Boeing may have to shell out billions to airlines after regulators erased one of the 737 Max’s key selling points

• US and international airlines are preparing to return the Boeing 737 Max to service after a 20-month global grounding.
• Airlines must install several software and hardware fixes on the plane, but must also provide new, unprecedented pilot training.
• That training is expensive, and Boeing could end up footing the bill. 
• Here are the full details of how pilots will learn to avoid the conditions that led to two crashes killing 346 people.

Airlines around the world are gearing up to bring the Boeing 737 Max back into passenger service after the plane was grounded over safety concerns for 20 months, following two fatal crashes.

Along with revisions of various critical systems meant to avoid another disaster, one of the most important changes will be the training that pilots will undergo before getting behind the yoke.

Unlike when the plane was introduced, pilots will need to undergo several hours of flight training in full-motion simulators – a process that could end up costing Boeing billions.