SENSOR REPLACED DAY BEFORE CRASH OF LION AIR JET

JAKARTA, INDONESIA A crucial sensor was replaced on a Lion Air jet the day before it plunged into the Java Sea, and that sensor replacement may have exacerbated other problems with the plane, investigators said Wednesday.

That sensor, known as the “angle of attack” sensor, keeps track of the angle of the aircraft nose to help prevent the plane from stalling and diving. The Oct. 29 crash killed all 189 people on board.

The airspeed indicator malfunctioned on its last four flights, and that was related to the sensor issue, said Soerjanto Tjahjono, chairman of Indonesia’s National Transportation Safety Committee.

Lion Air’s first two attempts to address the airspeed indicator problem didn’t work, and for the plane’s second-to-last flight on Oct. 28, the angle of attack sensors were replaced, Tjahjono said.

On the Oct. 28 flight, the pilot’s and copilot’s sensors disagreed. The two-monthold plane went into a sudden dive minutes after takeoff, which the pilots were able to recover from. They decided to fly on to Jakarta at a lower-than-normal altitude.

The next day, the plane hit the water at very high speed just 13 minutes after takeoff.