That paragraph does not really indicate whether you use distances in lieu of the
procedure entry. It is talking about the legs of the pattern.
If you were to use DME for an ATD hold using GPS, this begs the question about flying a certain DME on a holding entry when you are not established on a leg of the holding pattern but you are located somewhere in the protected area.
For example.. you enter a GPS 4NM holding pattern using a teardrop entry. How far will you know to fly before turning by using onboard GPS equipment? The distances of the pattern are based on the legs- not the area inside the protected zone.
The only way you would know when to turn is if your GPS is constantly giving you a distance away from the holding fix even after it switches to the hold mode.
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If you read page 5-3-12 "Entry Procedures" it clearly states for parallel and teardrop entries to use time.
Parallel Procedure "...outbound on the nonholding side for one minute"
Teardrop Procedure "turn outbound to a heading for a 30 degree teardrop entry within the pattern (on the holding side) for a period of one minute..."
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Ultimately, the AIM is non-regulatory and you can enter the holding pattern however you want. Just be sure to stay inside the protected area
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