It's time for me to issue a mea culpa. A couple of months ago, I predicted a banner year for Boeing's (BA 0.46%) defense and space (BDS) business, so long as just one thing happened first.

If you recall, the new Vulcan space rocket, built by the Boeing- Lockheed Martin (LMT 0.88%) joint venture called United Launch Alliance, or ULA, had launched more or less successfully twice already. Vulcan was in line to receive national security certification to begin regular launches, worth billions of dollars, for the U.S. Space Force, and ULA CEO Tory Bruno expected to receive certification "momentarily."

That was three months ago, though, and certification still hasn't happened.

Unless it happens soon, I'm afraid Boeing stock could be in for a rough 2025.

Promises, promises

To be fair, even as he adopted an optimistic tone, ULA's CEO cautioned that certification might not come as quickly as he hoped.

Technically, what Bruno predicted was that ULA would receive Vulcan certification "momentarily." At the same time, he confided that when it comes to rockets, space, and space regulatory agencies, "momentarily" can mean either "this month, next month, [or the] next few months." In any case, Bruno expressed no doubt that Vulcan would win certification eventually.

That said, after three months of waiting we're starting to stretch the definition of a "few months," and investors in aerospace stock Boeing may be getting nervous at this point.

Why? Basically, it's because the promise of imminent certification underlies a second promise that ULA will launch Vulcan 20 times this year, setting a new record for the most launches ULA has ever made in a single year, and generating probably well in excess of $2 billion in revenue for ULA. As it's a 50% shareholder of ULA, half that revenue and half of any profit earned on it would belong to Boeing.

Presumably, Wall Street analysts have already built this promise into their financial models and their expectation that Boeing will hit $85 billion in revenue this year, and return to profitability for the first time since 2018 (according to data from S&P Global Market Intelligence).

But with every month that passes without Vulcan's receiving Space Force certification, that promise gets harder to keep. Boeing's expected 2025 space revenue shrinks a bit more. And the hope that Boeing will turn profitable again gets pushed even farther down the road.

Not all bad news for Boeing

I won't sugarcoat this: Boeing's in a bad place right now. Wall Street analysts forecast Boeing will eke out a small net profit this year, despite burning nearly $4.9 billion in negative free cash flow. But last year's labor strike, and the raises Boeing promised its machinists to end the strike, have left the company unlikely to earn any profit in 2025, in my opinion.

If Vulcan fails to launch as often or as profitably as planned, that's going to complicate matters further. It would mean less revenue flowing from ULA to Boeing. And it could mean Boeing doesn't return to profitability until 2026.

Image source: Getty Images.

But it doesn't mean Boeing will be unprofitable forever.

Reading the tea leaves, Ars Technica predicts that after a long delay, Vulcan will finally win certification in early March, and as a result, ULA's plan to launch 20 missions in 2025 "clearly [...] won't happen." Assuming Ars is right, my hunch is that Boeing's plan to turn profitable in 2025 will be stopped in its tracks.

Still, while 2025 isn't working out as well as hoped, any rockets not launched this year will almost certainly be launched next year. And over the long term, ULA still anticipates ramping up to a launch cadence of about 30 rockets per year, evenly split between commercial missions for customers including Amazon.com (NASDAQ: AMZN), and government missions for Space Force, NASA, and others.

Is that a good enough reason to buy Boeing stock, though?

Is Boeing stock a buy?

At a $130 billion market capitalization, which rises to a $160 billion enterprise value with net debt factored in, I won't be interested in buying this aerospace stock until it's profitable and generating at least $10 billion in annual free cash flow. Most analysts don't see that happening before 2028 at the earliest.

For now, I fear Boeing stock is not a buy.