"Because," Elias smiled, "that indicates the —the runway is ending. And the last 300 meters are all red to show the runway end."

You scan options: 24%, 26%, 28%, 30%. You click 26%. The screen stays calm. You exhale.

"It's within the envelope," Elias confirmed, "but she’s going to be sensitive on the controls. We have a forward limit and an aft limit. We are safely in the middle, just closer to the rear. The aircraft will be slightly less stable but more fuel-efficient."