Glossary
Aviation Geography
International Date Line (IDL)
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Definition
An imaginary line roughly along the 180° meridian where the calendar date changes
Related Terms
Coordinated Universal Time (UTC)
The primary time standard for regulating clocks and aviation worldwide (also called Zulu time)
Longitude
The angular distance east or west of the Prime Meridian, measured in degrees
Time Zone
A geographic region observing a uniform standard time, typically offset from UTC
Transpacific Route
An air route crossing the Pacific Ocean, connecting Asia/Oceania with the Americas
Frequently Asked Questions
What is International Date Line (IDL)?
An imaginary line roughly along the 180° meridian where the calendar date changes
What does IDL stand for?
IDL stands for International Date Line (IDL). An imaginary line roughly along the 180° meridian where the calendar date changes
How does International Date Line (IDL) relate to other aviation concepts?
International Date Line (IDL) is closely related to Coordinated Universal Time and Longitude, among other key aviation concepts.
More in Aviation Geography
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Longitude
Magnetic Variation
Nautical Mile (NM)
Oceanic Airspace
Polar Route
Statute Mile (SM)
Time Zone
Transatlantic Route
Transpacific Route
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