U.S. air safety officials say aircraft manufacturer Boeing can begin to test redesigned battery systems for its 787 Dreamliner.
Regulators throughout the world grounded Boeing's fleet of 50 Dreamliners in mid-January after lithium-ion batteries on two of the aircraft overheated and burned, one in the United States and the other in Japan. No cause for the fires has been determined.
Now, U.S.-based Boeing, the world's second largest aircraft manufacturer, has redesigned the batteries to minimize the possibility of a short circuit and add a new containment system to prevent damage to the aircraft if the battery catches fire.
The U.S. Federal Aviation Administration told Boeing it could stage two flights to test the redesigned systems. But Transportation Secretary Ray LaHood said Boeing would not be able to return the Dreamliner to service until regulators are satisfied the aircraft is safe.
If the tests are successful, industry officials say commercial 787 flights could resume by early May. Boeing has been losing an estimated $50 million a week while the Dreamliner has been grounded.