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Minima with actual QNH available
adrianchiasm created the topic: Minima with actual QNH available
I would like to enquire if there is an actual QNH such as an AWIS or ATIS and as saying if the DAP is shaded, you can reduce the Minima by 100ft.
However, what if the meterorological information provided in the ERSA with an AWIS PH number, there isn't any frequency allocated to it, can you still reduce the minima by 100ft? Of course as a pilot flying, practically you won't be able to use your mobile phone to dial for the AWIS. But in terms of the IREX exam, can you reduce the minima by 100ft?
For example in your textbook CIR revision question set eight question 9 pg 323, at Hay (YHAY) aerodrome, you may obtain AWIS thru the phone. But the circling minima for CAT A and B is 1000ft AMSL (695-2.4). You break out of cloud at 990 ft. Are you able to use the Circling minima at 900ft given the fact that you are able to obtain the AWIS through phone? There is also changes to the DAP chart for HAY with AWIS (Phone). If so, you are able to continue to the circling area for a left or right circuit RW 22 (Option b and c) will be right I supposed?
bobtait replied the topic: Minima with actual QNH available
That's a good question. There is no specific reference in the AIP regarding the use of a mobile phone but I have had discussions with CASA and they interpret it as follows.
If you are using it during flight planning to decide whether or not you require an alternate, then don't take the 100ft off since you can't be certain of mobile coverage and CASA/Air Services have no control over the mobile network and you are making a decision on the fuel to carry.
However when it comes to deciding the MDA after your arrival, you could take 100ft off if you did manage to get mobile coverage since you are not committed. If you cannot get mobile coverage, then you would have to use the published MDA for the approach. That sounds logical to me.
In other words, you could take 100ft off the MDA if you did get the actual QNH via mobile, but you might still need an alternate. You may notice that if ERSA says the the ATIS/AWIS is available via mobile only, there is no mention of ATIS/AWIS on the top of the approach chart.
In this case at the bottom left: Changes AWIS (Phone) is included. In the ERSA, AWIS phone number is also included
With reference to your text book CIR Revision 8 qn 9, assuming within your arrival there is mobile coverage and you obtain the actual QNH, therefore after taking off 100ft of the chart circling minima of 1000ft, you left with 900ft. You break out of cloud at 990 feet, so does that mean you can continue to the circling area with your option (b) and (c)? Both answers are correct? That means your answer (a) of conducting the missed approach won't be necessary anymore?
In the IREX exam with similar question like this, are we still going to use 100ft off the minima? Lets focus more on the theory side first. Cheers Bob