LNAV/VNAV approach and Missed approach altitude

[swissflyer2042 0]

In the past few months, I have a completed a number of approaches with the NGX, including ILS, RNAV, Visual, etc.

When flying an ILS approach, I reset the Altitude target to the Missed Approach Altitude once the LOC/GS have been captured.

Whenever I fly using the RNAV approach (ie using the LNAV/VNAV), I can't figure out when to reset the Missed approach altitude. The few times I tried, the descent stopped.

So did I reset the altitude too early, or is there another key press required ?

I watched a video on youtube on such an approach but it was in German and I didn't quite understand how the pilot did it. He was however able to set the Missed approach altitude on a RNAV approach.

 

Any help would be appreciated.

Thanks

Jean-Marc

[tcas_climb 45]

if you spin the knob fast enough while the plane is descending then it shouldn't go into ALT HLD. Make sure of course that you have already descended below the Missed approach altitude.

[rsvit 16]

You must be at least 300' below missed approach altitude and about 300' above MDA, then spin knob fast will work.

You can also try IAN (except for RNAV (RNP) approaches, where use of IAN is not authorized). In IAN you will have ILS interface, so you don't have to set MDA.

 

Instrument approach using VNAV: FCTM 5.51, 5.67, FCOM SP.4.6.

IAN capability: FCTM 5.59, FCOM 4.20.23.

You can also try instrument approach using V/S: FCOM SP.4.4, FCTM 5.64.

[wisefox7524 9]

I've heard that R/W ops, with a GPS/RNP approach, the altitude window on the MCP should be set to 0, and stay like that throughout the approach.

[KriVa 307]

Not at my outfit... We fly exactly like rsvit said. 300 ft below MAA => MCP window to MAA.

[sandpatch 9]

Jean-Marc, Can you post the video here? I have wondered the same thing and if you found a movie where he explains it I could translate.

 

Regards

Manfred

[Oliver Branaschky 2]

Jean-Marc, Can you post the video here? I have wondered the same thing and if you found a movie where he explains it I could translate.

 

Regards

Manfred

 

I think he's referring to the videos of Skysurfer007. A search on YouTube should do ;-)

 

 

Oliver Branaschky

[G-CIVA 62]

Best bet is to have a look at the QRH that came in the manual set with the product....all the different types of approach - both precision & non precision are clearly illustrated just as Mr Boeing intended....that & many many more Qs that you are too scared to ask or that have been answered a dozen times or more since release are answered in this document.

 

QRH Ch MAN.2.5 (pp 413)

 

No matter what you may have 'heard' out there in internet land or 'seen' on YT ...this is how the aircraft is operated IRL, with, granted, subtle differences dependant on type & operator.

 

Good Luck

[sandpatch 9]

Yep, makes sense. He mentions it several times. He only turn it up when he has the runway in sight and can fly manual. In the video ha says: "Turn it up and hope that it doesn't make VNAV jump out."

[swissflyer2042 0]

Thank you to all. I will try the suggested method as well as go back to the manual and read !

I have to admit that the 3000 pages of manuals is quite challenging for a non professional pilot.

 

In Rostyslav answer, I see a reference to IAN approach. I did see it in the manual and read that section too. However, whenever selecting an approach in the FMS, while seeing RNAV approaches, I have never seen an IAN approach. Is this due to the airport I have flown into ? How do you select an IAN approach then ?

Jean-Marc

[Spin737 102]

I've used both methods - 300' below the MA alt and dialing field elevation, and I've never had the real jet exit VNAV PATH.

[rsvit 16]

However, whenever selecting an approach in the FMS, while seeing RNAV approaches, I have never seen an IAN approach. Is this due to the airport I have flown into ? How do you select an IAN approach then ?

 

Because IAN is not an approach, it's a way of flying non-precision approach.

You select NDB, VOR etc. But it's highly recommended not to create your own waypoints between FAF and threshold.

Approaching final course press APP and fly like you fly ILS approach (with higher MDA).