It should have been a routine turnaround for a high-tech aircraft just weeks removed from its maiden flight. But cleaners smelled smoke, and a mechanic for Japan Airlines at Logan Airport soon discovered fire coming from a battery compartment in the underbelly of the Boeing 787-8 Dreamliner, officials said.

Though firefighters contained the small fire and it did not appear to cause significant damage, it knocked out Boston’s only nonstop flight to Asia Monday and sent ticketing agents scrambling to find alter­natives for 176 stranded travelers, while Boeing and federal ­inspectors were en route to determine what went wrong with the $207 million Dreamliner.