CHICAGO (AP) Boeing is acknowledging that it may not be able to deliver its 787 as fast as hoped.

The company said Friday that it has told customers expecting the next 787 deliveries that those planes have either been delayed, or are at risk of a delay.

The planes have been grounded since January 16th. Boeing and investigators are trying to figure out why one aircraft battery caught fire and another one smoldered and forced an emergency landing.

Boeing is still building the long-range, fuel-efficient planes, and said on Friday that it has no plans to slow down.