An Icelandic airport worker recently captured
the dramatic sight of a plane being hit by
lightning. How do they survive such
spectacular strikes?
Halldor Gudmundsson had just seen a huge
lightning strike near his office, northwest of
Keflavik International Airport in Iceland.
He
flipped open the camera app on his phone and
started recording, hoping to catch another fork
of electricity rip through the sky. But suddenly
a plane, taking off from the airport, flew into
view – and was immediately struck by a flash
of lightning.
It was an extraordinary sight, but the aircraft
soared on regardless, through heavy rain. “It
was very fun to see, but also a bit scary,”
says Gudmundsson, whose footage provided
this extraordinary photograph.
The Wow Air flight from Iceland’s capital
Reykjavik to Paris on 3 October arrived safely
and the airline confirmed to the BBC that the
plane was not damaged in any way. As a Wow
Air spokeswoman pointed out, it’s not
uncommon for aircraft to be struck by
lightning. How, then, do they survive a sudden
shock amounting to approximately 1 billion
joules of energy – equivalent to a quarter-of-
a-tonne of TNT.
The “skin” around the cabin and interior
compartments of an airplane is designed to
conduct electricity but keep it away from the
crew, passengers and electronics inside,
explains Chris Hammond, a retired pilot and
member of the British Airline Pilots
Association (Balpa).
“There’s a metal mesh that goes into the skin
of the airplane,” he says, “a sort of gauze that
goes the whole way through – and that’s how
the electricity is conducted.”
Like a flying Faraday Cage, everything on
board is protected
In addition, the electronics and connections to
the fuel tank, for example, are heavily shielded
to protect them from external electrical bursts.
All of this is rigorously tested before an
aircraft goes into service – a process that
involves simulating lightning strikes to the
skin and internal components.
Gudmundsson’s photograph, notes Hammond,
is an illustration of everything working exactly
as it should.
The bolt appears to enter the
plane at the nose and then exit via the tail
and part of the wing. Like a flying Faraday
Cage, everything on board is protected.
A lightning strike is still likely to be noticed by
people on board, though.
Passengers on two
flights that were hit over west London in April
reported hearing loud bangs, for example.
Years ago, aircraft were not as well insulated
from strikes.
Hammond remembers piloting an
early airliner while waiting to land in San
Francisco. After a particularly bad flash, he
recalls, “all the screens went blank”.
Thankfully, the aircraft was equipped with
analogue instruments at the time. While the
computers gradually came back online, the
plane was able to land safely.
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