On June 28, 2010, an aerial spray plane owned by Jonair Ltd in Canada clipped the top of a meteorological tower used to measure wind speeds and direction for a possible wind energy facility. The plane was preparing to spray a near-by field. The tower had no markings, paint or lights on it, making it difficult to see. According to Jonair president, John Brodie, notice is not required when met towers are erected so his pilots do not know to look for them. The pilot was not harmed.
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Jonair Ltd. letter - aerial spray plane damaged by met tower
This letter describes a serious incident involving an aerial spray plane that clipped the top of an unmarked 198-foot meteorological tower.