Some top executives at Joby Aviation (US:JOBY), which makes a particular type of aircraft known as electric vertical takeoff and landing (eVTOL), recently bought company shares after the firm faced significant challenges since its debut

The eVTOL uses an electric motor to take off, hover and land vertically, which is more convenient than airplanes and their expensive and congested infrastructure. Sound testing suggests the aircraft is significantly quieter than helicopters.

Management may be able to back up its lofty ambition to become the flying Uber (US:UBER), thanks to its partnership with Japan’s automotive giant Toyota (US:TM) to produce the vehicle, dubbed “the flying taxi.” And it’s also acquired tech startup Uber Elevate, an air taxi project the ride-sharing firm launched.

According to a 2014 report by the Centre for Economics and Business Research and INRIX, Inc., the researchers discovered that at the then-going rate, Americans will waste $2.8 trillion on traffic by 2030 if improvements are not implemented.

The company’s shares on a year-to-date basis through July 25 fell 29%. Investors have proved a bit wary of the company since its nontraditional use of a trendy Special Purpose Acquisition Corp, or “SPAC,” to go public. SPAC-based IPOs have drawn skepticism and scorn as they dilute investment, and they have significantly underperformed the bench mark S & P 500 index.

That bearishness hasn’t dampened insider buying. On July 21 of this year, Joby CEO and chief architect JoeBen Bevirt bought 35,000 shares of JOBY at a price of $5.53. A few months earlier, on May 27, Bevirt acquired 55,137 shares at $5.67.

To be fair, not all insiders followed the head executive’s lead, with some choosing to sell JOBY stock. Moreover, it’s risky to assume the motivations behind insider transactions. Nevertheless, many experts, including VerityData’s Ben Silverman, generally view insider buys as a net positive for internal sentiment, though actual results are never guaranteed.