Published: Dec 08, 2010 5:28 PM EST
Updated: Dec 08, 2010 2:28 PM EST

PAHOKEE, Fla. (AP) - Three helicopters have crashed in South Florida during missions to protect crops from the cold. All three pilots survived.

Palm Beach County sheriff's officials said the first helicopter went down shortly after midnight Wednesday near the Pahokee Airport. A second helicopter crashed before dawn when the pilot made an emergency landing after a tail rotor broke. He suffered minor injuries.

The third helicopter crashed in a field a few hours later. The pilot suffered major injuries, but they are not considered life threatening.

Roughly two dozen helicopters were flying low over crops in Glades County, helping to push air down to the ground to prevent cold and frost from settling on plants. ---

Information from: The Palm Beach Post, http://www.pbpost.com

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