BaroVNAVs are coming...

[Capn Bloggs]

I thought they were dead, but AIC 28/16 says they coming.

If the example of Horsham is anything to go by, a 190ft reduction to the minima (to circa 300ft AGL) is great. As Darth Vader would say: "Impressive".

[Mr.Buzzy]

I can only imagine the "required equipment" and "qualification/recency/conduct" thread on pprune.

Bbbzbzbzbzbzbzbzbzbzzzzzzzzz

[The name is Porter]

What happens at Horsham stays at Horsham

[Jenna Talia]

From an FAA fact sheet: LNAV/VNAV utilizes approved vertical guidance offered by WAAS and approach certified baro- VNAV systems

It appears as if WAAS is a requirement and we don't get that fully here. I wonder how this will otherwise be achieved?

[Capn Bloggs]

For "and" read "or".

[27/09]

For BaroVNAV to work you need to know the local QNH. Unless you have that then BaroVNAV is useless, unlike SBAS (WAAS).

[Capn Bloggs]

Originally Posted by 27/09

For BaroVNAV to work you need to know the local QNH. Unless you have that then BaroVNAV is useless...

It's called an AWIS. We do have a few of those scattered around the countryside here in Australia.

[Capn Bloggs]

27/09, where would you get your local QNH from at this place?

http://www.aip.net.nz/pdf/NZHK_45.1_45.2.pdf

[Brakerider]

Approved MET observer on the ground via a company freq?

[27/09]

Capn Bloggs:t's called an AWIS. We do have a few of those scattered around the countryside here in Australia.

As we also do here in this side of the ditch, but not everywhere. Like NZHK for example.

Capn Bloggs:27/09, where would you get your local QNH from at this place?

http://www.aip.net.nz/pdf/NZHK_45.1_45.2.pdf

Unless you're RPT you cannot.

Brakerider: Approved MET observer on the ground via a company freq?

If you happen to have such a service available, all very well for a scheduled operator, no good for Itinerant or Private Ops.

[underfire]

It meets the 250HAT minimum, so no problems with even non-compensated baro

[Capn Bloggs]

Originally Posted by Underfire

so no problems with even non-compensated baro

Relevance?

[mic310]

Does anyone know if this will become a 3D approach or 2D?

[Capn Bloggs]

3D. The minima is a true DA (see para 1.2 of the AIC).

[wishiwasupthere]

At the risk of it being a silly question, do you get a 'glideslope' representation on your HSI with these baro-VNAV approaches?

[Jabawocky]

Bloggs, hard to get any MET data in a lot of places the days, well maybe not the big airports you fly to, but the others

[roundaboutway]

Hey Bloggs, what does "true DA" have to do with it being a 3D approach? Aren't NPA's that have advisory vertical guidance calculated and provided by onboard equipment, 3D approches? regardless of a DA or MDA?

[drunk_pilot]

At the risk of it being a silly question, do you get a 'glideslope' representation on your HSI with these baro-VNAV approaches?

Not a silly question. If the aircraft is Baro VNAV capable (PBN S2), then it will have a glide path indication of sorts.

In Collins Proline 21 aircraft, the initial descent to the start of the approach is flown on VNAV PATH, and when the approach mode is armed and the aircraft descends through the capture altitude of the approach, the vertical mode will change from VPTH to VGP (vertical glide path or similar, can't remember the name). The glide path will continue to be indicated on the PFD in the normal manner, such as an ILS. Once the approach altitude has been captured (VPTH becomes VGP), the altitude alerter may be set to the missed approach altitude without disconnecting the vertical mode, much the same as flying an ILS approach once the GS is captured. The consequence of this is that the autopilot will fly straight through the minima if not disconnected. Again, the same as an ILS approach.

[Capn Bloggs]

Originally Posted by roudaboutway

Aren't NPA's that have advisory vertical guidance calculated and provided by onboard equipment, 3D approches? regardless of a DA or MDA?

They may be considered to be 3D approaches and flown as such, but it's up to Bloggs (or his company) to ensure he doesn't go through the MDA while doing his pseudo 3D approach and missed approach.

A Baro VNAV ie APV has a proper/true/real DA published. No mucking around with adding 50ft to the charted MDA to give a Derived DA and all that bla bla bla.

[Agent86]

Hey Bloggs, have they improved the system lateral tracking of your GPS approaches?
Can't have you landing on the taxiway.
Also LNAV/VNAV either need temp compensation capability or a temp limit. In Aus, the temp limit is not very "limiting" so would be the easiest option (and the only option for some systems). The problem with ISA+ temps is the Vnav invariably brings you in high on profile, necessitating a destabilising dip once visual.
ISA - temps bring you in low, hence the need for temp compensation to keep away from the hard bits beneath you.

I guess if the airport doesn't have an AWIS, it won't be getting an LNAV/VNAV approach.