17
Aircraft 17-
Less than 100 years ago, even the fastest ship took more than
a week to cross the atlantic ocean. today most jet airliners (large
passenger planes) can make this 3,000-mile (4,800-km) journey in less
than seven hours. aircraft are the fastest way to travel because they can
soar straight over obstacles such as mountains and oceans. Powerful
jet engines enable the fastest combat aircraft to reach speeds in excess
of 1,500 mph (2,400 km/h)—more than twice as fast as sound. even
ordinary jet airliners fly at more than 530 mph (850 km/h). Modern
aircraft are packed with advanced technology to help them fly safely
and economically at great speed. sophisticated electronic
control and navigation systems
keep the airplane on course.
Computer-designed wings help
cut fuel costs. and airframes
(aircraft bodies) are made
of metal alloys and plastic
composites that are
lightweight and strong.FLight deCk
the captain and crew control the
aircraft from the flight deck. in the
past, the flight deck of an airplane was
a mass of dials and switches. new jet
airliners are packed with electronics, and
computer screens have replaced the dials.
other new features include computer-
controlled autopilot systems that enable the
plane to take off and land when bad weather
obscures the pilot’s vision.Jet airLiner
Like all jet airliners, the Boeing 747-400 flies
high above the clouds to avoid bad weather.
its airtight cabin is pressurized—supplied
with air at a suitable pressure. this protects
passengers and crew from the drop in
air pressure and lack of oxygen at
high altitudes.FLying an airPLane
every airplane has three main controls: the throttle to
control speed; rudder pedals for turning the plane’s nose
to the left or right (yawing); and a control column that
tilts the aircraft to either side (rolling), or up and down
(pitching). the pilot usually operates all three to guide
the plane through the air.The undercarriage (landing wheels)
folds up inside the airplane during
flight to reduce drag (air resistance).ConCorde
this airliner, in service
from 1976 to 2003, was supersonic,
which means that it flew faster than sound. it
cruised at more than twice the speed of sound,
crossing the atlantic ocean in less than four hours.AileronTo pitch up or down, the pilot
pushes or pulls on the control
column, raising or lowering the
elevators on the tail wing.To roll, the pilot moves the control
column to the left or right, which
raises the ailerons on one wing
and lowers them on the other.ElevatorRudderairPLanes
airplanes are powered aircraft that have
wings. the word aircraft describes all
flying machines, including helicopters,
gliders, hang gliders, and
airplanes. Most large
airliners and combat
airplanes have jet engines
enabling them to fly fast and
high. But jets are expensive and
use a lot of fuel, so many smaller
planes are driven by propeller,
just like the first airplanes.oBservation PLanes
specially designed aircraft give
a clear view of everything from
traffic jams to diseased crops.Jet airCraFt
each year billions of people make long
journeys in jet airliners and smaller
business jets. these aircraft are powered
by a type of jet engine called a turbofan.
turbofans are powerful and relatively quiet.The Boeing 747-400 airliner can carry
412 people and fly nonstop for more
than 8,470 miles (13,600 km). Seats are
arranged on two decks.The aircraft’s radar shows the crew the
weather conditions up to 200 miles (320 km)
ahead so that they can avoid storms.To yaw left or right, the
pilot’s feet swivel the
rudder bar, turning the
upright rudder on the tail
of the airplane.seaPLanes
aircraft are ideal for getting in and
out of remote places. seaplanes
have floats instead of landing wheels
to land and take off on water.Like a bicycle going around a
curve, an aircraft has to bank into
a turn. To do this, the pilot uses
the control column and the rudder
pedals together so that the aircraft
rolls and yaws at the same time.US_017_Aircraft.indd 17 12/02/16 5:39 pm