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sinandgrin

Can You Do An Rnav Gps Approach With The Autoland?

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I have been struggling to find information in the FCOM, FCTM and in the forums that fully address the capabilities and limitation of the RNAV approach functions in the 777. I have no problem flying CAT III ILS Autoland approaches but I want to know if the autpilot will also fly an RNAV GPS approach and to what minimums, is it possible to fly an Autoland RNAV apporach, is this even possible or make sense?

 

Also I would like to make sure I understand the requirements, in terms of cockpit setup, to complete say an RNAV GPS apporach to LPV mins. For example the RNAV (GPS) Y RWY1C to LPV mins into KIAD.

 

Thanks for any help or references.

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Grumpy mode on - To Autoland you require an ILS signal. A major misunderstanding among many here is that ILS category is related to the aircraft's  autoland capability.   The aircraft does not care about CATI/II/III :) it will just Autoland.    

The category of the approach is determined by runway & approach lighting,hold short areas, and a bunch of other factors.  

 

To answer your question, no you cannot Autoland.

 

Take a look at the chart for the approach, LPV DA is 486ft (200)

 

 

 

Regards


Rob Prest

 

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Grumpy mode on - To Autoland you require an ILS signal. A major misunderstanding among many here is that ILS category is related to the aircraft's  autoland capability.   The aircraft does not care about CATI/II/III :) it will just Autoland.    

The category of the approach is determined by runway & approach lighting,hold short areas, and a bunch of other factors.  

 

To answer your question, no you cannot Autoland.

 

Take a look at the chart for the approach, it says for this RNAV approach the MDA is 900ft

LPV DA is 486ft (200)

 

 

 

Regards

 

Yes I was thinking that too since the LPV mins @ 486ft are still 200ft above the TDZE so it wouldn't make sense to be able to autoland.

 

With that cleared up and confirmed are there any unique FMA anounciations or other ques that I can look for to ensure that an RNAV apporach is correctly setup and that the plane is capable of flying to the lowest (LPV) mins? Aside from looking at the FMA for the VPATH Pitch mode is there anything else?

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I want to know if the autpilot will also fly an RNAV GPS approach and to what minimums, is it possible to fly an Autoland RNAV apporach, is this even possible or make sense?

 

The 777 can definitely fly RNAV (GPS) approaches.  You cannot currently autoland on a GPS approach.

 

 

 


Also I would like to make sure I understand the requirements, in terms of cockpit setup, to complete say an RNAV GPS apporach to LPV mins. For example the RNAV (GPS) Y RWY1C to LPV mins into KIAD.

 

Unfortunately, there's nothing you can do.  The 777 doesn't have GLS as it's simulated, so LPV isn't an option.  You can certainly fly the LNAV/VNAV mins, though.  No prep is necessary for the latter.  You could also technically fly the RNAV (RNP) approaches to 1R or 1C (not that either of them give you better mins - they're mostly there for the off-peak arrivals in slightly poor weather with transitions right off of the STARs.

 

 

 

Epic avatar pic, btw...


Kyle Rodgers

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Yes I was thinking that too since the LPV mins @ 486ft are still 200ft above the TDZE so it wouldn't make sense to be able to autoland.

 

With that cleared up and confirmed are there any unique FMA anounciations or other ques that I can look for to ensure that an RNAV apporach is correctly setup and that the plane is capable of flying to the lowest (LPV) mins? Aside from looking at the FMA for the VPATH Pitch mode is there anything else?

There are some things you can/should check before starting an Lnav Vanv approach, but I guess what exactly to check also depends on aircraft equipment and company SOPs.

 

For ultimate realism :-), these are my personal notes:

EO Non Precision straight in flown with LNAV and VNAV:

 

The minimum required equipment to accomplish a RNAV approach is:

 Two FMC (One is required if missed approach is not based on RNAV)

 One CDU

 One IRS

 Flight Plan Data on two ND´s

 One FD and one A/P on PF side

 Sensor receivers as required by approach (e.g. GPS for GPS/GNSS RNAV approaches, DME/DME update for DME/DME RNAV approaches, etc.)

 Current onboard navigation database including coded approach procedure

 Other items if restricted by approved MEL

 

So basically if any EICAS message appears in flight, then you have to check this list and make sure the failure does not effect Rnav capability.

 

For RNAV GNSS approaches check FMC for:

-RNP 0.3 entered on FMC position page

-Radio position updating disabled (disabled wIll have ON displayed in green, telling you disabled =on). This is probably just us though....we are not allowed to have radio pos updating enabled for Rnav approaches.

-Runway threshold coordinates (check approach plate runway coordinates to be the same as FmC database runway coordinates (as this is after all the point Lnav is taking you to)

 

For Vnav flown approaches, additionally check:

3 degrees glide path is indicated in the FMC LEGS page.


Rob Robson

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There are some things you can/should check before starting an Lnav Vanv approach, but I guess what exactly to check also depends on aircraft equipment and company SOPs.

 

For ultimate realism :-), these are my personal notes:

EO Non Precision straight in flown with LNAV and VNAV:

 

The minimum required equipment to accomplish a RNAV approach is:

 Two FMC (One is required if missed approach is not based on RNAV)

 One CDU

 One IRS

 Flight Plan Data on two ND´s

 One FD and one A/P on PF side

 Sensor receivers as required by approach (e.g. GPS for GPS/GNSS RNAV approaches, DME/DME update for DME/DME RNAV approaches, etc.)

 Current onboard navigation database including coded approach procedure

 Other items if restricted by approved MEL

 

So basically if any EICAS message appears in flight, then you have to check this list and make sure the failure does not effect Rnav capability.

 

For RNAV GNSS approaches check FMC for:

-RNP 0.3 entered on FMC position page

-Radio position updating disabled (disabled wIll have ON displayed in green, telling you disabled =on). This is probably just us though....we are not allowed to have radio pos updating enabled for Rnav approaches.

-Runway threshold coordinates (check approach plate runway coordinates to be the same as FmC database runway coordinates (as this is after all the point Lnav is taking you to)

 

For Vnav flown approaches, additionally check:

3 degrees glide path is indicated in the FMC LEGS page.

 

Thanks for the info, I'll use this as a rough guide when I do my RNAV approaches.

 

Unfortunately, there's nothing you can do. The 777 doesn't have GLS as it's simulated, so LPV isn't an option. You can certainly fly the LNAV/VNAV mins, though. No prep is necessary for the latter. You could also technically fly the RNAV (RNP) approaches to 1R or 1C (not that either of them give you better mins - they're mostly there for the off-peak arrivals in slightly poor weather with transitions right off of the STARs.

 

 

 

 

 

 

 

Epic avatar pic, btw...

 

 

Thanks for confirming that the 777 is not capable of the GLS (LPV) approaches.

 

...Danger Zone! :wink:

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