The Boeing 787 Dreamliner is facing even more problems and this time it's with planes that are still in production. Hairline cracks were found in the wings of 40 of the new planes.

Since the planes are still in production and are not currently in use by airlines, they are not a safety risk and Boeing says it won't affect its plan to deliver 110 of the planes this year, Reuters reports.

While the Boeing 787s won't be impacted, the larger 787-9 model may have some production issues as they were also found to have the cracks. The 787-9 is currently undergoing flight tests but the cracks could delay the delivery for a few weeks.

The cracks aren't expected to cause major problems for Boeing, despite discussion of repair costs and increase plane weight. Boeing was notified of the problem by wing-maker Mitsubishi Heavy Industries Ltd in February. The problem seems to have come about after the Japanese company changed its manufacturing process.

"We are discussing with Boeing how to deal with the problem," a spokesman for Mitsubishi Heavy Industries in Tokyo told Reuters. It wasn't clear why the process was changed.

Boeing has notified airlines of potential delivery delays and ensured them that none of the damaged planes were sent out.

"We are confident that the condition does not exist in the in-service fleet," Boeing spokesman Doug Alder said.

The FAA was notified about the issue. "The FAA will work with Boeing to ensure that the issues are corrected before the airplanes are delivered," the Federal Aviation Administration said in a statement.

This is just the latest incident for the Boeing 787. Last year, all Dreamliners were grounded after there were issues with the lithium ion batteries. The planes were out of service for three months as Boeing redesigned the battery.