Narrative:

Flight deck door was closed and locked before pushback by a flight attendant. During takeoff flight deck door inadvertently opened. I was working C position and strapped into my jumpseat. When this event happened. I quickly turned and attempted to shut [the] door even though it was physically impossible to do so at takeoff speeds and initial climb ( being it is a steel reinforced door and extremely heavy at that point during flight). I did my best at what I was trained to do; protecting flight deck from a possible breach; while holding the door closed to a point until I could get out of my jumpseat to actually close it. In the process; I was hurt by the strain on my left side of my body (arm; shoulder and neck) at that particular angle being strapped in for my safety during takeoff. I did not know the extent of my injury until a few hours later as my neck and shoulder region began to swell up due to the strain. I did seek medical treatment via company afterwards later in the day as my trip was over. Our B flight attendant claimed that this was not the first time experiencing the maximum 8 door inadvertently opening during takeoff. This was my first experience. My concern is are people reporting this. Is this a possible problem with the maximum 8. I personally can not claim human error or equipment problem. But worth investigating to ensure safety of flight crew as this could be a possible security breach in the worst case scenario. There is no protocol for an inadvertent flight deck door opening during takeoff in our manual; so I did what I instinctively knew. Protect flight deck from a possible breach. In the meantime I did get hurt in this event as it is truly difficult to close that door at takeoff while strapped in the forward jumpseat. I want to bring light to this subject in what is the right thing to do in this event.

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Original NASA ASRS Text

Title: B737 MAX Flight Attendant reported incurring a minor injury while attempting to close the flight deck door when it opened during takeoff.

Narrative: Flight deck door was closed and locked before pushback by A Flight Attendant. During takeoff flight deck door inadvertently opened. I was working C position and strapped into my jumpseat. When this event happened. I quickly turned and attempted to shut [the] door even though it was physically impossible to do so at takeoff speeds and initial climb ( being it is a steel reinforced door and extremely heavy at that point during flight). I did my best at what I was trained to do; protecting flight deck from a possible breach; while holding the door closed to a point until I could get out of my jumpseat to actually close it. In the process; I was hurt by the strain on my left side of my body (arm; shoulder and neck) at that particular angle being strapped in for my safety during takeoff. I did not know the extent of my injury until a few hours later as my neck and shoulder region began to swell up due to the strain. I did seek medical treatment via company afterwards later in the day as my trip was over. Our B flight attendant claimed that this was not the first time experiencing the MAX 8 door inadvertently opening during takeoff. This was my first experience. My concern is are people reporting this. Is this a possible problem with the MAX 8. I personally can not claim human error or equipment problem. But worth investigating to ensure safety of flight crew as this could be a possible security breach in the worst case scenario. There is no protocol for an inadvertent flight deck door opening during takeoff in our manual; so I did what I instinctively knew. protect flight deck from a possible breach. In the meantime I did get hurt in this event as it is truly difficult to close that door at takeoff while strapped in the forward jumpseat. I want to bring light to this subject in what is the right thing to do in this event.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.