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triadic
8th Feb 2019, 03:54
I note in a draft for an entry in the May ERSA that the format for display of Lat and Long is changing from Sxx.yy.y Exxx yy.y to xxyyzzS xxxyyyyE. I understand that this change is to follow ICAO Annex 15 and was outlined in AIC H37/18 published in November.

Both formats are used within the industry, however I don't know if all GPS units accept the changed format? Further I don't recall any discussion or notification of the change or consultation taking place? Maybe the light was off when this came up!

Or is it another example of Airservices not consulting?

Capn Bloggs
8th Feb 2019, 12:19
Better get used to your 60 times table, Triadic! To make it a bit easier, don't worry about working out the decimal seconds... :}

cowl flaps
8th Feb 2019, 12:48
Degrees and decimals of Degrees is a much easier way. Go to 6 decimal places and that's it.

Mr Approach
9th Feb 2019, 04:58
Triadic - I don't think consultation is required when it comes to an ICAO standard - Australia must comply or file a difference with ICAO.
We do that a lot - but not in this case.

OZBUSDRIVER
11th Feb 2019, 21:11
For clarity of anyone reading this post. AIC H37/18-

2.2 The depiction of latitude and longitude will be degrees, minutes and, if required, seconds, followed by a cardinal point: e.g. 324620S 1382405E. If more precision is required, such as for ICAO data accuracy and resolution requirements, seconds will be followed by a decimal and tenths or hundredths of seconds: e.g. 324620.2S 1382405.1E or 324620.27S 1382405.15E.

2.3 Tenths of a minute will no longer be used to depict latitude and longitude

Actually, the more interesting part of the AIC is section4- Removal of Light Calculation
4.1 First and last light calculation methodology is currently published in AIP GEN 2.7. and will be removed as part of these changes. The calculation of first and last light may be obtained from NAIPS or the CASA website.

Is it just me? Or is the system getting dummed down? Granted, I am sure everyone gets the data off NAIPS when they are planning but, isn't it a good idea to have an access to a physical means of calculating the data without the use of electrons?

EDIT to add-Isn't it a far better idea to understand how the calculation is made if you can manually do it yourself? It gives you a sense of scale and magnitude when you look at the machine answer. Even if you never go near the calculation again after you sit the exam, you always know how it is calculated.

FGD135
12th Feb 2019, 04:37
Wholeheartedly agree with you, OZBUSDRIVER.

Capn Bloggs
12th Feb 2019, 05:06
Actually, the more interesting part of the AIC is section4- Removal of Light Calculation
That'd be as a result of the AsA user consultation process, no doubt.

CaptainMidnight
13th Feb 2019, 00:41
so why doesn't ATC adjust to pilot systems?
Ask ICAO - this change originated from them.

New AIC replaces the original one:

AIC H05/19 (http://www.airservicesaustralia.com/aip/current/sup/a19-h05.pdf)

Capn Bloggs
13th Feb 2019, 00:59
Let there be light! :ok:

You're quick, Midnight. Live on the AsA website, do we?? It's not on Ozrunways yet...

triadic
13th Feb 2019, 01:12
I would be interested to know when this consultation took place and what was it confirmed that all NAV systems and GPS units could accept this change

Ask ICAO - this change originated from them.

These changes are all 'recommended' and AU have the ability to declare a difference if considered appropriate.

CaptainMidnight
13th Feb 2019, 03:10
Live on the AsA website, do we??
:)

No, I just went looking for the AIC mentioned earlier and it was not listed, then saw the new one.

These changes are all 'recommended' and AU have the ability to declare a difference if considered appropriate.If the data providers and the rest of the World are changing - and I don't know if they are or not - we wouldn't want to be one to file a difference and be out of step with everyone else.

Despite being so with some other things ....