Explain the difference between de-icing and anti-icing.

Explain the difference between de-icing and anti-icing.

• A. De-icing activates aircraft de-icing; anti-icing uses heat from engines to prevent ice.
• B. De-icing and anti-icing are the same; both remove ice.
• C. De-icing removes existing frozen contaminants; anti-icing prevents formation of ice for a period before takeoff.
• D. De-icing delays operations; anti-icing accelerates takeoff.

Answer: (C)

De-icing removes ice that’s already on the aircraft. It uses fluids and sometimes mechanical cleaning to melt and wash away ice from surfaces like the wings, tail, and fuselage so the airplane is clean for flight. Anti-icing is preventive. It’s applied before icing conditions to form a protective barrier that delays or prevents new ice from forming for a defined period (the holdover time). The surface can stay ice-free for takeoff if conditions don’t worsen and you stay within that window. If weather persists beyond the holdover time, reapplication may be needed. So the key idea: de-icing clears existing ice; anti-icing prevents ice from forming for a while before takeoff.

De-icing removes ice that’s already on the aircraft. It uses fluids and sometimes mechanical cleaning to melt and wash away ice from surfaces like the wings, tail, and fuselage so the airplane is clean for flight.

Anti-icing is preventive. It’s applied before icing conditions to form a protective barrier that delays or prevents new ice from forming for a defined period (the holdover time). The surface can stay ice-free for takeoff if conditions don’t worsen and you stay within that window. If weather persists beyond the holdover time, reapplication may be needed.

So the key idea: de-icing clears existing ice; anti-icing prevents ice from forming for a while before takeoff.