Using LNAV for purposes of testing IPC Competency on an NDB approach

[Judd]

Hypothetical question. Take Melbourne Runway 16 NDB approach in an aircraft that has an FMS with the NDB approach in its data base. The aircraft does not have a GPS installed.

During the conduct of an IPC you are required to demonstrate competency at conducting the NDB approach.

The FMC NDB data base displays vertical guidance as well as lateral, allowing the pilot to theoretically choose to use LNAV/VNAV for the NDB approach. Plug in the automatic pilot and it is money for old rope as little flying skill is needed.

Because a computer generated glide path is available via VNAV, does this mean it becomes a 3D approach and not a 2D approach? Is that valid for the purpose of signing off the box for the NDB approach which is azimuth needle only?.

More to the principle of the flight test, is using LNAV or VNAV and LNAV together, a valid test of the pilot's competency to conduct an NDB approach?

Or should the approach for the purposes of an instrument rating test be a stand-alone exercise using the ADF needles only as azimuth guidance? Appreciate opinions preferably with documentary evidence. In other words, where can the correct answer be found in Part 61?

[Car RAMROD]

No it won't become a 3d approach.

Ndb can be azimuth or cdi, depending on your equipment. If they are usin the ndb to test azimuth on your ipc, then you definitely won't be able to couple it with lnav.

[alphacentauri]

It isn't a 3d approach

But if you use vnav, then it is classified as a 3d approach operation.

This is how ICAO are currently defining vnav operations on npa's

[alphacentauri]

Further...conduct of a 3d approach operation, is valid for recency of 3d approaches

[Judd]

If the intention was to shoot an 'old school NDB approach', then you're actually flying a 2D Azimuth approach. In that case, use of LNAV, VNAV and the CDI is prohibited...for the purposes of the test.


From the above comment, would it be reasonable to assume for the purposes of an IPC, any holding pattern procedure associated with the 2D (NDB) approach should not be on LNAV either?

[Capn Rex Havoc]

what is an NDB?