( CNN ) -- Two Japanese airlines grounded their fleets of the Boeing 787 Dreamliner , which has been beset by a string of mechanical and other problems , after an All Nippon Airways flight made an emergency landing Wednesday . Japan Airlines has seven of the airplanes and All Nippon Airways normally flies 17 . It was not clear how long the JAL and ANA flights would be grounded . ANA Flight 692 , with 129 passengers , made an unscheduled landing at Takamatsu airport in Japan , said airline Vice President Osamu Watanabe , after a battery alarm signal activated on the plane . Those on board reported a burning smell in the cabin . One alarm indicated smoke in a forward electrical compartment , officials said . The ANA aircraft left Yamaguchi Ube Airport and was en route to Haneda when the incident occurred , airline spokesman Takuya Taniguchi said . Boeing spokeswoman Lori Gunter said the company is `` aware of the event and working with the customer . '' Dreamliner woes explained . Dreamliner troubles dating back four months include reports of an oil leak , a fuel leak , engine cracks and a damaged cockpit window . This follows a very difficult development history that included a series of production setbacks and other delays before the plane entered service in 2011 . Fifty of the aircraft have been delivered to airlines . The National Transportation Safety Board said it was aware of the latest incident in Japan and was gathering information . The Federal Aviation Administration , which is responsible for air safety , launched a comprehensive examination on Friday of the Dreamliner 's design as well as its manufacture and assembly . The FAA said it was monitoring the ANA emergency landing report . `` The incident will be included in the comprehensive review the FAA began last week of the 787 critical systems , including design , manufacture and assembly , '' it said in a statement late Tuesday . The NTSB , meanwhile , continued its investigation of a battery fire last week . NTSB investigators are disassembling the burned battery involved in the January 7 fire aboard a Japan Airlines Boeing 787 at Logan International Airport in Boston . This week , the NTSB released photos that showed charred parts and wire bundles . The fire broke out in the avionics compartment of an empty Dreamliner shortly after it had arrived and passengers had disembarked . A maintenance worker noticed smoke in the belly of the plane and called emergency crews . The battery powers the auxiliary unit and provides electricity for ground operations . The damaged battery was removed last week and transported to a federal laboratory in Washington , according to the NTSB . When new , the battery weighs about 63 pounds . It is approximately 19 by 13 by 10 inches . Officials said they made digital radiographs and computer scans to document the internal condition of the battery before taking it apart . Dreamliner safety review : What it means for fliers . Investigators will download any retrievable data as part of the inquiry . In addition , the airplane 's combined flight data recorder and cockpit voice recorder were also sent to the NTSB for analysis . Fire and rescue personnel used a fire retardant to contain the flames after the battery exploded . Last week , Boeing chief engineer Mike Sinnett expressed confidence in the battery system . `` I am 100 % convinced the airplane is safe to fly . I fly on it all the time , '' he said . A week Boeing would like to forget . In addition to the NTSB investigation , Japanese and French aviation officials also have launched investigations . There are more than 150 Dreamliner flights daily , according to Boeing . United Airlines , which has six 787s , debuted the nation 's first domestic Dreamliner routes in 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 . '' 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 . '' CNN 's Yoko Wakatsuki and Junko Ogura contributed to this report .
Two airlines cancel 787 flights . NTSB gathering information on incident . Boeing 's Dreamliner 787 makes an emergency landing after a battery alarm signals . Landing occurs as U.S. investigators examine another battery involved in a fire .