NCYankee wrote:
On the final approach segment, when a GS is available, the DME is not used, so substitution is not an issue. DME is only used on a Localizer approach to define FAF, stepdowns, and MAP.
Are DMEs never used in the US for GS check fixes? In Europe, it is not usual to have an ILS without either an OM or a locator so a DME is used to check the GS.
Airborne_Again wrote:
Are DMEs never used in the US for GS check fixes? In Europe, it is not usual to have an ILS without either an OM or a locator so a DME is used to check the GS.
There are fewer and fewer OM on ILS, most have been decommissioned. On an ILS, the FAF is available as a waypoint, this is the fix that one would use to cross check with the GS altitude. Since it is a named fix, substitution is as easy as it gets. Step down fixes inside the FAF are not relevant for the full ILS with a GS and only apply to the localizer only option.
In the US, I don’t use ILS anyway, so it is a non issue. I only use RNAV (GPS) with LPV. They are much easier to fly with a WAAS GPS navigator.
Airborne_Again wrote:
it is not usual to have an ILS without either an OM or a locator
I mean not UNusual, of course!
Has there been any progress on this in EASAland? My aircraft lacks an ADF (the previous owner removed it) and I have little appetite for installing one.
Mark_B wrote:
Has there been any progress on this in EASAland? My aircraft lacks an ADF (the previous owner removed it) and I have little appetite for installing one.
No, there has been no change.
I dont think you can fly an IAP using GPS unless it is marked as a GPS approach on the plate under EASA.
i.e it is NDB/DME approach that is what you need to fly it.
The planned change, for what it’s worth, is that EASA has mandated that by 2024 all instrument runway ends must have an RNAV APV approach.
liftvectorup wrote:
I dont think you can fly an IAP using GPS unless it is marked as a GPS approach on the plate under EASA.
Of course you can, there is no doubt about it. However, with the current law in EASA land, you need to have operational equipment installed to receive the underlying navaids.
However, nobody in his right mind would fly an NDB approach using an ADF.
achimha wrote:
However, nobody in his right mind would fly an NDB approach using an ADF.
I think that this is putting it a bit strongly. Pilots of my generation had a whole career of flying timed NDB approaches (ie, not even a DME). Of course RNAV is better and easier, but NDB/ADF does basically work and, except in very unusual circumstances, gives perfectly acceptable results (Shoreham 02 at dusk, with coast, hills and night effect is one of the exceptions, but we still got there without dying 
)
So, yes, RNAV is better, but “nobody in his right mind” is over egging it.
Carlyle RNAV consultation published 3/1/2018. I don’t have a link, as document was received from a 3rd party.
