Power supplied to an AC....
 

First of all, apologies for the bone question; I have searched on the internet for a definitive answer, but alas, no results just yet.

The quick question is - do your navigation lights have to be on when power is supplied to an aircraft?

I guess this is aimed at all those taking their ATPLs...not that there's many of those guys :ok:

Thanks in advance.

It's not a law for lights to be on and it mainly depends on who owns the aircraft (the operator's rules) and the rules for the airfield/airport your parking on/at...

I believe Mil rules often say that nav lights should be on to show that some form of power is "on".

I can't answer your question,
but I can say that the local police helicopters round here have some kind of stealth mode in which they turn off the navigation lights while hovering.

Whether they're on or off depends upon company procedures, but beware! On some aircraft they'll operate on the battery and if the power is turned off and you forget the lights they'll flatten the battery. I changed a lot of batteries in my junior days because of idiots who left the lights on. :(

In my rotary days it was 'norm' to have the Nav lights on (flash at night) when the a/c was 'manned' and the anti-coll on to show that rotors were being engaged.

EMA with a lot of airports Anti Cols on when running.

Appreciate all the replies.

Many thanks :ok:

Motley

My recollection also. Anti cols went on (to flash) when the engines were started. In those days, when ac were on the line, it was otherwise difficult to tell which ones had hot air coming out of the back, especially when wearing helmets due to the noise.

Civilian aircraft - B757, B767 etc.

Navigation lighting - Come on when A/C power applied.

An example of this is when the cabin lights are switched off, crew leaving through L1 door. Nav light still on until ground power is switched off.

Anti-Cols - Usually on when hydraulics pressurised before engine start. Most often left on post shutdown due to a missed switch.

Some light aircraft, typically Pipers dim the gear warning lights when the navigation lights are turned on to the extent that in daylight if you turn on the Nav lights, you can't observe the gear warning lights.

The answer is no. Nav lights are at pilots discretion, it's fine to turn them off during daylight hours. We tend to only switch ours off in bright sunshine, in cloudy conditions or at night they stay on. The beacon needs to be on when the a/c is capable of moving under its own power (switched on during the push / start checks, off during shutdown checks). The strobes go on when entering an active runway, off when exiting one and stay on in flight. Landing / taxi lights are to taste, but it's normal to have at least one white light on on the ground (for the subsequent board of enquiry) and landing lights on at all times below 10000ft.

HTH

LD

Can you have non flashing anti cols? :rolleyes:

On Boeings and Airbus in civilian guise anti collision lights are selected separately to any powered up status. On stand anti colls on means don't approach to ground crew.

Once powered up and ready to pushback - on go the anti colls. On entering a runway whether to take off or cross, on go the strobes.

THere again, what happens at Brize.....

SGC

Very good point about anti collision lights ... in the civilian ground service environment it is not uncommon for company procedures to rely on anti-col as means of determining if ground staff should approach an aircraft, or not.

In Tonka world nav lights would only be used by engineers during EGR or aircraft move at night. Crews would pop them on at some point during see off and then anti cols only once off the HAS site or pan, unless they wanted a chewing by the line controller on return!

Night carrier flying (aaaargh!) - nav lights on steady when checks complete and ready to taxi and be tensioned on the cat. On flashing when at full power and ready to go.

Mind you, that was nearly 50 years ago and I might have got it the wrong way round...

If you are studying for your ATPL exams, rather than canvas "military opinions" here I suggest you download CAP393 from the CAA website and read in particular Section 2 (Rules Of The Air Regulations 2007), Section 8, paras 46-55.

btw, There's no legal requirement for navigation lights by day at any time (nor any lights, day or night until an engine is running) ;)

Yep.
See post 2.