dChan - Q Origins Project Archive

Long detailed article about Boeing problems titled REDLINE

The first sign of trouble appeared just after takeoff.

Inside the cockpit of PK-LQP, a brand-new Boeing 737 Max belonging to Lion Air, the stick shaker on the captain’s side began to vibrate. Stick shakers are designed to warn pilots of an impending stall, which can cause a dangerous loss of control. They’re unmistakably loud for that reason.

But the airplane was flying normally, nowhere near a stall. The captain ignored it.

About 30 seconds later, he noticed an alert on his flight display — IAS DISAGREE — which meant that the flight computer had detected a sensor malfunction. This required a bit more attention.

A modern-day passenger airplane is less like a racecar and more like a temperamental printer: you spend more time monitoring and checking systems than you do actually driving the thing. So the captain passed control of the aircraft to the first officer and began the troubleshooting process from memory.

KEY FINDINGS

Mistakes began nearly a decade ago when Boeing was caught flat-footed after its archrival Airbus announced a new fuel-efficient plane that threatened the company’s core business. It rushed the competing 737 Max to market as quickly as possible.

In developing the Max, Boeing not only cut corners, but it touted them as selling points for airlines. Since the 737 Max was the same plane type as its predecessors, pilots would only need a 2.5-hour iPad training to fly its newest iteration.

MCAS is the new software system blamed for the deadly Lion Air and Ethiopian Airlines crashes. But its failure in both crashes was the result of Boeing and the Federal Aviation Administration’s reluctance to properly inform pilots of its existence or to regulate it for safety.

The FAA has admitted to being incompetent when regulating software, and, as a policy, it allows plane manufacturers to police themselves for safety. Nowhere in its amended type certification of the 737 Max is MCAS mentioned.

Even still, Boeing only recommends a 30-minute self-study course for pilots on MCAS, rather than additional simulator or classroom instruction.

Despite the two crashes, neither Boeing nor the FAA believes they’ve done anything wrong. A Boeing spokesperson said the company believes the system is still “a robust and effective way for the FAA to execute its oversight of safety.”

Like all commercial aircraft, the Boeing 737 Max has multiple levels of redundancy for its important systems. In the cockpit, there are three flight computers and digital instrument panels operating in parallel: two primary systems and one backup. Each system is fed by an independent set of sensors. In this case, the captain checked both instrument panels against the backup, and he found that the instruments on his side — the left side — were getting bad data. So with the turn of a dial, the captain switched the primary displays to only use data from the working sensors on the right side of the airplane. Easy.

All of this took under a minute, and everything appeared to be back to normal.

At 1,500 feet of altitude, the takeoff portion of the flight was officially complete, and the first officer began the initial climb. He adjusted the throttle, set the aircraft on its optimal climb slope, and retracted the flaps.

Except the airplane didn’t climb. It lurched downward, its nose pointed toward the ground.

The first officer reacted instinctively. He flicked a switch on his control column to counteract the dive. The airplane responded right away, pitching its nose back up. Five seconds later, it dove once again.

The first officer brought the airplane’s nose up a third time. It pitched back down.

https://www.theverge.com/2019/5/2/18518176/boeing-737-max-crash-problems-human-error-mcas-faa?utm_source=pocket-newtab