LIGHTNING BOLTS
ARE SHOOTING
THROUGH EVERY POWER
LINE–CONTINUOUSLY.
AN ERROR WOULD
IGNITE AN 18,000°F
SURGE OF HELLFIRE.long as he keeps his distance from
the adjacent power lines. Neither the
mast nor a leaf on a nearby tree can
touch him or the helicopter. If contact
were to happen, the result would be a
fatal shock because an electric circuit
would be completed between the line
and the ground. The biggest obstacle
to working on the cables is the wind:At a height of 160 feet, wind usually
blows almost twice as hard as it does
back on the ground. For this reason,
the team will only work when the wind
speed is less than 30 miles per hour,
otherwise it would be too hard to keep
control of the helicopter. Because in
this job you only make one mistake—
the fi rst and the last.THE LIFESAVER
for the technician is his protective suit.
The current fl ows through it, thus it fl ows
along rather than through the body.THE FINAL CONTACT
the technician has after returning to the
helicopter is always with the compensating
cable. It is the last thing to be detached.During construction of a new line, the
workers must prepare the cable for
handling enormous amounts of energy.
Almost half the amount of electricity
contained in a lightning bolt fl ows
through the cables, which are made
of steel and aluminium and are just a
few centimeters thick—not just for
milliseconds, but continuously. If a
person were to bridge the voltage
difference between the power line
(500,000 volts) and the mast (0 volts),
his body would instantly be grilled at
up to 18,000°F. Unlike ground cables,
the overhead power lines are only
insulated by the air.
PHOTOS: Christian Schmidt/Gallery Stock; DDP; Getty Images; YouTube (5).
ideasanddiscoveries.com 59 Mar 2017INSULATORS
To avoid current
flowing out to the
masts, the cables
are hung from
insulators that
are made from
glass, porcelain,
or plastic. Their
ribbed design
increases the
impediment to
the current.AIR-TRAVEL OBSTACLE
Beginningataheightof
330 feet, electrical masts
are generally considered
an obstacle to air travel.
That’swhytheybearred
and white signal colors.BLACKOUT
Only switched off in an emergency:
If the current has to flow through
alternative routes, total failure
threatens the ailing power network
in the U.S. That’s why electrical
techniciansmustclimbonpower
linesthatareactive.