These balloons, known as aerostats, are located at restricted airspaces that are shown on all aeronautical charts and are well known to pilots.
Some time ago the FAA indicated that our planned demonstration should be in an already restricted airspace, and placed us in contact with military liaison officers. These officers suggested potential restricted airspace demonstration sites which Sky WindPower has been investigating, and at which interest in participating has been expressed..
Our calculations show that by reserving less than one four hundreth of U.S. air space, located at relatively remote locations not on airway routes, all its electrical energy needs could be met. Less than one four hundredth of U.S. airspace is a small fraction of the amount of airspace which civil aviation must currently avoid.
Non pilots often have the idea that pilots may fly anywhere they want, except over the White House and a few other key locations. And while understandably pilots do not like to see more restrictions on where or at what altitude they may fly, the fact of the matter is that there is already so much authorized airspace use for various specific purposes that the FAA maintains a website updated daily for use by pilots showing airspace locations and altitudes which they must avoid or seek permission to enter. This is in the form of an excellent map of the continental United States which may be further navigated, and a table of current information pertaining to the specific sites. For those interested, the site is:
Presumably the country's energy needs will also receive consideration in this airspace use as high altitude wind energy capture becomes accepted as important in addressing our energy independence and global warming problems.
Safety on the ground is a primary design consideration. The reliability of four or more rotor design, coupled with computerized advanced detection of potential problems is key.
However, the thought of a whirlybird overhead crashing is frightening, and, inevitably, crashes will occur, just as airplane crashes do occur. But statistically, FEGs, long range, should be just as reliable as commercial airliners, whose safety records are incredibly good. And FEGs don't take off or land at airports teeming with people in and around them.
Unlike nuclear fission power plants, another non-global warming energy source, FEG arrays are not a tempting terrorism target - targeting flying windmills could cause monetary damage from suicide pilots or guided missiles but do not pose radiation worries. No Chernobyl type worries exist whether from accident or deliberate action.
If an aircraft does fly into a tether, in spite of entering the airspace illegally, tethers could be severed, and passengers killed. However, it is expected that the rotorcraft could usually be brought down safely anyway.
In April of 2007 the first case of a plane flying into one of the aerostat tethers occurred off Key West, Florida, for the first time after over thirty years of no accidents. Three people were killed in this light plane flown by a private pilot at night illegally into this restricted airspace, and without utilizing available warning electronics.
There is risk in any undertaking, and civilization must balance the risks against the benefits after implementing reasonable precautions, such as the electronic avionics warning system, initiated by the FAA, and paid for by our tax dollars.
