border.

On the U.S. side, Air Defense Identification Zones (ADIZes) are up to 535 miles deep; on the Canadian side (CADIZes) they are narrower and there is a gap in the prairie belt where the system is not yet in operation. Areas on both sides of the border are rigidly policed. Airmen planning to fly in them must file a flight plan; failure to do so is punishable by a $10,000 fine and a year’s imprisonment. Radar stations plot the flight to make sure an expected plane is no more than five minutes off schedule or 20 miles off course. If an aircraft is not identified within three minutes, R.C.A.F. (or U.S.A.F.) fighters streak skyward.

If the plane appears hostile, a yellow alert (attack likely) is flashed to civil-defense officials in the potential target area. A red alert (attack) is the signal for sirens to wail and people to seek shelter. Meanwhile, in defense jargon, fighters will “take appropriate action,” i.e., try to shoot down the intruder.

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