Thanks mate.....I have been spending too much time in the sun, and climbing coconuut trees !!! Thank god for Google (white mans magic )...Two weeks...has been really great...especially sitting right at the back and learning new words to take home with me like "SHEILAS" !!!

Hi guys

Some clarification needed for my cloudy head .... re PEC

Check AIP ENR 1.5 (5.3.1) and (5.3.3)

I understand that if the minima are shaded and you have the actual QNH from an approved source then these values can be reduced by 100 feet.
However, reading the above ENR's, it appears that if you use the TAF QNH then all is as on the charts ... however, if you use the Area QNH then add 50 feet.

My query is .... is PEC simply the application of the TAF QNH

It is now 3:08am and I got to be mad ...

Regards

David

It says that if you don't apply PEC, you must add 50 ft to all DAs. So PEC applies only to an ILS [precision approach], no other approach has a DA, they have MDAs. Also you will find that almost without exception, the box is not shaded for an ILS, so the option for subtraction of 100 ft with the actual QNH will not apply to an ILS.

Hi Bob
Yep .... the idea of PEC tied to DA (and hence ILS) is OK.
Can't find any reference to where/how PEC can be obtained (unless ENR 1.5 5.3.3 page 33 is connected). So where/how can one get a PEC to allow the value (for ILS) to remain?
In fact does ENR 1.5 5.3.3 indicate that if the Area QNH is being used then 50 feet MUST be added to ALL values in table.

If we look at say Canberra (or even Hobart) the minimas are shaded even for ILS ..... therefore if actual QNH obtained (and you'd expect that given info on DAP chart), then 100 feet can be taken from ALL ... including ILS DA). Then of course add 50 feet to DA (only) if no PEC applied .... where can PEC come from ...

PS: some elaboration on ENR 1.5 5.3.3 (page 33)

Regards
David

Yes, IF the box is shaded you can take 100 ft off, Canberra and Hobart are an exception, most ILSs do not have a shaded box. PEC to be applied will not be found any Airservices or CASA document because it is specific to each particular aircraft. It will be found in the Aircraft Operator's Handbook or the company operations manual for each individual aircraft.

See AIP ENR 1.5 para 1.18.2

That's what I've been looking for ....

Any idea under what circumstances would ENR 1.5 5.3.3 (page 33) apply

Regards
David

It means what it says. If a TAF is not available and the area QNH is used instead of the local QNH [either forecast or actual], you must add 50 ft onto any approach minima.

One would imagine that doesn't come up to often ... but the situation needs to be covered ... I think I've flogged this one to death ...

Thanks Bob

Here we go again ...

Hi guys

A couple of niggly ones that again should be simple … but my head is spinning, ….
It is true that you must determine the approach/arrival procedure for destination before you depart.
I notice that Melbourne has DIFFERENT minima tables depending upon approach/arrival.

PART 1
Consider the MELBOURNE Minima table (ILS-Y) ….. (no shading, no 100 foot reduction)

It has double asterisk alternate special minima of 700/2.5 (not available for LOC/DME).
Does this mean you can ONLY use these alternate minima IF you are planning to use the ILS (and of course you have 2 independent ILS).
Ie if we have 2 independent ILS .. can we use that alternate special minima in our planning whether an alternative is required for any other approach.

PART 2
Now look at Melbourne VOR 34
Has double asterisk alternate special minima of 700/2.5
Does this mean you can ONLY use this for this planned approach AND you have 2 independent ILS onboard?

It has to be easy ......

David

Hi David,

If you take a look at AIP ENR 1.5 6.2 (specifically 6.2.1) it says:

"Special alternate minima are available for specified approaches at some aerodromes for use by aircraft with dual ILS/-VOR approach capability; ie, with duplicate LOC, G/P, marker and VOR receivers..."

In other words, dual ILS receivers.

That means, to take advantage of special alternate minima, you need to have dual ILS fitted, whether you're planning for the VOR 34 or the ILS-Y approach. Without dual ILS you can't use the special alternate minima.

> I notice that Melbourne has DIFFERENT minima tables depending upon approach/arrival.
The special alternate minima are actually the same for all approaches where a special alternate minima is specified (ILS-X,-Y and -Z and VOR 34), namely 700/2.5. There is however a note on the ILS-Y chart that states the special alternate minima are not available for the LOC/DME approach which makes sense. You'll also notice explicit exclusions added to the other VOR approaches (VOR 09, 27): "SPECIAL ALT MNM NOT APPLICABLE"

Bottom line, if you are planning a flight to a destination and your decision on an alternate depends on being able to use the special alternate minima, then you must have dual ILS fitted and you must be planning to use (or expect to be given) an approach where the special alternate minima are applicable.

Cheers,

Rich