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CharlieLimaX-Ray
26th Aug 2010, 07:14
The usual training department scenario, the aircraft has a delayed departure and on your arrival at the destination the tower will be closed.

Due to low cloud, poor visibilty and prevailing wind you will have to carry out a coupled ILS approach as per compnay ops manual on arrival.

In ERSA a note under lighting states that with PAL activation, the lighting with only go to Stage 2 intensity.

Therefore does that mean the ILS visibilty minima will have to be increased to 1.5 km, or can you use the lower minima of 1.2km?

Lasiorhinus
26th Aug 2010, 16:10
Which airport is this based on?

The generic answer would be, if there is no High Intensity Approach Lighting, then you need 1.5km vis.
Does the PAL also activate the HIAL? In Canberra, for example, which has an ILS and a non-24 hour tower, the PAL does not activate the HIAL at all, therefore you'd need a minimum of 1.5km vis in order to land off the approach.

Dog One
26th Aug 2010, 23:19
Interesting question CLX

Looking at the YMLT plates as an example, they indicate that the HIRL,HIALS and T-VASI are available outside TWR hours. The level of the lighting was set about mid range from memory, okay on a rainy night,but bloody bright on a foggy night. We used the applicable DA as required. The charts appear not to specify the approach light level set, or any restrictions for night use.

It would appear CB is no different to LT, the HIRL, HIALS and T-VASIS for RW35 are available via the PAL when the tower is unmanned.

Tinstaafl
27th Aug 2010, 03:58
Have any Oz PAL installations been upgraded to allow pilot controlled intensity? It's common here in the US. I loved it the first I used it, compared to PAL. The number of clicks on the mic. determines brightness from a selection of pre-set levels

Mind you, even vanilla PAL is better than nothing. I would have loved to have PAL available in the UK.

LeadSled
27th Aug 2010, 14:57
Due to low cloud, poor visibilty (sic) and prevailing wind you will have to carry out a coupled ILS approach as per compnay (sic) ops manual on arrival.

CLX,
Why the requirement for a coupled approach? This implies Low Weather Minima procedures, with DH below 200' agl, which you probably don't mean ??

Or did some dumbo write this in a manual to feel good??

Having high intensity lighting available does not imply they have to be on max. brightness, and if it was at night, max. brightness can be a real problem on short final.

This is where the US system is great, but we seem to always go for second best here (a bit like the ADS-B proposals). Come to think of it, 1.2 km some places I fly would be regarded by the locals as almost visual approach viz.

Tootle pip!!

PLovett
27th Aug 2010, 22:59
Tinstaafl, I have been shown a variable intensity lighting setup controlled by the pilot but for the life of me I can't remember whether it was a PAL or AFRU. I seem to recall that it was controlled by the 4th depression of the transmit button. This was in Australia but again I cannot remember where.

Tinstaafl
28th Aug 2010, 01:22
There was only single intensity PAL in Oz when I lived there. Pilot Controlled Lighting (PCL) here in the US uses the number of clicks of the mic. to set intensity. Typically 3 clicks within 5 seconds for low intensity, 5 clicks for medium, 7 for high.

I really like it.

CharlieLimaX-Ray
3rd Sep 2010, 07:04
So no one got an answer then?

Lasiorhinus
3rd Sep 2010, 14:45
So no one got an answer then?

Which airport? Then we'll be able to tell you.

But if the HIAL comes on with the PAL, then you can use 1.2km. If the HIAL doesnt come on, then it's 1.5km.