ever since Orville and Wilbur Wright
flew at Kitty Hawk airplanes have had
wings controls and some kind of motor
but planes have evolved over the last
hundred years the commercial airliner
you fly in now has features that Orville
and Wilbur wouldn't have dreamed of in
this video I'll show you 10 things you
might not know about modern aircraft
from the mysterious to the curious
bagsy number 10 the mysterious triangle
symbol over your seat when you board a
modern jet aircraft you're probably
looking for your seat number and for the
nearest emergency exit if you look more
closely you might notice a small
triangle over your window that's not a
secret society symbol it's a reference
mark for the flight crew there is a
triangle at the front or leading edge
and back or trailing edge of each wing
the center of the wing is ideally the
center of gravity of the plane for
balancing the controls imagine balancing
a long tray with a glass on it on your
finger it's easiest if the glass or
downward force balances the upward force
from your finger if you move the glass
to away from your finger the tray will
want to tip so if the flights not full a
flight crew member might ask you to move
between these rows to distribute the
load for easier control of the plane
which translates to less drag and better
fuel efficiency as well it's also a
quick way to spot which windows shade to
pull up if the crew needs to inspect the
wing during flight number nine the
flange sticking out of the wing while
you're waiting to leave the gate you're
probably staring out the window at the
wings that are going to carry you off
this earth on some aircraft like the
a320 you might notice a metal stub
sticking out in the middle of the wing
like a sore thumb no that's not for
lifting the plane this is part of the
evacuation system if the plane is forced
to land somewhere that you can't use the
stairs or the terminal boarding bridge
the crew will deploy inflatable chutes
from the emergency exits but if you use
one of the over-wing exits you'll have
to step out onto a slippery metal
surface those stubs or wing flanges are
anchors for tying guide ropes that
little stub will guide you safely off
the wing without stubbing your toe
number eight the hum when you board the
plane
have you ever noticed that there's an
omnipresent drone when you're waiting
for the last passenger to board the
plane the engines aren't powered up yet
but something is running that's the
sound of the auxiliary power unit or APU
the APU is what provides electricity to
the plane temporarily between the time
the plane unplug from the terminal until
it is ready for takeoff the APU is
usually a small turbine that powers a
generator for electricity and a
compressor for air pressure the APU
powers everything from the cabin lights
and fans up to starting the main engine
it even provides a fire protection
system this system uses less fuel than
running the main engine since it's only
designed for cabin operations not for
driving the plane the flight crew will
start the APU before letting any
passengers board so you can sit in
comfort and safety while they prepare
the plane for departure if you pay
attention you can see the lights dim
temporarily and here when they switch
from terminal power to APU now you know
why your movie was interrupted for a few
moments number 7 tomato juice do you
find yourself ordering a tomato juice
when you're on a plane ever wonder why
you suddenly crave a salty vegetable
drink that you wouldn't give a second
glance to on the ground it's the same
reason you think airline food is bland
everything on board a plane is
conspiring against enjoying the food
scientists have studied this and it's
not just your imagination
first the noise of the engines dulls
your ability to taste sweet things food
scientists at Cornell found out that
sound levels at 85 dB the same level as
airplane engines reduce the effect of
sweetness on taste buds and that fan
over your head is blowing air that is
much drier than you're probably used to
at home lower humidity means you can't
smell as well on top of that as the
plane climbs the cruising altitude the
pressure inside drops you feel that when
you pop your ears that pressure drop
affects your sense of taste too so next
time you wonder whether to order the
fish or the chicken just order a Bloody
Mary with extra Tabasco and savour that
serving of tasty tomato number six
opening window shades for landings and
takeoffs I bet you thought the window
shades were installed on planes so you
can sleep during long flights but then
the flight attendant asks you to open
the shade before takeoff and
when they're going to land why don't
they just look out their own window yes
the shades are there to give passengers
control over their own environment but
safety takes priority over comfort the
most critical part of any flight is when
it's near the ground those windows
aren't just there for sightseeing if
something happens to the power on board
the only light besides the illuminated
arrows to the exits will come from the
windows and if someone have to open an
emergency exit they need to check
outside for debris fire water or other
hazards first the Federal Aviation
Administration requires that planes can
be evacuated within 90 seconds so
remember that window shades work both
ways and make sure yours is up whenever
taking off or landing it will give you a
great view before you're too high to see
the sights and it might just help you
see your way to the door in an emergency
number five winglets airplanes are
always a tug of war between the thrust
of the engines and aerodynamic drag one
big source of drag is something you
might not see unless the temperature and
humidity are just right have you ever
noticed little swirls of mist trailing
from the wingtips
those are wingtip vortices these little
whirl winds tug at the tips of the wings
as the smooth layer of air flowing over
the wing that gives it lift breaks away
every tug is like a dog pulling at your
pant legs as you're trying to walk
slowing you down in wasting energy on a
plane that translates into fuel those
little winglets ticking up at the end of
the wing stop the vortex from forming
which reduces drag and saves fuel which
saves you money number 4 side stick back
in the day of the first planes pilots
were known as stick and rudder men
steering the plane by the power of their
arms and legs pushing on control cables
those planes were much smaller and flew
much slower than your modern jet though
commercial aircraft are designed with
electronic systems that take fingertip
commands from the flight deck to massive
ailerons that would dwarf that first
balsa-wood plane at Kitty Hawk these
fly-by-wire systems are controlled using
a side stick that looks like the
joystick from a computer game giving
today's pilots an ergonomic replacement
for battling that old steering column
the side sticks are actually linked
together so the pilot and co-pilot can
both roll and pitch the plane now don't
think they're battling each other like a
video game
is a button to choose which pilot is in
control it's got a few more buttons
including a push-to-talk button for
talking on the radio and another for
switching the autopilot on or off it has
built-in sensors that allow the pilot or
co-pilot to take immediate control by
applying sufficient pressure don't worry
it's also connected to warning lights
and alarms to notify the pilot when the
autopilot is disengaged and which pilot
has control number three bleed air
system while the Wright brothers flyer
barely flew above the dunes at Kitty
Hawk today jet liners fly higher than
the tallest mountains climbers talk
about the Death Zone about 3000 meters
so when the plane reaches cruising
altitude it has to keep enough pressure
inside for people to stay alive without
pressurized air you'd soon be sounding a
little drunk before falling asleep as
your brain is deprived of oxygen now to
find these rarefied Heights part of the
design of any high-flying airplane is
how to keep the air flowing one source
of the pressurized air on jet airliners
is called the bleed air system bleed air
comes from a side port on one of the jet
turbines it is only a small percentage
of the air blasting through the jet and
is controlled to keep a comfortable
atmosphere in the cabin the air is also
heated as it passes through the turbine
otherwise the cabin would drop to the
outside air temperature which is around
minus 60 degrees Celsius at 10,000
meters cruising altitude so that engine
hanging off the wing isn't just
propelling you forward it's also
supplying you with enough air pressure
so you and the flight crew won't pass
out number two the eye level indicator
on cockpit window pilots come in all
sizes and just like your car planes have
adjustable seats for them and just like
you might use the hood ornament at your
reference when you adjust your car seat
and mirrors pilots have a reference for
pilots to make sure they're in the right
spot to see their controls and outside
it's called the eye level indicator and
it's just a small knob on the cockpit
window while the pilot operates the seat
adjustment levers he or she keeps their
eye on the little red ball on the
indicator until it lined up with a white
ball so that 50 percent of the review
covers outside the window and 50 percent
on their instruments inside not only
that this ensures the pilots are
positioned so all the controls and
switches are in the same place every
they sit down this low-tech solution is
all that's needed to make sure your
pilot can gauge approaching objects and
reach the appropriate controls to react
without taking their eyes off the ball
number one the hole in your window
since cabin pressure is so important you
might think a hole in your window is a
good thing but if you look closely
you'll see every window has one about
the size of a strand of spaghetti that
hole lets the pressure between the cabin
and the air between the pane equalize
like your house windows the layers
insulate from the extreme cold of high
altitude flight but unlike your house
airplane windows have to deal with large
changes in pressure as the air climbs
and descends there are actually three
layers in an airplane window the inner
pane is plastic and just protect the
glass from scratches the middle pane has
the small hole that lets the air between
the panes expand and contract but still
provides insulation if you didn't have
the middle pane you'd be looking through
a layer of ice as the moisture in the
cabin air condenses on the cold outside
glass that's just a few things you might
not have known about airplanes do you
know of any other interesting features
of planes let me know in the comments
section down below also please be sure
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