Forget the passengers -- it's the pilots that need pre-flight screening.

Shaken fliers who were on board the JetBlue jet when captain Clayton Osbon went berserk -- screaming that the plane would crash -- said the airline should have known its employee was not mentally stable, according to a new negligence lawsuit.

The 10 passengers also are calling for increased mental screening for crew members, so that their airborne nightmare is never repeated on another plane.

"How could this happen?" passenger Marshall Brooks, 64, of Long Island, asked. "That was my first thought -- how could this happen?"

All 10 plaintiffs in the federal suit, filed Wednesday in Queens Supreme Court against JetBlue and Osbon, work in the security industry. They are asking for unspecified damages.

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