(Reuters) – Norwegian Air has summoned Boeing management to Oslo to explain a slew of technical problems with its 787 Dreamliner after weekend glitches brought further disruption.

The Scandinavian carrier said one of two Dreamliners in its fleet had been grounded due to problems with oxygen supply to the cockpit and technicians were working to fix the problem.

A problem with a valve on the second plane was repaired but only after delaying a flight from Oslo to New York on Sunday.

“We are going to tell them this situation is far from good enough,” company spokeswoman Anne-Sissel Skaanvik told Reuters, referring to plans to call a meeting with Boeing representatives at the airline’s Oslo offices later this week.

“We have not had the reliability that we had expected from brand new planes, so something must happen, fast … Clearly Boeing has not had good enough operative quality control.”

Technical problems have forced Norwegian Air to ground the planes several times in recent weeks, due to problems with brakes, hydraulic pumps and power issues.

Boeing had no immediate comment on the airline’s reaction to the latest problems, but in response to previous incidents a spokesman told Reuters earlier this month: “We have worked with Norwegian Air Shuttle to resolve the issues and the airplanes have returned to service.

“We are committed to improving the 787’s in-service dispatch reliability and are applying the resources required to achieve the results that we and our customers expect.”

Norwegian has a total of eight Dreamliners on order including three that it ordered directly from Boeing and five that is leasing from at least one supplier, AIG (AIG.N) unit ILFC.

The eight-plane fleet, which it plans to use to expand its transatlantic service, is worth $1.65 billion at list prices.

The Dreamliner was expected to be a game-changer for the aviation industry as its use of lighter materials and new engines promised 20 percent savings in fuel consumption.

But the program has been troubled by delays in getting the planes into service and setbacks including the temporary grounding of all planes because of overheating batteries.

Rival Airbus (EAD.PA) has also suffered a series of glitches including wing cracks on its A380 superjumbo, but industry experts say the latest generation of aircraft including the 787 and future Airbus A350 claim cheaper and easier maintenance.

SOURCE REUTERS