EDITORIAL: What Boeing and Lion Air must answer for in deadly Indonesia crash

Airline passengers are demanding convincing proof from Boeing Co. that all its planes are safe.

Investigators are still piecing together what happened on Oct. 29 when a Lion Air 737 MAX 8 jet plunged nose-down into the Java Sea. Chicago-based Boeing insists its 737 MAX 8 is as safe as any other plane and blames pilot error for the crash.

But when a jet takes a nose-dive into an ocean and 189 people are killed, reassurances from the corporate flaks won’t suffice. Real questions demand full answers.

The single biggest question: Did flaws in the 737 MAX’s automated anti-stall technology — a prime feature of this latest model of the popular 737 — contribute to the crash?

Investigators say it’s still “too early” to tell. But it’s surely troubling that the new MCAS (Maneuvering Characteristics Augmentation System), designed to automatically lower the aircraft’s nose when sensors determine that a plane is ascending too quickly, apparently kicked in erroneously and sent the plane plunging.

Even as the desperate pilots tried repeatedly — 26 times — to pull it up.

Was Boeing aware of this potential malfunction? If so, when did the company become aware? What steps did Boeing take to warn every airline that used the new jet? Was sufficient pilot training provided in how to deactivate the MCAS when necessary?

Unions representing pilots for United, American and Southwest are sounding the alarm, claiming Boeing didn’t provide enough information, though Boeing denies this.

“The relevant function is described in the [flight crew operations manual, or FCOM], and we routinely engage customers about how to operate our airplanes safely,” an internal memo from Boeing President and CEO Dennis Muilenburg stated.

Meanwhile, there are questions for Lion Air, too.

Did Lion, the largest budget airline in Indonesia, properly maintain its planes? Did it warn pilots of the fatal flight that similar problems with the anti-stall technology had occurred with this plane before? Were all Lion Air pilots trained in how to override the MCAS?

Investigators suspect there were problems on all these fronts.

For our safety and their reputations, Boeing and Lion Air had better put it all out there.

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