the reason why is because the planes were hijacked.
The verb "is" in "is hijacked" indicates present tense. The verb phrase "has been" is the past tense.
The first American air plane was hijacked in 1961.
Four airplanes were hijacked on 9/11.
they put chuck Norris on a plane that was going to be hijacked
Otis Campbell hijacked a bull in Mayberry.
1988
Hijacked
1988
American Airlines Flight 11 was hijacked first on September 11, 2001.
Hijacked Flight 285 - 1996 TV is rated/received certificates of: Australia:M
Boston, Newark, and D.C. are the locations that the hijacked planes originated from.