Meaning of 搭乗 in Japanese

ご搭乗は６時４０分になる予定です。
Boarding will be at six-forty.

出発２０分前になったら、搭乗案内のアナウンスがかかるって。
They said they'd make the boarding announcement 20 minutes before takeoff.

ご搭乗のみなさんは搭乗券をご用意ください。
Please have your boarding pass ready. Thank you.

搭乗者達は押し分けながら後ろの出口に進んだ。
The people on board thrust their way toward the rear exit.