We are being told that 1200’ is an adequate setback for the mega-turbines slated for this part of New York State and that 600’ from property lines is reasonable. Those in favor of these figures are either total Neanderthals or just like playing fast and loose with facts and other people's lives.
Composites are now the main structural material in many boat hulls, power transmission poles, buildings, vehicles, aircraft structures, other large monolithic structures and, of course, wind turbine blades.
In aviation, so I am told, there are mandatory inspection documents which are issued whenever a problem is discovered or thought to exist. These are called “airworthiness directives,” or “AD’s.” Many have been issued recently for composite structures on jet aircraft, the same kind of “plastic” components of which turbine blades are made, but under far more stringent regulations and inspections than the wind energy industry enjoys. The introduction of composite components was the most radical change in commercial aviation since the advent of the jet engine of the early 50’s.
On Nov. 12, 2001, a catastrophic disintegration of a composite rudder and vertical fin occurred on an Airbus 300 near J. F. K. airport in New York. The ensuing crash killed 265 people in the second-worst air tragedy in history. In March of 2005 the rudder of another Airbus aircraft, this time an A-310, literally exploded and most of the rudder wound up in the Florida Straits.
In both of these and a list of other incidents, carefully manufactured and highly inspected composite parts were subjected to severe and massive delamination areas that could not be seen nor anticipated. In “composites” (a generic term meaning the product of joining different material surfaces under pressure and heat to form a lightweight yet strong structural entity), once the delamination process begins, rapid propagation and eventual failure of the structure can occur. Other aircraft have experienced partial or entire flight surfaces tearing off or becoming useless due to a hidden flaw in the manufacturing process and/or unusually rough handling of the structures, long-time fatigue or other factors. In no other industry are components as rigidly constructed, inspected and maintained as in commercial aircraft.
Yet, wind turbine blades – of similar construction and materials – never undergo the costly, painstaking treatment as do aircraft parts. Current materials, while generally strong and lightweight, can suffer these kinds of failure. Whether made from older technology glass fiber reinforced plastic (GFRP), aramid fiber reinforced plastic (AFRP), or the newer carbon fiber reinforced plastic (CFRP), the sandwich design of these surfaces – sometimes using a “honeycomb” design – and often a combination of technologies, can become contaminated. Lightening, bird strikes (Oh, yes; this all can happen, contrary to developers’ claims), moisture ingress and hydraulic fluid contamination and other factors can cause failure of the blades.
Question: how far can a turbine blade be “thrown” if the tip speed is in the neighborhood of 175 mph?
Possible Answer: Depends on the point at which the blade or portion of the blade separates from the rotor (angle with the horizontal) and how big a piece results. Chances are, it might travel “a country mile.”
Question: if an entire tower were to blow over while the rotor is turning at it’s operational speed, when the rotor strikes the ground, how far will the shattered pieces fly? (The “fall zone” is considered twice the height of the entire structure and is a minimal “safety area.” Shattered pieces could travel well outside of the fall zone, or in the case of the Cohocton towers, something in excess of 840’, perhaps a good deal farther.
Question: is it safe to assume (never “assume” anything!) that the stated 1200’ setbacks would be adequate in the event of a collapse? If there were a structure at the 600’ property line but owned by a non-participating landowner, what recourse would he have against the wind developer or lessee if the building were damaged?
Does anyone with a modicum of education really believe that living in a dwelling 1200’ feet from an industrial giant is a safe, prudent or reasonable distance? Do we really need these onerous and intrusive machines literally in our backyards? The politicians think so but, then, they won’t have ‘em anywhere close to their properties.
Sorry … I forgot. We’re just the country bumpkins who don’t have a clue about anything. Or, do we …?
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