(CNN) — A surprise company outing to an air base caused a 64-year-old French man so much stress that he flung himself from a fighter jet in midair, grabbing the ejector button in a panic and tumbling through the skies above France before landing in a field.

The man had been surprised by employees at his firm, who had organized a joyride in a Dassault Rafale B jet for him as a treat.

But they apparently didn't know their colleague as well as they thought. Once the man arrived at the Saint-Dizier air base in northeastern France in March 2019 and realized what his co-workers had arranged, he began to feel extremely stressed, according to a fairly remarkable aviation accident report by a French government agency.

The unnamed man had never expressed any desire to fly in a fighter jet and had no previous military aviation experience, investigators discovered.

And thanks to a watch he was wearing which could measure his heart rate, investigators noticed that "his heart was in full tachycardia" before the flight, with a recorded heart rate ranging from 136 to 142 beats per minute.

But the man went through with the ride, joining a three-plane training exercise as a passenger. The Rafale B is used by the French air force, and has a maximum speed of nearly 1,400 kilometers per hour (870 miles per hour).

An image from the report, which details the man's surprise ejection. Bureau of Enquiry and Analysis for Civil Aviation Safety

When the jet was 2,500 feet above ground and the pilot began to climb, the passenger panicked and reached for something to hold onto.

Unfortunately, that something was the ejector seat button -- and the 64-year-old flew from the fighter jet.

To make matters worse, he had not securely attached his helmet, which went flying in midair.

Fortunately, the man avoided seriously injury after parachuting to earth in a field near the German border.

Investigators concluded that the error was caused by an involuntary reflex, prompted by stress and the jet's sudden movement.

The pilot was not ejected and managed to land the plane safely, despite suffering some minor facial injuries during the ordeal.