W7
only Qantas was listed by AERU as the proponent of the change,
My understanding is that was simply a matter of resources. A "proponent" was necessary, the internationals weren't in a collective really suitable for it,
VB & Jetstar are run lean, and QF did have the resources and were prepared to put their hand up.
So what Qantas said was that modern jets listed above that were designed to be able to fly the ICAO SARPS glideslope can't meet it, but only on the Arbey approach to Melbourne?
No, not exclusive to the Arbey approach, but any other scenario where a TD point is sufficiently close to CTR & CTA boundaries that the 2.82° gradient results in clipping steps. I don't know of any other scenario like it offhand. The approach to ML from the east west & south appear OK because the distance from the RWYs to the CTR/CTA edges is greater.
I'll leave the technical stuff to the airspace designers
