BA Boeing Co

By WSJ City 

Efforts to get Boeing's 737 MAX jetliners back in the air have been delayed in part by concerns about whether the average pilot has enough physical strength to turn a manual crank in extreme emergencies.The problem has been the focus of weeks of engineering analysis, simulator sessions and flight testing by the plane maker and American air-safety officials.

KEY FACTS

--- Turning the crank moves a horizontal panel on the tail, which can help change the angle of the plane's nose.

--- Under certain conditions, including at high speeds with the panel at a steep angle, it can take a lot of force to move.

--- Regulators worry female aviators -- who typically have less upper-body strength than male aviators -- may find it difficult to turn the crank.

--- To complicate things, the same emergency procedure applies to the generation of the jetliner that preceded the MAX.

--- These planes are the backbone of short- and medium-range fleets for many carriers.

Why This Matters

All of the 737 MAX's underlying safety questions have to be resolved before the FAA can put the grounded fleet back in the air, according to US and European aviation officials.

Neither Boeing nor regulators anticipate design or equipment changes to result from the review. But the issue has forced a reassessment of some safety assumptions for all 737 models.

A fuller story is available on WSJ.com

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(END) Dow Jones Newswires

June 19, 2019 08:23 ET (12:23 GMT)

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