How Far Will Boeing's Stock Drop as Its Planes Are Grounded? Boarding1Now / iStock Editorial via Getty Images Boeing Co. (NYSE: BA) stock is down close to double digits on a decision by the Federal Aviation Administration (FAA) to ground 171 Boeing 737 Max 9 aircraft worldwide. The decision came after an Alaska Airlines plane lost part of its side while in flight. Images of the damage ended up on social media and spread like wildfire. While it is impossible to forecast how long these planes will be out of ...