In April, a single-engine Piper aircraft flew into a wind turbine and crashed. Four people were killed. The incident seems to have gone virtually unmentioned in the media.
The accident occurred in the US, in South Dakota. There was one person, the pilot, in the aircraft and he worked for local crop-spraying company AirKraft Spraying. Also killed were three cattle farming experts, who were returning from a yearly cattle sale in the town of Hereford.
The cattlemen were experts in cattle genetics and farmed in the area. Apparently, at the time of the incident, the weather was not great. It was somewhat foggy, and the crash occurred about 15 km south of the city of Highmore. But the weather was not so bad that an experienced crop-spraying pilot should not be flying. The authorities are investigating.
The wreckage was scattered around at the South Dakota Wind Energy Center, which has 27 wind turbines. The turbines are about 150 m tall at the tips of their blades. Bear in mind as well that, when the blades are turning, they would be difficult to see. In fact, even if a blade was not turning, it would be difficult to see. The blades are long and narrow.
One commentator said that they would have to investigate why the pilot “was flying so low”. Well, I do not consider that very low. Ponder it. A height of 150 m is the size of a substantial multistorey building. The pilot was an experienced crop sprayer used to flying much lower than that. Perhaps it had been easier to navigate by flying under some fog where he could see the ground, which he probably knew well.
The local weather service said that there was low cloud at the time, so it strikes me that it would have been likely that an experienced pilot, in a small plane, would have gone low.
There were 27 turbines, which cover a substantial area of ground, because turbines have to be widely spaced so that the air turbulence from one does not affect another. There was no doubt also about some air turbulence above the height of 150 m, maybe as much as another 50 m.
To put it bluntly, such a wind farm is a major potential hazard for aircraft, particularly in a crop-spraying area.
One wonders just how much such factors are taken into account when deciding where to site wind farms. In South Africa, wind farms are mainly in the Cape, in areas which are associated with rolling hills and wine farms in a number of instances. These types of farms use crop-spraying aircraft.
How much of an air hazard has now been introduced over significant areas?
I also know of cases where weather radar at airports has signalled the approach of a low-flying aircraft, only to find out that the radar had detected a wind turbine. South African weather radar is extremely sensitive, and can detect moving air at a distance of 100 km. It does this by picking up the movement of dust particles in the air. This particular function is very important in watching air in the vicinity of airports, or in other critical places, to be able to warn aircraft of dangerous crosswinds.
When I think just how stringent the environmental-impact assessments (EIAs) are for the construction of a nuclear power plant, then it is quite a joke that the EIAs required for wind farms seem to be totally simplistic in comparison.
Turbines kill birds and bats by the thousand, but this does not seem to worry folks. But let just one seagull be threatened by a nuclear power plant . . . and . . . well you can imagine.