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  • James01
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James01 created the topic: PAL

Hi All, this is my first post. I'm currently studying for my IRX and I'm a little confused. This question is relating to non RPT. If the Alternate aerodrome lighting is PAL operated an alternate is required unless a responsible person is available to manually switch on the runway lighting. AIP ENR 1.1 para and ATC AU-303 3.4.3.

Then there is a "Special Deal for the Alternate comment"
You do not need to have standby power or a person in attendance if the alternate you choose has PAL so long as
1. Not RPT and not above 3500kg MTOW
2. you have 2 VHF radios,
3. or 1 VHF and 1 HF and 10min holding fuel.
AIP ENR 1.1 para ATC AU-303 3.44 to 3.4.7

My question is, What is 2 VHF radios going to do if the PAL is not working? you have no standby and no person to put out portable lighting???

Any clarification will be helpful?

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S70BlackHawk replied the topic: PAL

Hi James,
The PAL question can be confusing at first especially if you haven't been exposed to NVFR or IFR at night. But easy once you understand a simple concept of what you need, and who provides it, becomes more apparent.
Sorry for the lengthy reply, but should explain in detail the "why" and therefore remember it better I hope.

You have many types of airports you can fly to at night. From Brisbane International where the lights are always on and have a backup power source with ATC active always, to Proserpine Airport where there is no tower and is serviced by PAL with backup power to an outback runway with only portable lighting.
If you think of it in a way that says, "what lighting do I have (fixed or portable), what are the chances of it failing (standby power or not) and who is going to switch it on (ATC, Pilot with PAL or responsible person)?"
Well, you need the lights of the runway to be on and not to fail! Especially during final approach.
AIP 10.7.4 Runway Lighting Portable lighting - this is obvious because you need a responsible person to check and lay out the lights. You need an alternate if you don't have this person or the lights. Standby Power - So, any electric lighting (non-portable) with backup guarantees the lights will be on as far as the power source. If there is no standby power, you can't guarantee they'll stay on because of a power failure. So without the backup you automatically need an alternate or the responsible person with portable lighting again. This leads on to the next paragraph which talks about PAL. So even if you have electric lighting and a backup, if there is only you as the pilot to activate the lights then read the next paragraph. PAL - Now I need someone to switch them on. So if the lighting isn't PAL activated like Brisbane, ATC are there to switch them on or keep them on. They are your responsible person.
Without ATC, and the lights are PAL activated, then YOU switch them on with your radio. If you can't, then you need to divert to your alternate aerodrome OR have a responsible person on the ground that can go and press the button at the aerodrome to turn them on for you. This is because either your aircraft radio VHF box can't or the PAL box can't because the unit has failed.
This has happened to me, and I didn't have the responsible person on the ground. So I couldn't land there. It wasn't my destination though!
So, let's say you don't have a responsible person to switch the PAL on at your destination and you can't get the lights on with your radio, the only thing to do is divert to your alternate.There is no other way to switch PAL on. Alternate Aerodromes - PAL - So you've flown to your alternate aerodrome. It is PAL activated too. CASA says that basically the chances of you having two aerodromes with failed PAL is unlikely. So that is why you have the "Special Deal" as you put it.
Either the responsible person is on the ground at your alternate to switch the lights on, OR you can use:
a. Dual VHF (this means that if one of the radios can't switch on PAL, then try the other radio as both are unlikely to be failed); or
b. single VHF and HF and carry 30 mins holding. As it says, 30mins holding is to alert ground staff to come and switch on the PAL for you. HF is mentioned as these radios can be used to patch a phonecall to someone through Flightwatch.
So a and b are basically accepting the little to no risk that PAL at a second airport is going to fail.
Paras 5,6,7 are self explanatory.

One tip for young players is, make sure you understand ERSA INTRO -12 Para 23.4.
There is a difference in how long you key the mic for PAL with AFRU and without AFRU.
PAL without AFRU you can key the mic and say "let there be light" 1 SEC off "let there be light" 1 SEC off "let there be light."
PAL with AFRU you key it quickly with 1 SEC bursts.
Without AFRU you won't know the lights are on without being visual with the runway. AFRU will tell you that the lights have switched on and will also warn you about the "end of light cycle running."

Hope this helps!

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  • James01
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James01 replied the topic: PAL

Wow, thankyou for taking the time to explain in the detail that you have to help me here.

I now understand.


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ArrowHead replied the topic: PAL

Super helpful. Thank you.

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bobtait replied the topic: PAL

The AIP reference you have quoted has been amended since you found it. The current wording is as follows:

If it turns out that you will require an alternate due to aerodrome lighting, the alternate you choose can be PAL operated and need not have standby power or any person in attendance for your arrival providing:
1 A qualified person is 'on standby' for your arrival (not necessarily in attendance).
2 Your aircraft has at least 2 VHF radios,
3 One VHF radio and one HF radio plus 30 minutes holding fuel on arrival over the alternate aerodrome.
Part 91 MOS para 8.06 (4) & note.
AIP ENR 1.1 para to (ATC AU-303 3.4.4 to 3.4.7)

There are two contingencies that need to be allowed for. Firstly, your VHF radio might fail. If that happens, you would not be sure whether it's your radio or the PAL switching that's the problem. The two VHFs takes care of that.

If you have only one VHF and the PAL switch at the alternate is not working, you need HF as well so that you can call flight watch and ask for someone to be sent to manually turn on the lights. The 30 minutes holding takes care of that.

Of course it's possible that the power supply to both aerodromes might fail due to a lightning strike! In that case you've had a really bad day.

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