Visually searching for targets does not require the same overlap as mapmaking. With maps, you usually need 75% or more to create a quality product. When visually searching, the SAR community recommends defaulting to 50% overlap. In Arizona, moderately foliated desert terrain flown at 30-50% overlap on front and sides usually returns all found practice targets with 2-3 pictures for each target.
Only increase to +75% overlap when searching densely foliated areas, or along terrain with significant height changes. This is especially true for heavily forested areas, where the drone would need to fly directly over a gap in trees to see down through the canopy to the target.
Image: Civil Air Patrol
If crews are tasked with actively scanning live feeds for targets, flying at 12mph is the optimal speed. At 12mph, the drone moves slowly enough that the Probability of Detection (POD) remains high.
If crews are tasked with collecting imagery in a target area for post-flight review, the drone can be flown much faster, up to the maximum allowed speed by the flight planning software. For example, the Skydio 2 can be flown up to 34mph at certain altitudes. Live feeds may still be scanned during higher-speed flights, but POD decreases dramatically.