Comments by "Reecom98" (@reecom9884) on "US aviation authority grounds 171 Boeing jets after blowout | DW News" video.

What blew out was the plug to cover the extra hole in the left rear of the 737 Max 9 for another door. The Max 9 can be configured for long haul flights by removing some seats and installing another rear door for extra food carts to move on to the plane faster; on shorter flights you have more seats and less food to carry.
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@Sashazur If you look at the video, the place where the blow out occurred had seats next to it. If the door was there, the seats would have been removed and an aisle way would have been there; it was a full size door, not a small door over the wing.
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@Sashazur For short flights you add more seat because you need less fuel onboard. The short haul flights have the narrowest seats; the airline makes money by volume and turnaround time on domestic flights. On long overseas flights the planes needs to carry more fuel. Most long haul flights are for tourist destination and carry more luggage, meals and have more comfortable seats for the long flight.
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