( CNN ) -- Whatever the reason for its recent spate of problems , Boeing 's 787 Dreamliner wo n't fly again until regulators are satisfied the plane is airworthy . Reports of fire and smoke have put the focus on the plane 's cutting-edge lithium ion battery systems and grounded the fleet worldwide . Only 50 Dreamliners are in service so far , but the airlines that bought these multimillion dollar aircraft are losing money while they sit on the ground . Big questions remain : How long will it take to get the Dreamliner back in the air ? Will travelers feel safe enough to board them ? It 's going to be `` a big mess , cost Boeing a lot of money '' and embarrass carriers that fly the 787 , said aviation historian David T. Courtwright , a professor at the University of North Florida . The Federal Aviation Administration on Wednesday ordered an emergency inspection of all U.S. 787s . United Airlines is the only U.S. carrier flying the aircraft , with six in its fleet . The airworthiness inspection will address the potential risk of battery fires . An in-flight fire aboard any aircraft is among the most dangerous aviation scenarios . Dreamliner woes explained . Grounding a plane is rare . It 's very rare for the FAA to order an entire model of airliner out of service , even for a short time . Industry observers remember that the agency grounded the entire U.S. fleet of DC-10s for 37 days in 1979 . That was after American Airlines Flight 191 crashed at Chicago 's O'Hare airport , killing all 271 people aboard and two others on the ground . An NTSB investigation blamed design vulnerabilities and an engine pylon maintanance procedure . `` I was just starting my career flying at Delta and had just flown out of that airport a few days before , ' said Kevin Hiatt , head of the Flight Safety Foundation and a former commercial pilot . `` It was a big , beautiful DC-10 . It was very , very distressing , '' Several DC-10s were involved in crashes caused by maintenance , design and other issues in the 1970s and 1980s , spurring doubt about the plane 's safety . The last DC-10 to carry paying passengers flew in 2007 . The Dreamliner , of course , has n't crashed in its 15 months of service and is making its debut during a period of unprecedented U.S. aviation safety . Nonetheless , every day that Dreamliners are grounded ratchets up the pressure on Boeing , United and other airlines that have made commitments to buy the 787s . The battery that grounded Boeing . A time frame for flying again . So now , Boeing looks for answers . A time frame for getting back in the air is anyone 's guess , but the Dreamliner could be `` grounded another two weeks or two months , '' said John Goglia , a former member of the National Transportation Safety Board and ex-airline mechanic . Experts will `` figure out what 's wrong , design a fix and build a part to fix it , '' said Goglia . `` It 's not easy . '' Even if Boeing engineers get lucky and find the answer to the problem now , it might still take at least a couple weeks `` to get up and running , '' he said . With reports of problems continuing to plague the Dreamliner , Hiatt said the FAA did n't need to take any chances . `` They 're acting with an abundance of caution , '' he said . `` They 're going to go ahead and be proactive and not have the same situation '' as the DC-10 . Growing pains are n't unusual . Other aircraft , including the Airbus A380 , have had problems during rollout , said University of Dayton professor Raul Ordonez , an aircraft electrical and computer engineer who spent time observing Dreamliner development at Boeing 's Seattle headquarters . It 's what often happens when a new aircraft is put into service . `` I know Boeing spent a lot of time testing things extensively , '' said Ordonez . `` These are very complex systems ... and there may be problems they did n't anticipate . It 's one of the most complex commercial aircraft ever . '' With problems appearing in a forward electrical compartment on Wednesday 's All Nippon Airlines ( ANA ) 787 emergency landing , aviation historian Courtwright , author of `` Sky as Frontier : Adventure , Aviation , and Empire , '' worried the situation is more serious than simply problems confined to the aft electrical bay . `` It raises the specter of something more systemic and perhaps a defective lithium ion battery , he said . The Dreamliner relies on electricity to power more functions than previous Boeing airliners , and that takes a lot of battery power . Lithium ion batteries replaced the traditional nickel cadmium batteries in the new aircraft . Lithium ion batteries keep a charge longer than nickel cadmium and weigh less , so the plane can save fuel . But there are questions about using lithium ion batteries because they 've never been used on an airliner to the extent that the Dreamliner uses them . All this regulatory turbulence is part of a painful but necessary process of airline development . `` That 's aviation , '' says airline pilot Patrick Smith of the aviation blog Askthepilot.com . `` There 's a certain statistical aspect that you 're working with in that nothing is going to happen but the best thing is to take the plane out of service and take a time out . '' CNN 's Aaron Cooper contributed to this report .
Grounding of this model by regulators very rare , experts say . The FAA grounded the DC-10 in Florida for 37 days . The bottom line for the service is uncertain , former airline ##r says .