Taihou can launch planes even when she is at orange hp.
Other than having high firepower and armor but low evasion, Taihou is currently the only CV able to launch planes at moderate damage (orange).
Seriously, what the others have mentioned.
I feel I should share a little tidbit I was clarified upon recently. Aircraft carriers do not lose all utility at medium damage.
While Taihou's advantage is great, speaking in terms of game mechanics, the phrase "can launch planes at medium damage" in the English wiki is highly misleading.
Well, it's based on history. Taihou is the new generation aircraft carrier by the Japanese, using much heavier armor to withstand more damage, although sadly she sunk with just 1 torpedo hit.
Anomalyzer It was because she was built with an armoured flight deck as opposed to the regular lacquered wood of the other carriers.