Pulsing 'vanity' lights ??

[Rod Sloan]

Hi All,

Was outside last night at dark time and watching a QF jet on departure from YSCB. I noticed the tail fin lights 'pulsing' ?

I dunno if the lights that shine back onto the tail are actually called 'vanity lights' but it seemed to be that it was these ones that were pulsing. Quite an unusual effect watching the roo light up/go dark/light up etc etc. Then they just shut off altogether and the jet went on its merry way.

Just curious as to why these lights would have been pulsing though ?

Cheers
R