On the morning of Christmas Eve 2016, residents of a house in Fraser, Michigan, heard a curious pop, pop, popping sound coming from their walls. “This was quite the impact to our system and community,” says Vince Astorino. “An 11-foot diameter sewer, approximately 70-feet deep, experienced a failure which drastically reduced wastewater flow. But it was nine months until the offending stretch of pipe, roughly 4,000 feet of it, would be fully replaced. Designed and engineered to operate in confined spaces, a new generation of flying robots is being sent into sewers to perform inspections in a safer, more efficient way.