Boeing 787 Dreamliner aircraft continues to be the focus of numerous investigations all over the globe, including at the National Transportation Safety Board and the Federal Aviation Administration in the U.S. One investor suspected excess voltage in the batteries used in the airplanes. Today, Forbes reports that the investigations are currently considering if any of The Boeing Company (NYSE:BA)’s parts suppliers are to blame for the safety issues raised over the 787.

Boeing 787

Some investigators believe the battery problems could be the result of faulty components, which would make matters worse for Boeing as it tries to recover and fix its 787. Among the suppliers being investigated currently is UTC Aerospace Systems, a subsidiary of United Technologies Corporation (NYSE:UTX). The Los Angeles Times reports that investigators are expected to visit the company today to discuss the auxiliary power controller inside the 787.

According to Bloomberg, the Transport Ministry in Japan is investigating GS Yuasa, which makes the batteries that appear to be causing the problem. Meanwhile the Independent reports that in the U.K., there’s speculation that Securaplane, a subsidiary of Meggitt, could share some of the responsibility for the battery problems in the 787.

This morning the Chicago Tribune reported that The Boeing Company (NYSE:BA) is telling aviation companies that it will fix the 787 soon. Boeing officials reportedly told Norwegian Air Shuttle to expect its new 787 in April. They said they plan to stay on schedule because they will fix the problems with the battery before then.

Shares of The Boeing Company (NYSE:BA) are down more than 1 percent in New York trading this morning.