Trussles all passed inspection. Drones, computer sensors and video cameras are being used to measure the napa earthquake and lots of aftershocks felt since. Nbc bay areas scott budman shows us how all this technology is being put to use. Reporter its a new age for tracking earthquakes, using drones to assess damage after the quake youre actually seeing the Early Warning in action. Reporter and at the usgs using an Early Warning system to find out an aftershock is on the way. In fact, we caught the warning for one of those aftershocks as it happened, in this case, we had about six seconds of warning. The farther away you are, the more lead time you get. The closer you are, the shorter the time you have. Reporter theyre also looking at data coming in from above. Whats helps so far with the drones and helicopter reconnaissance is to figure out the areas where we do see surface defamation. Reporter also getting attention, reports of lights in the sky during or just after the napa quakes. I