"When flying an instrument approach at night, in low visibility conditions - when should you put your landing light on? I've heard different opinions on this and would like to hear from one of your instructors. " - Dale D.
“While you may have been taught to turn your landing light on at night, no later than on final approach, it may not be the best procedure to follow during marginal or poor weather conditions.
In rain or marginal conditions such as fog, turning your landing light on may cause a glare to appear through your windshield. This glare may dazzle or surprise you and may tend to upset an otherwise good approach. Additionally, this glare may obscure the runway lighting which you need to keep in view in order to set up your touchdown.
(In these conditions) it’s better to hold off turning the landing light on until you’re on very short final, or even over the threshold of the runway when you’re sure you have your alignment as well as your altitude under control.”
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