NDB/ILS/DME approach - what's the difference?
 

OK, call me stupid, but I'm confused. What's the difference between an NDB/ILS /DME approach and the ordinary bog-standard ILS/DME?
An example is the one into Sumburgh.

OK Stupid.

An NDB/DME/ILS approach uses the NDB/DME procedure to position onto the LLZ. An ILS/DME without an attached VOR or NDB procedure is usually positioned by radar or possibly on a DME arc from another facility.

:-}

I'm struggling to find a procedure designated NDB/ILS/DME in the UK. Can you give an example?

And you want me to call you "stupid? :)

It's entitled "NDB to ILS/DME" in the Aerads. However I can find no material difference between that and examples of "ILS/DME" with an NDB as the IAF.

Luton NDB/ILS/DME 26.

OK, I was asking for that. The difference seems to lie in the labelling - i.e. if Aerad
says NDB to ILS/DME it all makes sense after all! I'd only seen the Jepps plate.
Ta.

I'm not sure it does make sense, paraman!

The Sumburgh approach, labelled 'NDB to ILS/DME Rwy 27' uses the SBH NDB as an IAF and has a teardrop pattern to the localiser. It has optional DME arcs for 'direct arrivals'.

Cambridge has an 'ILS/DME Rwy 23' approach which uses the CAM NDB as an IAF and has a teardrop pattern to the localiser. It has optional DME arcs for 'direct arrivals'.

I can't detect a material difference in the nature of the procedures, yet one has a 'NDB to' in the title, and the other does not.

Australia's 'Departure & Approach Procedures' ie Oz equivalent to UK Aerad & USA NOAS approach charts: If a navigation aid is used in the title then it is a required aid for the approach.

Can't remember if that applies to the Oz edition of Jepps or to Aerads, NOAS or local Jepp publications.