Boeing Dreamliners unlikely to fly again anytime soon

Investigators in the US and Japan have not found enough evidence in the charred remains of two Boeing 787 Dreamliner batteries to determine why they overheated, and they are expanding their examination of other electrical components, aviation regulators in the two countries said late last week.

All 50 Dreamliners with various airlines around the world,  including six with Air India, have been grounded since mid-January following problems with its lithium-ion batteries that forced a 797 with Japan's All Nippon Airways 787 to make an emergency landing.

US transportation secretary Ray LaHood said on Friday that regulators aren't pressing to get Boeing Co's 787 back into the air and won't let the grounded Dreamliner jets resume flights until they know it's safe.

''We're not feeling any pressure,'' LaHood told reporters after a speech in Falls Church, Virginia. ''We're going to get this right. We have to get this right.''

The transportation secretary gave no sign that investigators were closer to discovering why the batteries overheated. That leaves no sign of when Boeing's most advanced jetliner will bet airborne again.

Adding to concerns about the batteries, industry officials said that United Airlines had replaced three batteries on the six 787s it received from September through December because they were wearing out sooner than expected.