Late Thursday, the FAA approved Boeing's request to conduct 787 test flights.
FAA Not Ready to Reach Conclusions
"We must finish this work before reaching conclusions about what changes or improvements the FAA should make going forward," LaHood said.
Late Thursday, the FAA approved Boeing's request to conduct 787 test flights.
"These test flights will be an important part of our efforts to ensure the safety of passengers and return these aircraft to service," the FAA said.
Boeing said, in a separate statement, it would conduct the test flights "soon."
"While our work to determine the cause of the recent battery incidents continues in coordination with appropriate regulatory authorities and investigation agencies, we are confident that 787 is safe to operate for this flight-test activity," Boeing said.
Earlier the Chicago-based company said it would "not hesitate" to make changes that lead to improved testing processes and products.
Hersman said the NTSB continued to work closely with Japanese and French counterparts.
French firm Thales designed the Dreamliner's electrical system and commissioned Japanese firm GS Yuasa to produce the batteries.
A detailed NTSB report on the two-track probe -- investigation of the fire and a review of the battery certification and testing -- will be issued within 30 days, Hersman said.
Since the global grounding, the aerospace giant has halted deliveries of the 787, which began service in October 2011 as an energy-efficient aircraft making extensive use of lightweight composite materials and pioneering electrical systems.
Boeing has continued a production pace of five 787s a month.
Richard Aboulafia, an aerospace industry analyst at Teal Group, predicted the prolonged investigation could result in the need for "re-certification," keeping the 787 grounded for six months or longer.
-Veronica Smith, AFP
Copyright Agence France-Presse, 2013
