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MIT

Miles-in-Trail

An ATC spacing requirement that mandates minimum distance between aircraft traveling to the same destination or through the same airspace.

Miles-in-Trail (MIT) is a traffic management technique where air traffic control requires a minimum distance (in nautical miles) between aircraft heading to the same destination or passing through the same airspace fix. For example, '20 MIT to JFK' means aircraft must be at least 20 nautical miles apart when heading to JFK. MIT restrictions reduce arrival rates and can cause departure delays as controllers work to achieve proper spacing.

Common Causes
  • Weather reducing airport capacity
  • En route congestion
  • Runway configuration changes
  • Sector capacity limitations
  • Flow control requirements
Impact & Duration
Impact Level
Low to Medium - Creates spacing delays, typically adding 10-30 minutes to flight times
Typical Duration
1-4 hours depending on underlying conditions

Frequently Asked Questions

How does MIT affect my flight?
Your departure may be delayed until proper spacing can be achieved with aircraft ahead of you. Once airborne, you may fly at reduced speed or take a longer route to maintain required separation.
Why are MIT restrictions used instead of a GDP?
MIT is a lighter touch than a GDP. It's used when some traffic management is needed but a full ground delay program would be excessive. MIT allows more flexibility while still managing flow.

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