Exceeding 10,000 ft. is orthogonal to needing anti-/de-ice systems. In fact, you're often less likely to need them at the higher altitudes because it is too co

Exceeding 10,000 ft. is orthogonal to needing anti-/de-ice systems. In fact, you're often less likely to need them at the higher altitudes because it is too cold for airframe icing to occur. Counterintuitively, if it is too cold, you no longer have icing problems.