An exterior aircraft light unit includes a mounting structure, an LED arranged on the mounting structure, and an optical system, arranged on the mounting structure for creating an output light emission distribution of the exterior aircraft light unit. The optical system has, in a first cross-sectional plane extending through the LED, a first concave reflector and a second concave reflector, each of the first and second concave reflectors having a proximate end positioned adjacent to the mounting structure and a distal end positioned removed from the mounting structure, with the first and second concave reflectors being arranged on opposite sides of the LED in the first cross-sectional plane, and a refractive optical element arranged between the first and second concave reflectors in the first cross-sectional plane. The distal ends of both the first and second concave reflectors that curve towards each other and have back-tapered shapes.