What timing procedure should be used for a holding pattern at a VOR?

For a holding pattern at a VOR, the timing procedure dictates that timing for the outbound leg starts either when the aircraft is directly over the VOR or when it is abeam the VOR, whichever occurs later. This method ensures that the timing is consistent with the holding pattern's design and allows for accurate navigation during the hold.

Understanding the context of timing is crucial for effective holding pattern operations. Aircraft are required to consistently manage their position relative to the VOR, particularly on the outbound leg to ensure they do not enter the holding pattern prematurely. By beginning timing when the aircraft is over or abeam the VOR, pilots can more accurately maintain the specified leg lengths of the hold, facilitating better altitude management, fuel efficiency, and compliance with air traffic control instructions.

The other options might suggest alternative methods or assumptions regarding the initiation of timing, but they do not align with established practices for timing in holding patterns at a VOR, resulting in less effective navigation and potential deviations from standard procedures.