Joby Aviation Falls. What a 12-Minute Flight Means for the Stock.

Joby Aviation makes electric takeoff and landing, or eVTOL, aircraft. (Courtesy Joby)

Joby Aviation stock soared early Friday, and then came back to earth, after the company hit an important milestone.

Shares of the electric takeoff and landing, or eVTOL, aircraft maker traded as high as $18.89 before giving up gains and falling to $16.63 a share, down 4.3% on Friday. The S&P 500 dropped 0.3% and the Dow Jones Industrial Average gained 0.1%.

eVOTLs are a key enabling technology for shorter-haul air-taxi services, with lower operating costs and less noise than conventional helicopters. Many eVTOLs, including Joby’s, are in development.

Joby’s stock moves came after the company announced on Friday it had completed the first piloted air-taxi flight between two airports—Marina and Monterey, in California.

The flight covered about 12 miles in 12 minutes.

“For years, our flight testing has validated our aircraft’s capabilities, and we’ve done this across a wide range of environmental conditions,” said Didier Papadopoulos, Joby’s president of aircraft original equipment manufacturing, in a news release. “As part of the natural progression of our flight test program, it was time to venture further, and there was no better place to visit first than our neighbors in Monterey.”

Joby recently purchased Blade Air Mobility’s passenger air-taxi business. Blade operates a network of helicopters, mainly around New York City. The company flew more than 50,000 passengers in 2024 from a network of 12 terminals, including locations at John F. Kennedy International Airport, Newark Liberty Airport, and Wall Street.

Joby plans to deploy its eVTOLs commercially in 2026. Friday’s news was another step down that path.

Starting points probably best explain the stock’s intraday volatility. Shares have been incredibly strong in recent months. Coming into Friday trading, Joby stock was up 114% so far this year and up 233% over the past 12 months. Investors have become very optimistic about the potential for air-taxi services.

Gains have left Joby stock trading for about 300 times estimated 2026 sales of about $51 million. Sales are expected to ramp up quickly, hitting $1 billion by 2029, but significant profits aren’t expected until the next decade.

Nine analysts cover Joby. Only one, or 11%, rates shares Buy, according to FactSet. The average Buy-rating ratio for stocks in the S&P 500 is about 55%. The average analyst price target for Joby stock is about $11 a share.

Write to Al Root at allen.root@dowjones.com