Each of the sentences has two meanings. In the first sentence, the ambiguity comes from the word “chicken” which refers either to chicken meat or the domestic bird, the animal, chicken. So the sentence can either mean “The chicken meat is too hot, so it cannot be eaten at the moment” or “The chicken feels so hot that it cannot start eating and needs to calm down first.”
In the second sentence, the ambiguity comes from the phrase “flying planes”. It can be understood as “the plane that is flying” or to “fly planes”.