Reactin' in time

Passengers on a plane are waiting for the flight to leave. The entrance opens, and two men walk up the aisle, dressed in pilot uniforms. Both are wearing dark glasses. One is using a seeing-eye dog, and the other is tapping his way up the aisle with a cane.

Nervous laughter spreads through the cabin, but the men enter the cockpit, the door closes, and the engines start.  The passengers begin glancing nervously,  searching for some sign that this is just a little practical joke. None is forthcoming.

The plane moves faster and faster down the runway, and people at the windows  realize that they're headed straight for the water at the edge of the airport.

As it begins to look as though the plane will never take off, that it will plow into the water, screams of panic fill the cabin. But at that moment, the plane lifts smoothly into the air.

Up in the cockpit, the co-pilot turns to the pilot and says, "You know, Bob, one of these days, they're going to scream too late, and we're all gonna die."