FPO, I tried copying it but for it doesn't work here but if someone can copy paste that table I'd appreciate it.
This is significant to the crew in the respect that the crew has no idea where the center point of an RF leg is, unlike a DME ARC.
and how am I supposed to know that with DME being U/S? That's the whole point here. It might be depicted on the chart but if it's U/S there's no way to confirm it with raw data but as long as GPS is primary, accuracy based on a/c FMS calculation algorithm, is sufficient. DME ARC as RF is flown outta DB. The coding might be different but from operational point of view there's no difference whether I'm flying a RF leg or DME ARC without DME indication.
Another significant difference between RNP AR and all other forms of RNAV procedures is that, in accordance with the table FPO posted, an RNP AR IAP does not have to taper down as it progresses towards the runway. Segment widths can decrease, then increase, then decrease, except no segment can be of a lesser RNP value than the final segment, and the final segment cannot vary in width in a given IAP. Also, there is no secondary area obstacle protection, unlike all other instrument procedures.
That's all covered by the operational approval. I don't need to immerse into technicalities as I like to KISS. Keep it simple and short. Approval is enough grounds to make a decision.
