Aerospace may not seem like a great place for investors right now, given the virtual shutdown of most airline travel. But there are parts of the industry that will survive -- and even thrive -- in the long term. 

If we think beyond the COVID-19 pandemic, I think Virgin Galactic Holdings (NYSE:SPCE), Heico Corp (NYSE:HEI), and Lockheed Martin Corporation (NYSE:LMT) have what it takes to survive this economic slump and come out healthy on the other side. 

Two Virgin Galactic aircrafts flying above an airport

Image source: Virgin Galactic.

Upending air travel as we know it

One aerospace company whose revenue hasn't been affected by the COVID-19 pandemic is Virgin Galactic -- and that's only because it had very little revenue to begin with. In 2019, the company had just $3.8 million in revenue as it invested in building and testing its spacecraft. 

Virgin Galactic isn't being affected in the short term, and I don't think the company's long-term prospects have changed since COVID-19 began to spread. The company is still targeting commercial travel for multimillionaires and has received 7,957 reservations of interest as of Feb. 23, 2020. 

What's appealing about Virgin Galactic is that its goal is to disrupt travel as we know it. A two-hour flight from Los Angeles to Tokyo, or a one-hour flight from New York to London are both possible with the company's spacecraft flying at Mach 5. Right now, given their $250,000 price tags, those tickets are only affordable for the ultrawealthy, but if ticket prices become affordable enough for (mere) millionaires, the business could disrupt the $900 billion commercial aviation market.

And that's a disruptive business I want to be a part of for the long term. 

The slow and steady aviation play

Heico doesn't get the publicity of a growth stock like Virgin Galactic, but it's a critical supplier to the aviation industry and highly profitable for its investors. The company's flight support business makes replacement parts for aircraft, and its electronic technologies business make subcomponents and subsystems for aviation, defense, medical, and more. 

Through a series of acquisitions and operational improvements, the company has nearly quadrupled its revenue in the past decade and seen net income jump nearly 700%. 

HEI Revenue (TTM) Chart

HEI Revenue (TTM) data by YCharts.

Heico's management has a long history of generating strong returns for investors, and I think that will continue once the COVID-19 pandemic passes. 

The military aviation giant

Lockheed Martin is one of the biggest military contractors in the country, with $59.8 billion in revenue in 2019 and $6.2 billion in earnings. The company may see a negative impact from COVID-19, but military spending isn't likely to take a hit like commercial air travel will. 

You can see below that Lockheed Martin's revenue and earnings have jumped over the last five years as programs such as the F-35 and Patriot missile defense programs grow, and with a backlog of $144 billion, we should expect the company to be a steady performer in the long term. 

LMT Revenue (TTM) Chart

LMT Revenue (TTM) data by YCharts.

Investors in aerospace should love the consistency of the military business that Lockheed Martin has built, and that's why it's one of the top stocks in the industry. 

Air travel is down but not out

The aerospace industry is going through a rough patch at the moment given the downturn in commercial air travel that will likely last for a year or more. But Virgin Galactic, Heico, and Lockheed Martin all have secure businesses that should carry them through this economic downturn and deliver them safely on the other side. Those looking to invest in solid businesses that look set for the long term could do worse than these three names.