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Okay, I say the word “Airplane” and what do you imagine? I know, a very funny movie
with really bad jokes, yeah, but let’s try harder. Okay. “Big, white, a rounded nose,
relatively small tires, two oddly angled wings with their tips curling up, normally late
taking off. Oh, and you always get on board through the left side!” Yep, spot on! But
WHY is all that so? Well let me tell ya.
- Commercial aircraft usually have their wings angled backward - that's why they're also
called swept wings. This shape helps planes be as fast as they are. The air moves over
a wing at a higher speed than under it. This creates shockwaves that would otherwise slow
the plane down. But these unique swept wings miraculously (kidding - it's just physics)
reduce the airflow speed above the wing. There are no more shockwaves, and the plane can
reach incredible speeds.
- Besides being angled toward the rear, many plane wings also have curved tips. Those are
called winglets. When a plane is flying, there’s a pressure difference between the wing's lower
and upper surface. This difference is big enough to produce wingtip vortices (they're
something like mini-tornadoes, which sounds pretty dangerous to me). Wingtip vortices
lead to slower speeds, more fuel consumption, higher CO2 emission, and safety issues. If
another plane is following one that's creating such vortices, it can lose stability and end
up in an emergency situation! Luckily, engineers invented winglets to separate the two regions
with different pressure, preventing those vortices from appearing.
- Ok, but why is the entire wing tilted upward instead of being perfectly parallel with the
ground? This upward angle is crucial for the airplane's stability. That stability is at
risk when a jet comes across some obstacle, like a bump from turbulence, that can make
it roll to either side. When that happens, the more upward wing gets less lift and naturally
goes down. The wing that rolled downward becomes more parallel to the ground and generates
more lift – making it go up. And voila! The plane levels out on its own, all thanks
to the wings' upward tilt.
- Let’s delve deeper into that oh-so-important lift – after all, it’s one of the forces
that help a plane stay in the air and move forward. The angle the oncoming air meets
the wing at is known as the angle of attack. The lift greatly depends on this angle. Take
a wing and start tilting it upward (like when a plane is taking off) - and you'll see that
the lift is getting better! But only until a certain point. If you tilt the wing too
much, the lift will get weaker or disappear altogether! Then the plane will stall in the
air and eventually fall. If the wings are tilted down, the lift decreases. You can notice
it when a plane is pitching down before landing. Long story short: aircraft wings are an engineering
marvel!
- Another thing you may spot if you're watching an airplane about to touch the ground is that
its landing gear is a bit tilted. On some planes, the rear set of the wheels touches
the ground first – like stepping with your heel. The tilt serves several purposes: to
soften the landing and absorb the touchdown shock, to level the plane and prevent it from
pitching forward, and to let the gear fit properly in the gear well.
- And since I've started talking about those wheels, you ever notice how small they are
for such a massive machine? Well, if you made airplane wheels bigger, it would add extra
load, and aircraft would waste more fuel carrying them. And the more fuel a plane consumes,
the more money an airline loses. That's why manufacturers have a tough task: they need
to make airplane wheels and tires as small, sturdy, and safe as possible, and they’ve
accomplished that!
- Airplane tires are also famous for being super inflated: the pressure inside is 6 times
greater than what’s in your car's tires and 4 times bigger than a person can withstand!
Surprisingly, thanks to this pressure (as well as the material they're made of), airplane
tires don't burst under the immense weight of a landing aircraft.
- If you're flying at night, you may see flashing lights on your airplane's wings. The light
on the left wingtip is red, and the one on the right is green. I know you can’t see
both lights from where you’re stuck back in the middle of the economy section, so trust
me on this one. That lighting scheme helps pilots figure out the direction of oncoming
planes in the dark and avoid a collision. The green and red lights on commercial aircraft
must be on from sunset to sunrise.
- Most airliners have nicely rounded noses, but there are jets with pointy ones – so
what decides it? Your aircraft's nose shape simply means that you aren't going to travel
faster than the speed of sound. During the flight, a plane's blunt nose pushes the air
in front of the jet, allowing it to roll over the airplane's body more freely and without
any serious resistance. The faster a plane is, the sharper its nose will be since they
need to cut through the air without meeting too much resistance. That's why almost all
supersonic aircraft (ones that travel faster than the speed of sound) have pointy noses.
Just like the pointy-nosed witches on broomsticks. Yes, they can go supersonic too. Didn’t
know that, did you? Then why not build commercial airplanes with
pointed noses – won't it make t hem faster? Nope! If a plane's speed is subsonic (lower
than the speed of sound), the blunt nose causes less drag - that's one of the forces that
keeps aircraft in the air but, at the same time, slows them down. Plus, pointed noses
are longer than blunt ones, so they may prevent pilots from seeing the runway clearly.
- Commercial airplanes have doors on both sides, but in most cases, you board on the
left. For one thing, it's a tradition. Earlier, airports were organized in such a way that
a plane had to taxi up to the terminal building and discharge passengers there. Pilots sat
on the left side and needed to see where they were going to put the plane's door right in
front of the terminal entrance. If they misjudged the distance, they could hit the wing against
the building. These days, left-side boarding is more of a safety concern. The right side
is used for fueling the plane and loading and unloading baggage and cargo. If passengers
were also entering aircraft from the right side, it would mess up the whole process and
probably lead to accidents. Boarding from the left side may also have something to do
with ship design. A ship's left side is a port side where people get on and off. Airplane
and jetway manufacturers might’ve just followed this maritime practice.
- Modern commercial planes have at least 6 entrances (or exits): 2 in the front of the
passenger cabin, 2 in the back, and 2 emergency exits over the wings. C’mon, you remember
that talk they give up right before takeoff? Then why don't airlines save time by letting
people in through all the entrances at once? Ok, maybe not the wing ones, but what about
the other 4? Well, you can't use the right side because of the whole baggage and fueling
thing I just mentioned. So, now we’re down to a front and rear door on the left. Some
airlines do use both for boarding and deplaning. But those are mostly low-cost carriers that
bring passengers to planes by buses and use mobile stairways. But if people board an aircraft
through a jetway, using both doors won't work. Jetways only reach the front left entrance.
To reach the rear ones, they’d have to go around the wing. In other words, jetways would
have to be longer, which equals not only more money spent but also more terminal space taken,
which is already tight. And finally, the rear and opposite-side doors are sometimes used
to load food and drinks and take out the trash. If passengers were boarding through them,
it wouldn't buy any additional time – it’d actually slow everything down.
- But returning to buses and mobile stairs: why them, why not good ol’ jet bridges that
can protect you from the elements every single time? Some airports are just too busy and
don't have enough gates. It's either using buses and mobile stairs or waiting for hours
for an available gate. Plus, if you're flying with a low-cost airline, it’ll try to save
as much money as possible (after all, it's low-cost for a reason!). Since jetways and
parking right near the gate cost a lot, budget carriers prefer much more distant parking
places, mobile bridges, and buses.
That’s it. Gotta fly!
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