The 737 MAX has been the big story for Boeing (BA -0.98%) for the past several years, first focusing on its potential to become the centerpiece of airline fleets, and then its design problems following two fatal crashes in late 2018 and early 2019. The COVID-19 pandemic only exacerbated this headache, by disrupting airlines' demand for new passenger jets. That's why even with the rebound in sales that began in October, Boeing shares are still priced at less than half of their all-time peak reached in early 2019.

The bulk of this weakness, however, may be rooted in a bit of misunderstanding of what Boeing really is. While commercial aircraft are a key part of its business, they're hardly the only profit center the company operates.

The Boeing you don't know

Don't misread the message. Passenger jets are still Boeing's biggest business. And problems with this business can certainly drag the company into the red.

Yet Boeing's got plenty of other ways to drive profits.

Take a look at the graphic below, which shows all the different sources of sales feeding into the company's total top line for the final quarter of last year. While commercial aircraft are Boeing's single-biggest business, this segment made up less than half of total sales. Space and defense accounted for roughly one-third of its revenue, while services made up about one-fourth.

Boeing's Q4-2022 revenue mix was driven higher by huge growth in commercial airplane sales.

And yes, this is roughly what Boeing's business mix looked like prior to all the setbacks that began before the pandemic.

Simply put, the corporation is much more than just passenger jets. Half of its business comes from either defense and aerospace or from the maintenance of this aircraft and equipment after the sale is made.

Then there's the rest of the story: earnings.

It would be easy to presume Boeing's biggest revenue driver is also its biggest profit producer. And, broadly speaking, that is the case. However, the commercial aircraft segment is also this company's least consistent and most unreliable source of net income. While some of its recent losses are attributable to the pandemic-prompted upending of air travel and then the fallout from problems with the ballyhooed 737 MAX, this business's bottom line was a bit unpredictable even before those headaches took shape.

Boeing's commercial aircraft profits are on the mend, but its defense and services businesses were never rattled to begin with.

Data source: Boeing. Chart by author. Dollar figures are in billions.

This makes sense. All aircraft require maintenance regardless of when they're purchased. In a similar vein, the world's military air forces are typically funded by governments willing and able to borrow money regardless of the global economy's condition. The same can't be said of commercial airlines.

A lot to like here

There are two big takeaways for investors.

First, don't be so distracted by matters that solely impact the sale of new passenger jets that you forget Boeing operates other ventures. While commercial aircraft are its single-biggest business, there are plenty of sales and earnings taking shape on other, more consistent fronts.

The second, bigger takeaway is this: Although it has dished out plenty of ups and downs since 2016, Boeing is still a bigger-picture growth machine.

And that's apt to remain the case into the distant future. Last quarter's 94% year-over-year improvement in commercial airplane sales still doesn't come close to reclaiming the revenue trajectory in place prior to the wave of disruption that materialized back in 2019. That leaves a ton more growth upside ahead. 

Boeing's big commercial aircraft business is starting to show signs of recovering.

Data source: Boeing. Chart by author. Dollar figures are in billions.

Better still, in its most recent Commercial Market Outlook the passenger jet maker predicts the world will need 41,000 new commercial jet aircraft by 2041 to meet the ever-growing demand for air travel, which aircraft leasing outfit Avalon as well as the UN's International Civil Aviation Organization (ICAO) Council predict could reach 2019's pre-COVID levels by the middle of this year.

Let's connect the dots. Boeing can survive even when its commercial aircraft business is under pressure. It can outright thrive when its commercial aircraft business is humming (which isn't even happening in earnest yet). Holding onto it just requires a great deal of patience to let these slow-moving factors do their thing.