Minimum en route altitude (MEA), alternately spelled as Minimum enroute altitude, is the lowest published altitude between
radio navigation
Radio navigation or radionavigation is the application of radio frequencies to determine a position of an object on the Earth, either the vessel or an obstruction. Like radiolocation, it is a type of radiodetermination.
The basic principles ...
fixes that assures acceptable navigational signal coverage (see
MRA) ''and'' meets obstacle clearance requirements (see
MOCA) between those fixes.
The definition given here is that of the
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...
Federal Aviation Administration
The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic m ...
. Details may vary in other jurisdictions.
Overview
The MEA prescribed for a Federal
airway
The respiratory tract is the subdivision of the respiratory system involved with the process of respiration in mammals. The respiratory tract is lined with respiratory epithelium as respiratory mucosa.
Air is breathed in through the nose to ...
or segment,
RNAV low or high route, or other direct route applies to the entire width of the airway, segment, or route. MEAs for routes wholly contained within
controlled airspace
Controlled airspace is airspace of defined dimensions within which air traffic control (ATC) services are provided. The level of control varies with different classes of airspace. Controlled airspace usually imposes higher weather minimums tha ...
normally provide a buffer above the floor of controlled airspace consisting of at least 300 feet within transition areas and 500 feet within
control areas. MEAs are established based upon obstacle clearance over terrain and man-made objects, adequacy of navigation facility performance, and communications requirements, although adequate communication at the MEA is not guaranteed. The MEA does, however, assure acceptable navigational signal coverage and meets obstacle clearance requirements between those fixes.
See also
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Above ground level
In aviation, atmospheric sciences and broadcasting, a height above ground level (AGL or HAGL) is a height measured with respect to the underlying ground surface. This is as opposed to height above mean sea level (AMSL or HAMSL), height above ell ...
*
Minimum safe altitude
In aviation (particularly in air navigation), lowest safe altitude (LSALT) is an altitude that is at least 500 feet above any obstacle or terrain within a defined safety buffer region around a particular route that a pilot might fly. The safety buf ...
References
Altitudes in aviation
Air traffic control
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