For many people, flying cars still belong firmly to the realm of science fiction. Aerospace company Joby Aviation (JOBY 0.84%) is trying to make them feel more like an Uber (NYSE: UBER).

The company's electric vertical takeoff and landing (eVTOL) aircraft are designed to fly over traffic at speeds up to 200 miles per hour. It's an idea that could change how we get around cities, but it's not yet a reality.

Down almost 30% from recent highs, is Joby Aviation an obvious buy right now?

A speculative buy, but with an asterisk

The bull case for Joby is pretty easy to sketch.

It's ahead of rivals like Archer Aviation (ACHR -0.78%) in the FAA certification process.

It's locked in a deal with Delta Airlines to shuttle its passengers to certain airports, and it also got a huge buy of confidence from Toyota, which invested $500 million to support its certification and commercial production.

And it had a magical "Wright Brothers" moment this summer after piloting the first electric air taxi flight between two public airports in California.

Two Joby Aviation eVTOLs on a runway.

Joby eVTOLs. Image source: Joby Aviation.

The company also had a strong balance sheet with about $991 million in cash and investments at the end of June. And it recently got a major push from the White House, whose executive order to accelerate deployment of advanced air mobility could help it secure much-needed approval to fly eVTOLs commercially.

But therein lies the bear case: Joby is pre-revenue, and it doesn't have certification to fly paying passengers. Expenses for R&D won't be cheap, and without operational revenue, the company's cash burn can become a serious impediment to its expansion. With a second-quarter net loss of about $325 million and a market valuation of $12.4 billion (at the time of writing), the company already comes with high expectations.

As such, consider Joby Aviation a speculative play for the transportation industry. It's not an obvious buy for everyone. But for those who can stomach the risk, it's a compelling stock to consider.