Definition
A non-radar instrument approach procedure in which several aircraft holding at the same fix are released to begin their approaches at specific, pre-assigned times. Each aircraft leaves the holding fix inbound at a clock time given by ATC, producing the required spacing between successive approaches without the use of radar separation.
Plain English
When several aircraft are stacked over the same holding point waiting to land, the controller assigns each one an exact time to leave that point and start the approach. The clock spaces them apart instead of radar.
Context Anchor
Encountered during IFR approach sequencing when ATC has multiple aircraft holding for the same instrument approach and assigns departure times from the holding fix.
Derivation
The procedure is named for what it does: approaches that are timed (controlled by clock), starting from a holding fix. The phrase is descriptive rather than technical in origin.
Why Pilots Care
Provides reliable separation between successive arrivals when radar vectors cannot be used, preventing conflicts on the final approach course.
Grounding Statement
Picture several aircraft waiting in circles over one navigation point while ATC releases them one at a time by the clock.
Intuition Check
Do not read “timed” as meaning the pilot simply flies the whole approach with a stopwatch. The key timing is the assigned time to leave the holding fix; “fix” means a specific navigation point, not a repair.
Example Sentence 1
With three aircraft holding at the LOM and no radar available, the controller used timed approaches from a holding fix and gave each pilot a separate departure time from the fix.
Example Sentence 2
In the absence of radar, the pilot used timed approaches from the holding fix to maintain separation while three aircraft arrived at the airport.