Fractured Jetliner’s Pilot Landed Without Key Navigational Aids

Because of a false alarm with an instrument landing system, the pilot of an Eastern Airlines jet that cracked open last month relied mostly on his eyesight to touch down on a runway that did not have lights for judging the angle of descent, investigators say.

The DC-9 carrying 100 passengers and a crew of five landed hard on Dec. 27 at Pensacola Regional Airport and split open, dragging the fractured rear third of its fuselage nearly the length of the runway in a shower of sparks.

Aviation officials called it “an extremely rare accident.” Three passengers suffered minor injuries in the evacuation.

A preliminary report issued Thursday by the National Transportation Safety Board said controllers told the Eastern pilots that the instrument landing system’s glide-slope indicator, which helps determine the landing angle, may have been malfunctioning on the night of Dec. 27.

That alarm later proved to be false. However, investigators wrote, “The captain stated that since he had been advised the glide-slope indicator may not be reliable, he was conducting the approach primarily on visual cues.”

One type of visual cue is the series of lights in front of the runway known as VASI, or “visual approach slope indicator.” While pilots are not required to use the lights, they can help when a visual landing is made, officials said.

The report said Runway 16, where the Eastern jet was making its landing that night, is the only one at Pensacola Regional that lacks a VASI system.

Henry Lawson, the Federal Aviation Administration’s chief of air traffic control in Pensacola, said the VASI system is not used on Runway 16 because that runway is equipped with the more sophisticated instrument landing system, or ILS.

The report did not say whether the jetliner’s approach caused the hard landing.