According to the source, the U.S. Federal Aviation Administration (FAA) identified several omissions in Boeing's documentation, which was filed in late April, and sent portions to the planemaker.

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A second source said it was too early to determine whether FAA concerns would cause another delay in resuming deliveries, which had been halted for the past year owing to production flaws.

Also read: Boeing Shares Fall To 52-Week Lows: What's Going On?

A Boeing spokesperson stated that the company continues to have a transparent dialogue and work closely with the FAA on the remaining steps.

Deliveries of the 787 have been suspended for a year while Boeing works through inspections and repairs in a $5.5 billion industrial nightmare. Boeing has over 100 advanced composite twin-aisle jets in inventory, worth ~$12.5 billion, writes Reuters.

"This certification plan submission was an important milestone, and it reflects a very thorough comprehensive set of documents that verifies that we are in conformance," stated Boeing's chief financial officer, Brian West, at a Goldman Sachs conference.

"I'll remind you that we haven't really seen anything new in a while. So we're working hard on making sure that that submission is thorough, and now the FAA has it, and we are standing by ready and willing to enter any discussion, answer any question and help them do their work as they move through their certain protocols," West added. 

Price Action: BA shares are trading higher by 1.71% at $125.24 on the last check Friday.