A mixer includes a fresh air tube defining a passage having an inlet receiving
conditioned air from an air conditioning pack. The fresh air tube includes an outlet
providing mixed air to a cabin of the aircraft. An outer tube at least partially
surrounds the fresh air tube and receives recirculated air from the cabin. Multiple
holes in the fresh air tube fluidly connect the outer tube to the fresh air tube.
The warm recirculation air surrounds the portion of the fresh air tube to heat
it preventing ice from forming. The warm recirculation air entering the fresh air
tube through the holes homogeneously mixes with the conditioned air from the pack
to provide a uniform mixture of air within the fresh air tube, which further ensures
the prevention of ice build up.
