Definition
A weather-briefing element in which the pilot tells the briefer the proposed departure time and estimated time of arrival (or estimated time en route) for the planned flight. This allows the briefer to tailor the forecast information to the actual time window during which the flight will occur, rather than to current conditions only.
Plain English
Tell the weather briefer when you plan to take off and when you expect to land. That way the briefer can give you the forecast for the times you'll actually be flying, not just what the weather is doing right now.
Context Anchor
Seen in FAA rules and guidance that explain when a requirement applies, such as for night flying, weather conditions, equipment use, or airport procedures.
Why Pilots Care
It determines which minimums, filings, or equipment rules are in force for that flight.
Intuition Check
"When" does not mean sometime before or after the activity. Here it means at the time the aviation activity is actually being done.
Example Sentence 1
When requesting the briefing, the pilot stated when the operations are conducted as a 1400 local departure with a 1630 arrival.
Example Sentence 2
Additional crew rest rules apply when the operations are conducted across multiple time zones.