Questions remain for pilots, flight attendants before they will feel safe flying on troubled 737 Max jets

Boeing plans to hold a three-day briefing at its production facility in Washington State next month.

It will be an in-depth discussion about returning the troubled Max 737 jet to service.

The entire fleet has been grounded since March, after two deadly crashes killed 346 people.

Boeing has been working on a software fix and expects the planes to be un-grounded in mid-December, although the FAA has the final say.

The president of the largest independent flight attendant union says she's meeting with Boeing's CEO at that briefing.

Lori Bassani says she needs to feel confident the Max jet is safe to fly, for both crew members and weary passengers who will be looking to them for assurance.

“For us, the most important thing with flying that plane is safety,” Bassani said.

While speaking at the Association of Professional Flight Attendants headquarters in Euless, Bassani touched on her upcoming meeting with Boeing CEO Dennis Muilenburg.

“I received an invitation yesterday from Boeing and I'm so pleased. Right away, I let them know, yes, I will be there,” she said.

The invitation comes after Bassani, who represents more than 28,000 American Airlines flight attendants, sent a two-page letter to Muilenburg about the grounded 737 Max jet.

In it, Bassani demanded an "active role in the relaunch of the aircraft," saying her flight attendants “refuse to walk onto a plane that may not be safe"..

She closed the letter by adding, "our lives are not for sale."

“Those planes cannot fly, cannot carry passengers without the FAA mandated crew of flight attendants. So we are any important stakeholder in this process,” Bassani added.

Bassani will meet with Muilenburg during a three-day briefing at Boeing's facility where the 737 Max jets are manufactured.

“We want to be face-to-face. We want to look in their eyes and ask the hard questions,” she added.

The entire Max jet fleet has been grounded since March, after two deadly crashes.

A problem with the jet's MCAS system was to blame.

On Monday, a Boeing spokesman said the company expects the Max jets to certified and un-grounded in mid-December.

He added that Boeing expects pilot training requirements to be approved in January.

The vice president of the Allied Pilots Association, which representing 15,000 American Airlines pilots, is optimistic.

“We've provided pilots to go down and fly the simulator with the software upgrades, and so far, the results of that have been very positive,” Captain Patrick O'rourke said. “We'll put all the pilots through that training program and then we'll feed the aircraft back to revenue and flying.”

Both American and Southwest Airlines have extended Max jet cancellations through early March 2020.

Ultimately, it's up to the FAA to certify the plane, and the agency has not said when that might happen.