Formula 1 teams have been blindsided by a common issue in Barcelona pre-season testing as the sport ushers in a new era.
Drivers and teams have been racking up mileage in order to gain a better appreciation of how the new aerodynamic regulations that have seen a return to a ground-effect philosophy, and required an almost complete rethink to car design, will take effect.
Almost every car has been hit by a phenomenon known as 'porpoising', where the vehicle aggressively bounces on its suspension when travelling in a straight line.
The effect has not been seen in F1 since the sport left ground-effect behind, but could be the key to success or failure this year.
When air passes over a surface - either the front wing, leading floor-edge or both in this instance - to create downforce, the distance between the surface and the floor is reduced.
This increases the power of the ground effect and thus increase air pressure underneath the car.
The air pressure above the car remains the same, resulting in an increase in pressure difference between the underside of the car and topside and therefore produces even more downforce until the airflow stalls.
This causes the first surfaces to raise and restart the above process, repeating in a vicious circle until speed is abated.
Ferrari team principal Mattia Binotto explained: "Most of us underestimated the problem of on track, we are bouncing more than expected. We knew with the ground-floor situation, it is a learning process."
Asked if the cause was the same as the previous ground-effect era, he added: "The cars are quite different but it is related to the ground effect and how powerful it is.
"I think the regs of the car were slightly different but certainly, it is very similar.
"The frequency of the car bouncing is the natural frequency of the car itself and I think it is excited by the aero."
Alfa Romeo counterpart Fred Vasseur said: "We are all facing the same issue.
"To fix the problem is not the biggest issue but then to be efficient will be the key. How quickly the team will react will be the key for the first races.
"I am sure in three or four events, at the press conference, we won't speak about bouncing anymore."