IF a non IAP destination required an alternate if a TAF was unavailable- Clause B would say " For destinations with or without an IAP- where the aerodrome forecast is unavailable or provisional, an alternate must be planned"... However, it doesnt, it says
b) For aerodromes with an instrument approach procedure where an aerodrome forecast is unavailable or is “provisional”, the pilot in command must make provision for a suitable alternate.
If Clause B applied to a non insturment approach destination, then they need not write Clause C, however they do
C
)For aerodromes without an instrument approach procedure, the alternate minima is the lowest safe altitude for the final route segment plus 500FT and a visibility of 8KM (also refer ENR 1.10 Sub-section 1.4).
As i have stated earlier, Clause B is written as the IAL chart has an alternate minima which reqiures comparision to a TAF to determine alternate reqirements. A non- IAP destination has no such published alternate minima on a non-existant chart, thus Clause C comes into effect. ENR 1.10 supports Clause C in saying that a non-IAP destinations minimum is a GAP.
Consider this NOTAM found currently in the YBBN / MML FIR Notams
It is reffering to ENR 1.1's IFR alternate minima for weather section as an amendment to Clause B. My interpretation is that one may be planning to a destination and then requires an Alternate due to the existance of Clause B, as a result of
planning to do an IAP ( Note: Different to the situations we have been talking about earlier of a non- IAP destination) at their destination however the TAF is U/S, thus requring an alternate. However, COVID border restricitions potentially inhibits the ability of an aircraft to plan their desired alternate as it is across the nearby state border ( which is closed), therfore they have to plan to their secondary alternate ,which is within their state, but an extra 1.5 hours flight time. This causes excessive fuel load requirements and thus issues (ie. " E.G Insuffient Fuel".)
However, as a result of this NOTAM, one can disregard Clause B and effectivly apply clause C ENR 1.1 to a
positive IAP destination. Note, how the destination doesnt have a TAF ( since this NOTAM applies), however they still state to consider LSALT+5 and 8km visbility...... from the only forecast still available to them..... the GAF.