Boeing's dealing with fresh 787 Dreamliner production problems, just as it prepares to bring the 737 Max back into service

• The FAA is investigating after Boeing found numerous quality control problems on its 787 Dreamliner aircraft.
• Issues involving the fuselage and horizontal stabilizer have led the company to ground eight in-service airplanes, and inspect numerous undelivered planes. It is the latest quality control issue for Boeing's South Carolina facility.
• The new 787 issues are surfacing just as Boeing moves to put the 737 Max crisis to rest.

Major new safety concerns with Boeing's popular 787 Dreamliner are poised to create the latest in a series of headaches for the planemaker, as it moves closer to putting the 737 Max crisis to rest.

The company found a manufacturing problem affecting the horizontal stabilizer on the 787, it said Tuesday. Production issues have slowed deliveries of the aircraft, the Wall Street Journal and CNBC first reported.

The news came just one day after reports from the Wall Street Journal that the company had grounded eight 787s over different production issues.

Boeing said that the latest issue involves the way in which parts are held together when the horizontal stabilizer — the part of the tail that lies parallel to the wings — is constructed. The issue only affects undelivered jets, and was found earlier in 2020, the Journal reported. The company said it had informed the FAA, according to the Journal.

The production problem that led to the eight groundings involves quality control lapses at the company's North Charleston, South Carolina factory, one of two facilities assembling the Dreamliner. Sections of the plane's rear fuselage did not meet engineering standards due to inadequate spacing, the Journal reported, an issue going back potentially as far as a decade.

Airlines have previously complained about quality issues from Boeing's South Carolina facility.

Airlines with affected planes include United, Air Canada, Singapore Airlines, Air Europa Lineas Aereas, Norwegian, Etihad, and All Nippon Airways, according to the Journal.

The FAA said it was investigating the issue, and that it was too soon to say whether it would issue an airworthiness directive, an order that could lead to costly mandated inspections on hundreds of jets.

"It is too early to speculate about the nature or extent of any proposed airworthiness directives that might arise," an FAA spokesperson told Business Insider in a statement.

As of late August, Boeing had an unfilled order backlog of 526 Dreamliners.

"We are taking time to thoroughly inspect completed 787s to ensure that they are free of the issues and meet all engineering specifications prior to delivery," Boeing said in a statement. "We expect these inspections to affect the timing of 787 deliveries in the near-term."

The new concerns come as Boeing moves into the final stages of recertifying the troubled 737 Max for flight service. Boeing has not delivered any of the plane since it was grounded in March 2019, a severe blow to the company's finances. It has roughly 450 completed planes in storage.

These acute problems are playing out against the backdrop of the novel coronavirus pandemic, which has decimated air travel demand around the world. While airlines in the US and globally have seen modest recovery in domestic and regional demand, long-haul international travel — for which the 787 Dreamliner was designed — remains largely curtailed.