The pact also restricts the height of a planned transmission line to 120 feet (36.6 metres) above ground level.

The Navy says the agreement ensures continuation of critical flight missions near Naval Weapons Systems Training Facility Boardman in Oregon.

E.ON Climate and Renewables wants to install 223 turbines in north-central Oregon.

Turbines near or within Navy airspace can interfere with training and testing, as well as radar and telecommunications.

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