A shining light is fading out (i. e. when flying into fog, dust or haze). What kind of illusion could the pilot get?

Question

Question ATPL - Airline Transport Pilot license - Human Performance and Limitations

QuizVDS · Accepted Answer

The source of light moves away from him

QuizVDS · Answer

The source of light stands still

QuizVDS · Answer

The source of light is approaching him with increasing speed

QuizVDS · Answer

The light source will make the pilot believe, that he is climbing

Id 182 - ATPL - A shining light is fading out (i. e. when flying into fog, dust or haze). What kind of illusion could the pilot get?