Australian Alternate Minima and Special Alternate Minima
 

Can somebody steer me in the right direction to find out what the definitions and operational practical use of Alternate and Special Alternate minima on some Australian approach charts.

Does it mean that if the wx at destination is below this minima then an alternate must be planned?
Or if planning for a possible alternate, does the alternate wx need to at or greater than the alternate mimima on the alternate approach chart?

Try this,

http://www.casa.gov.au/wcmswr/_asset.../vfr/vfrg2.pdf


....as a starting point

I think the question relates to IFR approach plates that link only references VFR stuff.

Doesn't look like Oz uses PANS OPS II for alternate minima.

On the east side of the Tasman it's quite simple, the same minima requirements for having an alternate apply for all airports.

If the cloud base is less than 1000 feet above MDA/DA and or (the greater of) vis less than 5000m or less than 1000m more than required viz for that approach then an alternate must be nominated.

The wx requirements for an airport to be suitable to be used as an alternate are listed separately.

Weather below the alternate minima requires you to plan an alternate (or carry holding fuel if the weather is fluctuating ie INTER or TEMPO). The special alternate minima can be used in certain circumstances if the aircraft is appropriately equipped. An aerodrome can not be planned as an alternate if it itself requires an alternate. Full details in the Jeppesen manual or AIP.

Go to here. Aeronautical Information Package (AIP) | Airservices

Click "I agree" then choose "AIP Book", then "Enroute" then go to page ENR 1.5-34 then look under 6. Alternate Weather Minima.

It seems that the Alternate Minima figure on the chart doubles as both the minima at which an alternate is required and also the wx requirements for that airport to be able to to be used as an alternate. Very Australian.

Australia AIP ENR 1.5 34 explains all.

Basically if the weather at your destination falls below the Alternate / Special Alternate minima published on the destination approach plate during your period of suitability then you must nominate an alternate.

Special Alternate minima are published at certain aerodromes for the use of aircraft with the DUAL ILS / VOR approach capability i.e. they have two ILS / VOR receivers installed and serviceable.

SLAM (Special Alternate Minima) is NOT available for use if:

Local Metar / Speci forcasting unavailable (as notified by NOTAM)

An aerodrome control service is not available (as notified by NOTAM)

There is a protracted unservicability of any VHF approach aid of more than 7 days


So if a SLAM is published and you don't have any of the above NOTAM'ed conditions and your aircraft has the capability then you can use the SLAM minima.:ok:

That's because the criteria for alternate minima isn't contained in PANS-OPS II (or I). The criteria for derivation of alternate minima comes from criteria in CASA MOS 173 covering procedure design.

For info, the alternate minima is derived by adding 500ft to the height above aerodrome on the appropriate circling minima, and adding 2km to the circling vis.

From my IFR flying days, if the wx at the destination was below, or forcast to be below, the alternate minima, then an alternate had to be planned for. The rules are still the same.

Alpha

What about flying an Australian registered aircraft overseas where no alternate minima is published on the plates?

Thank you for your inputs. Now it makes sense.
 

I'm now 100 % clear on pre flight planning principals for destination and alternate forecast weather conditions.
ENR 1.5.34 and all your inputs have assisted greatly.

Then you use whatever is published in their equivalent of the Australian AiP,
Eg. USA, FAR 91.169 c 1 (i) for other than helis, either specified on the plate, or for precision, 600' 2 SM, non-precision, 800' 2 SM.

ps. SLAM??? Where'd that come from?

And slight correction to The full Special Alt Min req. are;
The ILS is not a single stand alone instrument, it is a system. No such animal as an "ILS receiver".

SAM used to be entitled Special Low Alternate Minimum, hence SLAM.

What about flying an Australian registered aircraft overseas where no alternate minima is published on the plates?

Then you use whatever is published in their equivalent of the Australian AiP,
Eg. USA, FAR 91.169 c 1 (i) for other than helis, either specified on the plate, or for precision, 600' 2 SM, non-precision, 800' 2 SM.

That would be a lot of different countries AIP's to read through if operating privately?

I guess if it was an airline, the company would have an approved op's manual for the alternate minima's for different countries?

Canada
Pakistan
Saudi Arabia
That took all of four minutes to look up those references and create this post
You will find you have to generally always nominate an alternate for your plan to be accepted, even when conditions are clear.:ok:

Just wondering if there is an Inter or Tempo at your destination but the wx is above the Alt Minima during that 30/60 minute period, do you have to allow for holding fuel? If so, any reference? Thanks.

Thanks for your help, any idea what the AIP reference is for that?

When I was flying in Aus I could never figure why guys where trying to jam 30 or 60 minutes extra fuel on board for an Inter or tempo when there was an alternate above minimums less than 30 minutes away from the destination

mattyj, because holding for 30mins would be more suitable than flying 30mins away to a place that isn't your destination and then having to get to your destination making a 1hr round trip? Even holding for possibly 1hr would end up the same but without an extra take off and landing required?

Yeah but that's not going to happen on some tempo prob 40...it MIGHT but it probably won't

Plus if it's 60 then you're weighing up leaving bags or freight behind