N721EC

The flight crew reported that after an instrument landing system approach, during the landing flare the airplane encountered a strong wind gust and a go-around was initiated. During the go-around, the left tip tank struck the runway causing substantial damage to the left wing. The flight crew diverted to another airport where the weather conditions were more favorable, and upon landing, the damage to the left wing was discovered.About the time of the accident, the airport weather observation included wind from a heading of 300° at 15 knots, gusting to 20 knots. The calculated crosswind component was 18 knots. According to the airplane flight manual, the maximum demonstrated crosswind component was 24.7 knots.