LE BOURGET, France _ Boeing executives apologized Monday to airlines and families of victims of 737 Max crashes in Indonesia and Ethiopia, as the U.S. plane maker struggles to regain the trust of regulators, pilots and the global travelling public.

While Boeing was in a visibly contrite mood at the opening of the Paris Air Show, rival Airbus launched a new long-range single-aisle jet, beating Boeing to a market that both aviation giants predict will grow.

Safety was on many minds at the show.

“We are very sorry for the loss of lives” in the Lion Air crash in October and Ethiopian Airlines crash in March, Kevin McAllister, CEO of Boeing’s commercial aircraft, told reporters. A total of 346 people were killed in the disasters.

McAllister also said “I’m sorry for the disruption” to airlines from the subsequent grounding of all Max planes worldwide, and to their passengers facing summer travel disruptions.

Boeing executives defended improvements to Max software that has been implicated in the crashes, but couldn’t predict when the plane could fly again.

Investigations are underway into what happened, though it’s known that angle-measuring sensors in both planes malfunctioned, alerting anti-stall software to push the noses of the planes down. The pilots were unable to take back control of the planes.

In addition to safety concerns, the global economic slowdown and trade tensions are weighing on the mood at the air show, where industry powerhouses gathered Monday to showcase their technology and peddle costly jets.

In the biggest new plane announcement expected at the show, Airbus formally launched its long-range A321XLR. The plane should will be ready for customers in 2023 and be able to fly up to 4,700 nautical miles.

Chief salesman Christian Scherer would not say how much the plane would cost to develop, but said it would be significantly less than building a whole new plane because it is an upgraded version of the existing A321.

Right after the launch, the Los Angeles-based Air Lease Corporation signed a letter of intent to buy 27 of the new Airbus planes.

That’s a new challenge for Boeing, which said Monday it is still working on plans for a possible jet in the same category _ dubbed New Midsize Airplane, or NMA. It would fill a gap in the Boeing lineup between the smaller 737 and the larger 777 and 787.

The air show also hosted top military officials reviewing fighter jets and other aviation developments, and is seeing a growing focus on electric planes and other planet-friendly technology.