What happened

Shares of Boeing (BA -2.87%) were losing altitude last month, as the 737 MAX crisis continued to expand. Boeing's CEO was forced to resign, and the company said it will suspend production the popular jet, which has remained grounded since a second crash in March. As a result. the aerospace and defense stock  fell 11% over the month.

So what

Boeing's problems picked up early in the month, as the company invited industry stakeholders to Seattle to help build up support for recertifying the 737 MAX. However, at the same time, news reports continued to come out showing how much control over the regulatory process the Federal Aviation Administration had given to Boeing.  Also that day, new FAA chief Steve Dickson made plans to testify before Congress about the MAX on Dec. 11, putting the company back in a potentially negative spotlight. 

An airplane wing over a beautiful mountain scene

Image source: Getty Images.

The stock lost 5.6% over the first four sessions of December on worries that approval of the MAX would continue to be delayed. The stock's worst day of the month then came on Dec. 16, with shares falling 4.3% as the company said it would suspend production of the 737 MAX planes, a reflection of the impact the plane's grounding has had. 

Later in the month, shares bounced back briefly after the company said CEO Dennis Muilenberg, who was seen as having mismanaged the crisis, would be stepping down. Chairman David Calhoun is set to become the next CEO on Jan. 13.

Now what

Calhoun will have a lot of work to do when he takes over later in the month. He must repair relationships with airlines, negotiate payments for planes being grounded, and find a way to gain the FAA's approval for the MAX so the company can get back to manufacturing and selling the planes.

After an initial dive in March following the second crash, Boeing's shares have been surprisingly stable throughout the MAX crisis. The company will report fourth-quarter earnings on Jan. 29, which will give investors an opportunity to hear directly form Calhoun as well as a look at the company's guidance for 2020, showing the expected impact of the MAX crisis for the year.

In other words, expect January to be another busy month for the stock.