Sending a spacecraft to Mars is no easy feat, but landing it on the Red Planet without making a crater is equally challenging. The European Space Agency knows that all too well, and a recent parachute test has raised serious questions about whether the ExoMars 2020 mission will remain on schedule.

A previous test in late May showed promise but was ultimately deemed a failure due to damage sustained by the two large parachutes that will be doing the majority of the work. This latest test included an updated design of the parachute arrangement but the problem reared its head once again.

The ExoMars 2020 lander is equipped with a complex parachute system that deploys in sequence to slow the spacecraft down and provide a soft landing once it reaches the Martian surface. A pair of large parachutes are pulled using smaller pilot chutes, one after the other, for a total of four parachutes deploying in sequence.

The May test went largely to plan, with all four chutes deploying in their desired sequence, but both main chutes sustained damage along the way. The same was true during the new round of testing, but ESA notes that it appears that the damage occurred prior to the larger chute fully inflating.

“It is disappointing that the precautionary design adaptations introduced following the anomalies of the last test have not helped us to pass the second test successfully, but as always we remain focused and are working to understand and correct the flaw in order to launch next year,” ESA’s Francois Spoto said in a statement. “We are committed to flying a system that will safely deliver our payload to the surface of Mars in order to conduct its unique science mission.”

The ExoMars 2020 team will now go back to the drawing board and attempt to design a solution to the problem. The lander and rover riding along with it are rugged machines, but a crash landing would obviously bring an abrupt halt to everything ESA has planned for the mission.

With the mission scheduled for a launch in late July or early August of 2020, ESA will need a bit of good luck to ensure it makes the date will a fully functional and well-tested parachute system.