I have been flying the 737NG for a long time and have also been traveling to and from work every week in the cabin for a long time. Recently while sitting at a window seat during a night time flight home , I noticed that the strobe and beacon lights suddenly change out of their normal sequence or stop altogether for maybe 30 seconds. I have seen this on numerous aircraft with many different crews so it can't be a tech or personnel issue.
I have checked FCOM's and maintenance manuals but can't find an answer. Can anybody shed light as to what is the reason for this? Our aircraft vary in age from brand new to around 15 years old.
Also I know that I have too much time on my hands to have noticed this
