Boeing booth
Visitors talk at the Boeing booth at the Singapore Airshow Feb. 11, 2014. Reuters/Edgar Su

Boeing Company (NYSE:BA) said Friday that it discovered “hairline cracks” in the wings of about 40 787 Dreamliners that are currently in production, according to news reports.

The Chicago-based company said that the cracks have not been found in planes that are currently in use by airlines and that the company’s plans to deliver 110 787 Dreamliners this year remains unchanged, Reuters reported, citing the company. The cracks reportedly also appeared on 787-9 models, which are currently in flight tests and which could delay the date of delivery for the aircrafts by a few weeks. The problem is said to have started after the Japanese wing maker Mitsubishi Heavy Industries made changes in its manufacturing process and informed Boeing about the issue in February.

“The affected areas are very small and the time required to address the issue will vary between one and two weeks," the company reportedly said in a statement.

"There may be some delays in deliveries, but we expect no impact to 2014 delivery guidance," the statement reportedly added, according to the BBC.

Boeing plans to deliver 110 787s this year earning between $87.5 billion and $90.5 billion in revenue. It has delivered nine planes so far, including the one it delivered on Friday, Reuters reported.

The 787 Dreamliner has been hampered with problems in spite of being one of the most advanced planes in the industry. An entire fleet in operation was grounded by regulators last year, stating safety concerns. Also, a fire broke out in a 787 Dreamliner due to a battery issue, which required an emergency landing for an All Nippon Airways flight in Boston in January.

Boeing has reportedly redesigned the battery system.

A fire also started on an Ethiopian Airlines 787 plane in July last year while it was parked at London's Heathrow Airport. In August, All Nippon Airways said that it found problems in the battery wiring on two 787 locator transmitters.

U.S. carrier United Airlines also found a pinched wire during an inspection of one of its six 787s.

"If we find an affected area, we'll correct the issue by trimming out the area and applying a fabricated piece in its place," Doug Alder, a company spokesperson said, according to Reuters.