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

• A 50,000-member flight attendants union is calling on the US government to investigate the 737 MAX 8. 
• 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.

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:

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