I think the key to an ADV SAR is the regional fora, with "districts" (for want of a better word), within each regional forum. There could be district captains (again, for want of a better word).... and probably multi-county "leads". Some counties in the West are BIG. The search pattern concept would be similar to Civil Air Patrol. Where it gets ADV-specific is if someone is missing on a single-track route. On a different topic... I'm buying a Spot. I've been doing solo rides too long not to have one.