Imagine this. You’ve spent the week sight-seeing in New
York City, but the time has come to return home. Filled with memories of Times Square, Central
Park, and the Statue of Liberty, you start to make your way back to the airport. So far today though, things haven’t exactly
gone to plan. It’s been freezing cold all day and everything
is delayed because of the terrible weather. After battling through the chilling nineteen
degrees temperature, you got to the airport half an hour early, only to find out your
plane had been delayed. Typical. It seems like everyone is in the same boat,
so the airport is full of people making angry phone calls, having petty arguments with their
family or walking around looking disgruntled. When it’s finally time to board, the plane
is completely full. You end up in the middle seat. The guy on your left has a strange smell,
and there’s a baby behind you who's already starting to cry. “At least it’s only a two-hour journey…”
you think to yourself. So, you put on your earphones to block out
the noise of the crying infant and pray you’ll manage to get a little shut-eye. When the flight attendant passes, you hide
your earphones with your hair so she doesn’t make you listen to the safety briefing instead
of Britney Spears. You’ve heard it all before, and everyone
knows it’s safer to ride a plane than a car, right? You look out the window, partly to distract
yourself from that guy on your left and partly to catch your last glimpse of the Big Apple. With the soothing sound of Britney filling
your ears, you start to drift into a restful slumber as the plane climbs higher. You watch as the skyscrapers of New York start
to look like a model village and the Hudson River becomes a tiny ribbon. What a view! You even see a flock of geese fly past. “Weird,” you think to yourself; “come
to think of it, I’ve never seen birds from inside an airplane before.” But then, before you know it, the breath-taking
view is replaced by fire, smoke, and a load of black stuff coming out from what looks
to be the engine. There’s a loud boom as if there’s been
an explosion, and the whole plane starts to shudder and shake. What’s going on? Did something happen to the engine? It couldn’t have been the birds – right? Believe it or not, this really happened to
the unlucky passengers who boarded the US Airways Flight 1549 back in January 2009. Just ninety seconds after the flight took
off from New York’s LaGuardia Airport, the plane met with a flock of Canada geese, some
of which were sucked into the plane’s engine. When a bird hits a plane in the air, it’s
known as bird strike. This could involve birds hitting the forward-facing
edges of the vehicle, like the wings or nose cone – but the most common place the bird
hits is the engine. If this happens, the bird will fall victim
to jet engine ingestion, when the unsuspecting creature is sucked in and swallowed by the
machine. It’s not a pretty sight. As a passenger, you’re unlikely to see what’s
happening if a bird does get ingested. It happens very quickly, so even if you’re
sitting at a window seat near the engine, all you’ll see is a blur of motion. Sometimes, that’s it and nothing much will
happen. In extreme cases – like this US Airways
flight – you might see flames, smoke, and blackness from the window. This happens because of a compressor stall:
the engine continues going at first but the compressor stops being able to control the
airflow as it should, meaning the engine can’t keep itself cool. Just like when you stall your car, this leads
to a lack of engine thrust and vibrations. In the worst-case scenario, there will be
bangs, explosions, and the engine will stop working altogether. As well as potentially causing compressor
stall, big birds can disrupt the rotary motion of the fan blades inside the engine, bending
or fracturing them. It might sound far-fetched, but according
to the Huffington Post, bird strikes are the number one threat to planes worldwide. So, you’re sitting in your seat wondering
what’s happening. As you’re watching the flames and smoke
around the engine, the plane starts to shake violently, and you hear loud bangs. But you’re still here, and the plane is
still moving. Everything must be fine, right? Maybe it was just one of the engines that
went down... Then, before you know it, everything goes
quiet. Like, deadly silence: the kind you’re only
used to hearing in a library or exam hall. Nobody is screaming or shouting, they’re
all just whispering to each other and looking to the flight attendants for some kind of
instruction. And, the next thing you know, you realize
the plane is going down and not up. You look out the window again, hoping to see
some kind of runway. Instead, you realize the plane is heading
for none other than the Hudson River. Then there’s a sound you never thought you’d
hear. The sound of the captain rings out: “Brace
for impact!” Most planes have two to four engines – if
one goes out of action, the pilot will return to the airport as a precautionary, but the
plane can still function. In fact, most aircraft can cross half an ocean
with only one engine. Not bad, right? Unfortunately, it wasn’t just one engine
that went out in the case of Flight 1549 – birds took out all the engines. See, there are two important factors here:
the size of the birds and the number of them. Engines are actually designed to keep going
when they ingest birds, so swallowing a large number of small birds or a small number of
larger birds wouldn’t be much of an issue. Only around 5% of bird strikes actually cause
damage to an airplane. But the US Airways plane ingested numerous
Canadian geese – those are some pretty big birds. Another detail to remember is that the plane
went down just ninety seconds after leaving the ground. That’s because birds fly relatively low
in the sky compared to planes, so a collision is only likely when the plane is close to
the ground, like during take-off and landing. Around three-quarters of bird strikes occur
below 150 meters. Oh, and bird strikes almost always happen
during the day since that’s when birds are flying. Basically, it takes a very special set of
circumstances to line up for birds to not only be ingested by a plane but also stop
every single engine from working. Heeding the warning to brace for impact, you
clutch the chair in front of you for dear life and duck your head down, wishing you’d
paid more attention to the security announcements. Then the airplane bounces and crashes into
the water below. The impact of hitting the water tears up the
plane, and there’s a huge shudder. Everything goes dark, and you start to feel
water flowing against your feet and legs. Freezing cold water. Terrified you won’t make it out before the
whole plane fills up with water, you jump up and try to head out through the back exit,
but an attendant is shouting at everyone to go forward instead. As you make your way up the aisles, the youngest
and fittest passengers are jumping and clambering over seats to get there as quickly as possible. Within seconds, the water is up to your waist,
and by the time you reach the door, you can see the people at the back of the plane have
water up to their shoulders. As you reach the door, you see the entire
cohort of passengers sitting on the wings. You join them at first, before jumping into
a life raft. There’s a couple of inches of water at the
bottom, so it’s freezing to be sat there, but at least you made it out. People are holding each other and crying;
some look like they can barely hold on for longer. But just four or five minutes later, you see
safety boats heading your way. You can scarcely believe it: you made it out
alive. It’s easy to see why Flight 1549 came to
be known as the ‘Hudson miracle’. Despite all the engines failing, every single
passenger survived. It was all thanks to the plane’s pilot,
Chesley Sullenberger, also known as ‘Sully’. Realizing what had happened, Sully was left
with three options. He could turn back to the LaGuardia airport,
try to land in the next airport in New Jersey, or do an emergency landing in the river. The typical procedure for bird strike is to
turn around, but Sully understood he was faced with a far more serious situation. Instead, he opted for option three and banked
the plane to the left over the George Washington Bridge, heading to the river. The rest is history. You might be wondering how he managed to steer
the plane once the engines had already stopped working. Well, as long as the wings remain intact,
the plane can be flown like normal – during a normal landing, the pilot pulls the engines
to idle anyway. The challenge was landing in the river as
if it was a runway, at exactly the right angle. Once the plane landed, it was buoyant enough
to not sink immediately thanks to being filled with jet fuel, which is lighter than water. The role of communication in achieving this
incredible feat shouldn’t be neglected, either. There are three key mandates in an aviator’s
handbook: aviate, navigate, and communicate. Sully and his co-pilot met their duty to communicate
by letting air traffic controllers know what was happening; this was vital for ensuring
first responders were able to arrive at the scene so quickly. Communication between the pilots, flight crew
and passengers was also essential for keeping everyone calm. If the flight attendants hadn’t made sure
everyone followed safety procedures correctly and kept the back door of the plane closed,
water might have come flooding in, and the whole case would be a different story. So, should we be worried about bird strike? Yes and no. The outcome of bird engine ingestion is highly
dependent on the circumstances of the flight. In 2007, a flight from Manchester to Lanzarote
suffered engine failure when a bird was ingested and caught fire, but it returned safely. On the other hand, an Ethiopian Airlines flight
in 1988 sucked in numerous pigeons in take-off and ended up crashing and killing 35 passengers. The greatest loss of life happened in 1960
on a flight from Boston, when a flock of starlings damaged all four engines and the aircraft
crashed, killing 62 passengers. These are somewhat extreme cases, but the
phenomenon is more common than you might think. According to Transport Canada, the bird strikes
cost more than $500 million a year in North America alone, although not all of these cases
involve engine ingestion. But just because they’re frequent, doesn’t
make them dangerous. According to the Federal Aviation Administration,
there have only been 25 human fatalities caused by wildlife strikes with US aircraft. The birds, on the other hand, didn’t fare
so well. Is there anything we can do to prevent bird
strike? Not completely, but we can certainly reduce
the chances. An important aspect of this is testing whether
planes are airworthy and able to withstand unexpected collisions – certification criteria
require that large engines should be able to endure the impact of a bird over 3.5kg
without serious damage. Bizarrely, this is often tested by firing
fake birds at airplane engines. It might sound brutal, but it’s an important
part of air safety. It’s even better to avoid these kinds of
collisions altogether. Some airports now have radar-based equipment
on the ground to detect birds, and they may even broadcast the sound of predatory birds
or produce loud bangs and flashes of light to keep them away. Mechanical falcons, trained falcons, and drones
have all been used too. Kind of like high-tech scarecrows. Unfortunately, birds always seem to adapt
to a new environment and stop being scared by all the deterrents put in place. And airports are like a bird’s paradise. Free food and a large, empty area with a green
space nearby? If you’re a Canadian goose, it doesn’t
get much better than that. The only way to stop birds being ingested
by engines completely would be to get rid of them altogether, but animal rights activists
might have something to say about that. In fact, in the aftermath of the Hudson miracle,
airports in New York started culling geese. Even two snowy owls were shot out of fear
they’d fly into an aircraft. Naturally, this caused some controversy and
is no longer considered best practice. Whatever we do, there’s no way of getting
away from freak accidents completely. As long as there are flying creatures roaming
the skies, they might have undesirable collisions with our flying machines. So, you don’t need to cancel your next flight
due to fear of bird ingestion, but you might want to pay attention to the safety announcement
just in case. By now you’re probably more than a little
cautious about stepping on a plane. Well, go ahead and cancel that trip to visit
family and just stay home with this great video, or maybe you prefer this other awesome
video instead? Either way, Infographics is definitely safer
than flying, so click now!
