nonerratic
/nɒnˈɛrətɪk/Definitions
1. adjective
not having or showing a tendency to become upset or irrational; calm and level-headed
“The experienced pilot remained nonerratic even in the face of the unexpected storm.”
2. adjective
not erratic in movement or action; steady and consistent
“The nonerratic pace of the athlete allowed her to complete the marathon with ease.”