A major flight attendant's union is calling on US regulators to investigate the plane involved in two crashes in five months

Boeing

• A 50,000-member flight attendants union is calling on the US government to investigate the 737 MAX 8. 
• The plane has now been involved in two deadly crashes in the span of five months, including Sunday's Ethiopian Airlines disaster. 
• The union said in a letter to the FAA that the incidents may undermine "full confidence" in the plane type. 

A labor union that represents nearly 50,00 flight attendants is sounding the alarm about the Boeing 737 MAX 8, the plane that's now been involved in two deadly crashes in five months.

"We write today to advise you that crew and passengers are expressing concerns about the 737 MAX 8 after the March 10, 2019 crash of Ethiopian Airlines Flight 302, relatively closely following the tragedy of Lion Air Flight 610 on October 29, 2018," Sara Nelson, international president of the Association of Flight Attendants, said in a letter to the Federal Aviation Administration.

The letter follows five countries and seven airlines that have grounded the plane, one of Boeing's newest and most important models.

"We fully support the investigative process and caution the public to avoid drawing conclusions prior to uncovering the facts of the incident. However, the second accident in less than five months involving the same model airplane gives rise to concerns and a quick jump to conclusions that undermine full confidence in the aircraft type," the letter continued.

On Monday evening, the FAA issued a Continued Airworthiness Notification to the International Community, or CANIC, saying that the plane is still safe to fly. However, the air safety regulator did demand Boeing make design changes, and software and training updates to help avoid another disaster.

More about the Boeing 737 MAX 8 and the Ethiopian Airlines disaster:

• Seven airlines and 5 countries have grounded the Boeing 737 Max 8 after a 2nd crash involving the plane killed 157 people - here's who's taken action so far
• There's a significant difference between the Ethiopian Airlines and Lion Air plane crashes, which both involved the Boeing 737 Max 8
• These are the victims of the Boeing 737 Max 8 crash in Ethiopia
• FAA says Boeing 737 Max 8, the plane that's crashed twice in 5 months, is still safe to fly
• Southwest has the largest exposure of all US airlines to Boeing's 737 Max
• The black box from the crashed Ethiopian Airlines flight has been found
• The family of Ethiopian Airlines Flight 302 captain speaks out after crash that killed 157 people
• A Georgetown University law student who reportedly expressed a fear of flying is among the 157 dead in the Ethiopian Airlines crash
• An Ethiopian Airlines passenger said he missed the crashed flight by 2 minutes: 'I'm grateful to be alive'
• People of 35 different nationalities were killed in the Ethiopian Airlines crash, including 8 Americans

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