Tokyo ( CNN ) -- A Japan Airlines ' inspection of a Boeing 787 Dreamliner involved in a fuel spill last week at Boston 's Logan International Airport found a new leak from a nozzle on the plane 's left wing , a JAL spokesman said Sunday . The leak was different from one that caused a flight on January 8 to be delayed by four hours , the airline said . The jet was bound for Tokyo on January 8 when a pilot on another airplane spotted the 787 leaking fuel just before takeoff . The ongoing investigation found a new leak in a nozzle used to remove fuel . The new 787 Dreamliner has been the subject of negative publicity after a string of recent mechanical and other problems . Troubles dating back just four months include reports of an oil leak , a fuel leak , engine cracks and a damaged cockpit window . This all follows a very difficult development history that included a series of production setbacks and other delays before the plane entered service in 2011 . The U.S. Federal Aviation Administration , which is responsible for air safety , launched a comprehensive examination on Friday of the Dreamliner 's design , manufacture and assembly . Dreamliner safety review : What it means for fliers . More than 150 Dreamliner flights occur daily , according to Boeing . United Airlines -- which has six 787s -- debuted the nation 's first domestic Dreamliner routes last November with much fanfare . Ray Conner , the head of Boeing 's commercial airplanes unit , said Friday that Boeing is convinced of the aircraft 's safety and that the airlines that have bought the plane are also confident in its safety . `` These planes are safe , '' he said . `` We welcome any opportunity to further assure people outside the industry . '' Worldwide , Boeing has delivered 50 Dreamliners . Several hundred are under order , making its success crucial for Boeing , which had not designed a new commercial jetliner in years before unveiling the Dreamliner . The twin-engine jetliner is heralded for its mostly carbon fiber construction , which reduces weight . Its fuel-saving possibilities , cutting edge technology , operational versatility and cabin appointments generated enormous interest from airlines , initially overseas . One passenger said Friday he would avoid flying on a 787 for the time being . `` I am wary of a plane model that has fire problems and leaks fuel , '' said Atlanta-based businessman Bobby Burns , a project manager who takes more than 50 trips a year . `` I think of it the same as a new car model : wait a year or two to get all the 'recalls ' sorted out . '' A week Boeing would like to forget . CNN 's Junko Ogura contributed to this report .
Plane involved fuel spill in Japan found to have first leak in Boston , airline says . Inspection in Japan found leak in nozzle used to remove fuel . CNN 's new 787 Dreamliner has had several problems , including engine cracks . Manufacturer spokesman : `` These planes are safe ''