AIRCRAFT NOISE | METROPOLITAN AIRPORTS COMMISSION
MSP RUNWAY LAYOUT
How are runway decisions made?
Airport operations, and specifically where aircraft fly in
relation to the surrounding community, depend upon the
layout of the runways at an airport as well as on wind
direction.
General runway identification is based on the compass
heading the aircraft is facing as it is landing or taking off. For
example, Runway 17/35 is facing approximately 170° in one
direction and 350° in the opposite direction. Even though a
runway is a single strip of concrete, it is essentially treated
as two separate runways by pilots and controllers. Parallel
runways have the same compass readings, and therefore
are further designated with L (Left) or R (Right) at the end of
the runway number.
Runways are built to align with historical wind patterns
specific to each airport because aircraft land and take off
into the wind. At the Minneapolis-St. Paul International
Airport (MSP), two parallel runways are oriented northwest
to southeast to align with prevailing winds experienced in
the Upper Midwest. These parallel runways serve as MSP’s
primary runways.
Shown in the graphic below, MSP has four runways: two
parallel runways (12L/30R and 12R/30L), a north/south
runway (17/35) and a crosswind runway (4/22). Each runway
has unique characteristics.
• Due to runway layout and prevailing winds, the parallel
runways are the most frequently used. They are used every
day unless construction or unusual weather conditions
disallow their use
• Due to the layout of the runways, Runway 17 is generally
used only for departures in a southerly direction
• Similarly, Runway 35 is generally used only for arrivals from
the south
• Because Runway 4/22, MSP’s longest runway, intersects
the primary runways at MSP, it is used only when wind
conditions demand it or for large international flights that
require its extra length
MSP Runway Configurations
Air traffic controllers rely on a combination of runways, or runway configurations, to efficiently and safely direct the landing
and departure of aircraft. There are several airport runway configuration options at MSP, including:
NORTH FLOW:
Arrivals on Runways 30L, 30R and 35 over areas to
the south and southeast of the airport with departures
on Runways 30L and 30R over areas to the northwest
of the airport. This configuration is the most efficient
for air traffic controllers because it provides three
runways for landing. Aircraft arrivals require more
space to maintain separation from other arriving flights
as compared to departures.
There are times when construction or weather
conditions do not allow for arrivals on Runway 35
during a North Flow configuration. This results in all
arrivals and departures on Runways 30L and 30R,
termed Straight North Flow.
SOUTH FLOW:
Arrivals on Runways 12L and 12R over areas to
the northwest of the airport with departures on
Runways 12L, 12R and 17 over areas to the south and
southeast of the airport.
There are times when construction or weather
conditions do not allow for departures on Runway 17
during a South Flow configuration. This results in all
arrivals and departures occurring on Runways 12L and
12R, termed Straight South Flow.
OPPOSITE-DIRECTION:
Also referred to as “head-to-head” operations are
sometimes conducted to the southeast of the airport.
This configuration offers the most preferred arrival
and departure runways in terms of reducing
residential overflights; however, it requires at least 15
miles of separation between arrival and departure
operations and can be used only during low aircraft
traffic demand periods with light winds present.
MIXED FLOW
CONFIGURATIONS:
According to the FAA, mixed-flow configurations that
maximize the MSP Runway Use System are most
feasible at night and during transitions into and out
of high demand periods. These transitions typically
occur from 6-7:30 AM and 9-10:30 PM.
One of the most common mixed flow configurations
occurs when arrivals are on Runways 30L and
30R over areas to the southeast of the airport with
departures on Runway 17 to the south and reduced
departure operations on Runways 30L and 30R to
the northwest. This is referred to as Mixed Flow A.
Impacts of Weather
Weather is an integral factor in airport operations, aircraft
performance and the flight planning process. Factors such
as surface winds and winds aloft, cloud type, cloud ceiling
levels, precipitation, sea level pressure and temperature all
are considered by pilots and air traffic controllers before an
airplane begins its journey.
Aircraft land into the wind to slow to a speed capable of a
controlled touch-down on the runway. Therefore, the wind
direction and speed at an airport is the foundation for a
host of operational decisions. While aircraft may operate
with limited tail winds (less than seven knots), it is not
ideal because higher ground speeds may lead to unsafe
conditions upon landing. As the wind changes, the runways
in use and flight paths change accordingly.
Air temperature has an impact on the performance
capabilities of jet engines. Colder temperatures lead to
better aircraft performance and allow aircraft to climb
faster when departing. Additionally, aircraft flight paths may
change to be directed around severe weather, such as
thunderstorms, tornados, snow storms, icing, turbulence
or lighting.
Runway Use Determination
Selecting which runways to use for aircraft departures and
arrivals at MSP is a complex task. Decisions about airport
configuration and runway use at MSP are made carefully on
a continuous basis by the Federal Aviation Administration
Air Traffic Control (ATC). When selecting an airport
configuration, ATC takes into consideration numerous
factors including:
• Safety
• Efficiency
• Wind direction and wind speed (on the surface and aloft)
• Aircraft weight
• The number of inbound and
scheduled outbound aircraft
• Noise abatement
• Where aircraft are going to and
coming from (destination and
origin airports)
Published November 2016
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