RNAV Approaches

[downscc 1,327]

2 minutes ago, scandinavian13 said:

There is a big push for a number of reasons to use RNAV, and my bet is that it will eventually take over ILS as the most commonly assigned approach (or vis app aid) in the years to come.

Assuredly this will happen.  As an ex-maintenance officer with an area of responsibility that included radar, navaid and meterological maintenance I can appreciate how expensive it is to maintain and operate these systems.  Even if they don't break, there are still periodic inspections and flight checks that are required. Each of these activities have a significant "support tail," big organizations with lots of people some doing things and most pushing paper involved in bureaucratic management.  Ground based systems like NDBs are already gone and the ILS and VOR will follow.  I suspect the military will keep some tactical TACANs, so some bases will have fixed TACANs for training.

[skelsey 765]

5 minutes ago, downscc said:

Ground based systems like NDBs are already gone and the ILS and VOR will follow.

Absolutely.

Meanwhile, no doubt they'll still find a way to require IR students to demonstrate raw-data NDB holds! I gather over the in the States GPS and RNAV-based stuff is now finding its way more in to the IR syllabus, which makes a lot of sense...

[iwebber 207]

3 hours ago, Yoda967 said:

This has actually come up for me, too, since KSAN's RWY 27 has LOC or RNAV only. Kind of amazing to watch the BAW 747/777s operate in and out of KSAN's 9,000 foot runway. VNAV really doesn't work on this approach.

Really? Why's that?

[DavidP 1,408]

5 hours ago, kevinh said:

but looking back I guess it was because some of the out of the way places they had to fly to didn't have ILS

Like YMML runway 34:

http://www.airservicesaustralia.com/aip/pending/dap/MMLGN01-150.pdf

Although the LNAV/VNAV minimums have only just recently been introduced

[Yoda967 23]

6 hours ago, iwebber said:

Really? Why's that?

I should have clarified: "VNAV in the 747 doesn't work for this approach." It's entirely likely that I'm doing something wrong.

[downscc 1,327]

12 hours ago, Yoda967 said:

I should have clarified: "VNAV in the 747 doesn't work for this approach." It's entirely likely that I'm doing something wrong.

I have flown the BAW EGLL KSAN flight in P3D with G-CIVX and as I recall I flew the RNV Y 27 approach without problem. The only issue is that the TropicalSim AFCAD needed adjustment with ADE to accomodate the jumbo.  I've since replaced that with the new Orbx KSAN and need to take a break from other chores and fly another heavy into there.  I notice that BAW is now flying the B77W on that route.

[Budbud 227]

Hi,

53 minutes ago, downscc said:

without problem

I did a few RNAV approaches with the 744 and everything went well everytime. However, I'm used to disconnecting the autopilot latest when reaching the FAP so I usually fly the final approach and landing manually.

But I also kept the autopilot connected down to the MDA a couple of times when the weather was close to the minima and didn't see any erratic behaviour. 

[sbclark 55]

Hi,

Thanks for the help...................the bottom line is that the 747-400 lacks what the 737 NGX offers. As Budbud offered above, I just can't use this as a precision approach. So I just disconnect the autopilot and hand fly to touchdown. The airport I was flying into is Phoenix (KPHX) where RW 26 is ILS and  RW 25R is LPV/WAAS capable.

Bill Clark

[downscc 1,327]

3 hours ago, sbclark said:

I just can't use this as a precision approach. So I just disconnect the autopilot and hand fly to touchdown.

Bill, all approaches (except an ILS CAT III) are hand flown from a minimum descent height, decision height or missed approach point, including ILS and GLS precision approaches.