Positive lightning is a type of lightning strike that comes from apparently clear or only slightly cloudy skies; they are also known as "bolts from the blue" because of this trait. Unlike the more common negative lightning, the positive charge is carried by the top of the clouds (generally anvil clouds) rather than the ground. The leader forms in the sky travelling horizontally for several miles before veering down to meet the negatively charged streamer rising from below.
Positive lightning makes up less than 5% of all lightning strikes. Because of the much greater distance they must travel before discharging, positive lightning strikes typically carry six to ten times the charge and voltage difference of a negative bolt and last around ten times longer. During a positive lightning strike, huge quantities of ELF and VLF radio waves are generated.
As a result of their greater power, as well as lack of warning, positive lightning strikes are considerably more dangerous. At the present time, aircraft are not designed to withstand such strikes, since their existence was unknown at the time standards were set, and the dangers unappreciated until the destruction of a glider in 1999.
The standard in force at the time of the crash, Advisory Circular AC 20-53A, was replaced by Advisory Circular AC 20-53B in 2006, however, it is unclear whether adequate protection against positive lighting was incorporated.
Positive lightning is also now believed to have been responsible for the 1963 in-flight explosion and subsequent crash of Pan Am Flight 214, a Boeing 707. Due to the dangers of lightning, aircraft operating in U.S. airspace have been required to have lightning discharge wicks to reduce the damage by a lightning strike, but these measures may be insufficient for positive lightning.
Positive lightning has also been shown to trigger the occurrence of upper atmosphere lightning. It tends to occur more frequently in winter storms, as with thundersnow, and at the end of a thunderstorm.
Iv been sootn along at 2' over an open plain under a thunder head and a bolt struck the ground only a few feet outside of me disc.
Kinda craped meself.
Dont recon a fried rotor bearing would help if it decided to rout through me machine.