Surefooted

The mules of Piedmont are exceeding strong and hardy. […] They are the only carriage that can be used in crossing the mountains, being very sure-footed: and it is observed that in choosing their steps, they always march upon the brink of the precipice.

For many years I didn't learn to walk, because I was carried everywhere—not by my parents, who had grown frail, but by the most sure-footed of the servants.

Testers reported the locomotive as very surefooted and said it did not lose traction.

Her performance was described as "stunning, surefooted, breathtaking."