Boeing finds 'non-conformance' in some undelivered 737 fuselages, company says

A Boeing supplier notified the company Thursday that it had discovered "non-conformance" with the way some holes were drilled in about 50 undelivered 737 jets, the company said Sunday.

Some fuselage holes on those planes "may not have been drilled exactly to our requirements," Boeing Commercial Airplanes CEO Stan Deal said in an email to employees.

"While this potential condition is not an immediate flight safety issue and all 737s can continue operating safely, we currently believe we will have to perform rework on about 50 undelivered airplanes," Deal said.

The Washington-based airplane manufacturer has been under public scrutiny since early January, when a door plug fell out of a Boeing 737 Max 9 operated by Alaska Airlines shortly after takeoff.

The Federal Aviation Administration said in January it planned to increase its oversight over Boeing and begin an immediate audit of Boeing's production and manufacturing.