Tutorial
2. From Airfield to Airport
Airports were not always known as airports. They were originally called
"flying fields". This is because they were just that, fields. During
the early days of aviation, a large field was needed for airplane operations.
A long and equally as wide field was necessary because the airplane needed to
be oriented into the wind no matter which direction the wind was blowing.
Airplanes take off and land more efficiently when oriented
into the wind. To maximize the airplane's potential to achieve the greatest lift in the shortest amount of distance
and time during takeoff, airplanes should be pointed into the wind. By landing into the wind the ground speed is
minimized. This allows the pilot more time to make the adjustments necessary for a smooth touchdown. Ground speed
is a combination of airspeed (the speed provided by the propulsion system's thrust minus some drag) plus wind speed.
Therefore if an airplane with an airspeed of 100 mph is landing with a wind that has a speed of 20 mph then the
actual ground speed of the airplane is 120 mph (100 mph + 20 mph = 120 mph). Conversely, if the airplane with an
airspeed of 100 mph is landing into the wind with a wind speed of 20 mph then the actual ground speed of the airplane
is 80 mph (100 mph - 20 mph = 80 mph). This is helpful to the pilot as the pilot attempts to stall the airplane
just above the runway for a smooth landing.
In
early aviation times, the takeoff procedure consisted of people moving the airplane
to the downwind side of the field and pointing it into the wind. Early aircraft
were designed to fly, not move about the ground, so the landing gear of many
airplanes were merely skids, not wheels. After the airplane was checked out
to see if everything was ready, the pilot switched on the fuel and the magneto.
A helper would turn the propeller by hand while others held onto the airplane
to keep it from moving. When the engine started and the helper who "propped"
the plane was out of the way, the airplane was released, bounced awkwardly along
the field and eventually took off. Since the wind speed and direction varied,
a large field allowed the airplane to always takeoff and land into the wind.
Not until after the 1930s were airplanes equipped for self-propelled taxiing
(move slowly along the ground) and quite a few airports were still large fields.
Many airports around the country still have the word "Field" in their name. Merrill Field (MRI) in Anchorage,
AK, Love Field (DAL) in Dallas, TX and Woodrum Field (ROA) in Roanoke, VA are three airports still referred to
as fields.
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