Powerlines, the nemesis of balloonists, offer three dangers to flight. Powerlines are an obstacle which can sever the basket from the envelope, causing it to fall to the ground. Powerlines carry electricity which can electrocute and cause fire.
The balloon community may have suspended research into ways to protect ourselves from the hazards of powerlines because we have convinced ourselves that non-conductive suspension cables on a balloon are a safety device. Can Kevlar cables really save us from injury and death, or are they mainly a marketing gimmick?
Kevlar cables have been promoted as a safety device because they are supposedly non-conductive, however we wonder if non-conductivity is really an asset. Kevlar itself is non-conductive, however dirt and moisture, which gather on the rough, absorbent surface of the cable cover, will conduct electricity, as will dirt on an envelope.
Kevlar is touted as being "stronger than steel." In the first place, it should be said that Kevlar is stronger than steel for its weight. In the second place, so what? FAA regulations require the same strength factor whether the cables are made of Kevlar or steel. Does anyone believe their steel cables aren’t strong enough? Or are too heavy? There is no practical way to determine if steel cables are airworthy; there are no comparable tests for Kevlar. Has there been any reliable research that proves non-conductive cables are a safety factor, or are we accepting conjecture and sales propaganda as fact?
In 1928 Ward T. Van Orman, probably the greatest gas balloon pilot of all time, did much research into the properties of electricity after a lightning bolt killed his co-pilot in a balloon race. He state "a human body is a better conductor of electricity than the [balloon] rigging or the air, itself." He designed a device that surrounded the basket with conductive wires, "an adaptation of a Faraday Cage which attracts electrical bolts to itself instead of the balloon occupants." Although Van Orman was protecting himself against lightning, rather than electricity released from a powerline strike, the principle is the same: why should the human occupant of a balloon basket be the most attractive conductive objects to electricity.
According to the Balloon Federation of America’s Powerline Safety Manual, accident statistics indicate that falling due to the basket being severed from the envelope is more likely to be the cause of injury in a powerline strike than electrical shock. This indicates we need basket-to-envelope suspension that will resist severing when abraded along metal wires. Steel resists abrasion much, much better than Kevlar.
Thousands of safe flights have been made in balloons with steel cables, as well as in balloons with Kevlar cables. people have been injured or killed in balloons with steel cables, as well as in balloon with Kevlar cables. Is there a solution we haven’t found to the powerline problem? have we stopped looking because of Kevlar?
Non-conductive fuel lines in a balloon basket seem also to pose a more serious problem than they solve; they are more likely to be severed or torn loose in a collision with a powerline (or other obstacle) than fuel lines with metal reinforcement. Moreover, metal-reinforced fuel lines, along with metal suspension lines, may form part of a protective Faraday Cage inside of which people are provided some protection from electricity because they are not the best conductors in the basket.
Kevlar suspension lines, with their promise of non-conductivity, may instill a false sense of security in pilots, so they are not as diligent as they should be in avoiding powerlines. Does the promotion of non conductive balloon parts as a safety device seem to grant pilots permission to hit powerlines with impunity, or take away some of the dread of powerlines? Powerline strikes can be deadly, regardless of what materials are used.
There is no material extant that replaces constant vigilance by both the pilot and the passengers to see and avoid powerlines.