[Cue wartime stories]
An airlaw question I got wrong in my exam was related to lighting of en-route obstacles.
The question was related to the colour of high intensity lights on tall buildings (I forget the actual wording).
The Trevor Thom / Pooley’s book just mentions “Obstructions which are over 500ft are lit.”
Air Navigation Order (ANO) – Article 219 is more specific and says:
Lighting of en-route obstacles
219 (1) The person in charge of an en-route obstacle must ensure that it is fitted with medium intensity steady red lights positioned as close as possible to the top of the obstacle and at intermediate levels spaced so far as practicable equally between the top lights and ground level with an interval of not more than 52 metres.
There is also the very nice
‘Visual Aids handbook’ from the CAA (CAP 437) which states:
“En-route obstacles are normally lit by steady red lights at night and, in exceptional circumstances, by high intensity flashing lights.” [no colour given]
I believe that the options were Steady white, flashing white, steady red, flashing red.
I answered steady red which was wrong, although having read all the above, you would be hard pressed to know it.
The answer sheet given by the CAA referred me to ICAO Annex 14, volume 1, chapter 6, para 6.3.33, which specifically talks about high intensity lights being flashing white. The steady red ones which we normally see are not high intensity. D'oh!
So... to know that, you would not only have to have read the books, nor just the ANO, nor the relevant guidelines issued by the CAA... but actually the underlying ICAO standard.
So, the moral of the story is that in practice, you may well get questions which are not in any of your books, and which may even not be in your national ANO.
Good luck!
B.