Coupled Approach

[Captain Smiley]

Does an auto-pilot "Coupled Approach" only refer to an ILS with Loc and Glideslope or can a VOR approach be flown coupled as well.

[Erebus]

"Autocoupled" approach is for ILS only, with or without autoland.
VOR, NDB and other non-precision approaches can and may be flown with an autopilot engaged.

[Intruder]

Depending on the airplane and the airline OpSpecs, a coupled approach may be flown on any instrument (or visual) approach. The big differences are the specific autopilot modes used, the lowest altitude to which the approach may be flown, and whether or not it may be flown to touchdown (autoland).

I've never seen the term "autocoupled" before...

[Rainboe]

I think outside the US it is in common useage.
I've always taken autocoupled approaches to mean coupled only to a LOC, normally with GS, but not leading to an autoland.

*Erroneous statement removed!

[robtherower]

Rainboe : Its our SOP to fly VOR approaches in VOR/LOC and V/S mode... never had any problems.

rob

[Rainboe]

Yes you are right- I was in error there. I can't actually ever remember flying a VOR approach at all in 747 ops, but it is done!

[L G Cooper]

Generally speaking "coupled aproach" refers to whether the autopilot is providing control deflections as commanded by a navigation source. This nav source can be a couple of things: you can have a ground based navaid provide the guidance as in the case of an ILS or VOR/DME or you can have an onboard system such as the FMS for a GNSS/RNAV approach. The "middleman" here is the flight director. As an example, for an RNAV approach you'd select the FMS as your data/nav source which would schedule your flight director displayed as command bars (chicken lips) and pseudo glideslope on your EFIS. You can handfly the approach from there if needs be or you could engage the autopilot - "couple-up".

LGC:ok: