Definition
Describes an airplane, system, or component designed and certified to continue operating safely with a limited accumulation of ice on specified surfaces, rather than requiring all ice to be removed or prevented. An ice-tolerant design accepts that some ice will form and ensures that handling, performance, and system function remain within acceptable limits when it does.
Plain English
Built to keep working safely even when a small amount of ice has built up on it, instead of needing to be kept completely ice-free.
Context Anchor
Seen in discussions of airplane anti-icing and deicing equipment, especially when comparing systems that prevent ice with designs that can safely carry some ice for a limited time.
Derivation
‘Tolerant’ comes from the Latin tolerare, meaning ‘to bear’ or ‘to endure.’ An ice-tolerant part is one that can bear a certain amount of ice without failing, rather than one that has to avoid ice entirely.
Why Pilots Care
Determines whether an aircraft can continue operating in light to moderate icing without immediate diversion or de-icing action.
Intuition Check
Do not read ice tolerant as “ice-proof.” It means able to safely handle some approved amount of ice, not unlimited ice or severe icing.
Example Sentence 1
The propeller on this airplane is ice tolerant, so a small amount of ice on the blades will not immediately cause unsafe vibration or loss of thrust.
Example Sentence 2
Before entering known icing conditions, confirm the aircraft is rated ice tolerant for the expected severity.