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Old 8th Nov 2020, 11:38
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scavenger
 
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Here we go again.

mmm345 is completely correct, just because an airport has no TAF does not mean an alternate is necessarily required.

AIP ENR 1.1 para 11.7.1.3
Where an aerodrame forecast is not available or is provisional, the pilot in command must make provision for a suitable alternate that has a firm forecast.
Means don't plan a particular airport as your alternate unless that airport has an aerodrome forecast that is not provisional. It says nothing about the destination aerodrome or the destination aerodrome's alternate requirements. It is in the 'general' sub-section' of a section titled 'alternate aerodromes'.

There is a list of airports that have TAFs normally issued in GEN 3.5 - these are the only airports that can be used as alternates, provided their TAF is not provisional.

Here is an excerpt from an email I sent about 4 years ago to Airservices to request an amendment, for the sake of not going through this on Pprune every few years (Para 59.1.3 is where the paragragh in question used to be)

I refer to AIR ENR paragraph 59.1.3, which concerns the requirement for the PIC to make provision for a suitable alternate.

This is often interpreted as meaning that:


A flight planning to an aerodrome that never has a TAF is required to provide for an alternate for the sole reason that the destination never has a TAF.

This is not what I believe to be correct, but a literal reading of 59.1.3, without reference to headings, indicates that interpretation is correct.
And here is their response (via an 'SME') with my bolding

AIP ENR 1.1, 59.2, 59.3 & 59.4 describe the circumstances (weather, navaids and lights) by which an alternate may be required. None of these require an alternate solely on the basis of the availability or otherwise of a TAF.

AIP ENR 1.1, 59.1.3 is intended to be read, as it is contained in Section 59 – Alternate Aerodromes, as the means by which an alternate is disqualified if the TAF is not available or issued as ‘provisional’.

It is not intended to be read as requiring all non-TAF aerodromes or landing sites to have an alternate if no TAF is available.
What they are saying is 11.7.1.3 means, if the aerodrome forecast at the the planned alternate is unavailable or is provisional, then a different alternate is required with a non-provisional (firm) TAF.

The rest follows simply:

No aid airport by day = alternate minima LSALT + 500 on last route segment and 8 KM vis, as determined from the GAF (which must be obtained for all flights) - navaid alternate requirements no longer apply by day (para 11.7.3.2 in the Radio Navigation Aids section), lighting and weather still apply with a different alternate minima
No aid airport by night (not greater than 5,700 KG) = alternate

No TAF airport (can never be an alternate), use the GAF/GPWT (which must be obtained) to determine the forecast weather and then use the Weather conditions section to determine if an alternate is required (see above if no aid as well, because if no IAL then no alternate minima on a plate, thus use LSALT + 500 etc), then lighting and navaids. But if an alternate is required, it must have a TAF that is not provisional.

Last edited by scavenger; 8th Nov 2020 at 11:53. Reason: typo, correction
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