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gillesdenice

Intercepting VOR radial when in HDG mode

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Hi,
With 737 NGX, i have no problem with that procedure.
But with the T7, no possibilities of intercepting a vor radial when in HDG mode.
Please, how can i do because i wanna train in VOR approaches. ?

Thanks a lot.

Gilles

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But with the T7, no possibilities of intercepting a vor radial when in HDG mode.

 

Correct.  There is no VOR/LOC mode.  You can still fly it in raw data and have the nav data displayed by selecting the approach on the DEP/ARR page.

 

Most of the airports the 777 is flying to utilize precision approaches, rendering the VOR/LOC function worthless.

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Don't forget when flying the radial in raw data to switch the heading mode from hdg to trk, this way the aircraft will correct for drift due to wind, you can also fly radials using lnav and the fmc but that's a write up.

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Thanks !

What do u mean by "flying in raw data" ?

Gilles

 

 

Not flying in VNAV/LNAV.

 

or more correctly, flying the VOR radial by looking at the deflection of the instrument which is measuring and displaying the radio beam information from the VOR navigation radio on the ground, not in reference to GPS, IRS or Flight Director based 'processed' information.

 

Flying a Raw Data ILS would be using the Glideslope and Localizer indicators to maintain course.

 

VOR raw flying is tuning the VOR radio frequency, dialing in the course, and looking at the indicator/needles on the VOR gauge (nav display) and reacting to the indicator deflecting left and right to adjust and maintain course.

 

The 777 Autopilot doesn't have the raw data on VOR capability. It can however follow a properly programmed LNAV track that has been set up to do the same thing (PBD waypoints like VOR270/12 (a track from the VOR, to a point 12nm directly west of the VOR) or proper approach selections from the Arrivals page of the FMS)

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Not flying in VNAV/LNAV.

 

or more correctly, flying the VOR radial by looking at the deflection of the instrument which is measuring and displaying the radio beam information from the VOR navigation radio on the ground, not in reference to GPS, IRS or Flight Director based 'processed' information.

 

Flying a Raw Data ILS would be using the Glideslope and Localizer indicators to maintain course.

 

VOR raw flying is tuning the VOR radio frequency, dialing in the course, and looking at the indicator/needles on the VOR gauge (nav display) and reacting to the indicator deflecting left and right to adjust and maintain course.

 

The 777 Autopilot doesn't have the raw data on VOR capability. It can however follow a properly programmed LNAV track that has been set up to do the same thing (PBD waypoints like VOR270/12 (a track from the VOR, to a point 12nm directly west of the VOR) or proper approach selections from the Arrivals page of the FMS)

Most of that is correct. To sum it up...raw data flyng means following needles...not following the flight director. The only thing that is a little misleading is this sentence:"The 777 Autopilot doesn't have the raw data on VOR capability".

Just like Kyle already wrote, you can follow a VOR needle and you can also still display the HSI with the course deviation indicator on the ND. Just not something you normally do on a 777. But for practicing....sure....its possible. But the AP and FD cant lock onto the VOR. You will have to keep the needle centered by flying the correct heading. Just like a Cessna...no AP, no FD just raw data.

 

Edit: or cheat a little bit (compated to a Cessna) and use the AP and have it fly Track Select rather then Heading select. Once established inbound on the VOR approach with track select it is real easy to keep the needle centered. But this way you are still practicing VOR intercepts and approaches.

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Thanks to you guys.

So when the 777 of Emirates (UAE77) land at Nice (LFMN), 90 % of the time with the VOR A 04L approach, it flies this approach almost manually !

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Not really, they can still do most part of that VOR appr using LNAV/VNAV until reaching circling MDA where they will disconnect the AP and switch off the Flight Directors, as long as the approach can be selected in the DEP/ARR page. From the MDA, it is basically a straight forward visual approach which will be fun.

 

If you are keen to do some manual flying with the PMDG777 you may try the visual circling approach into Haneda (RJTT) VOR rwy 16L/R approaches. Most of the japanese carriers do that with their 777.  A visual approach without any G/S assist requires good instrument scan and speed control (assuming manual thrust is used), and its most satisfying if you can master it. 

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Thanks to you guys.

So when the 777 of Emirates (UAE77) land at Nice (LFMN), 90 % of the time with the VOR A 04L approach, it flies this approach almost manually !

Sorry that I have to take the romantics out of here, but no :-(

 

You said you wanted to know how to practice old fashioned VOR approaches for practicing purposes. Nobody actually does that in real world though. Well, I mean, who knows there might be someone who actually does this for kicks, but you know what I mean. The 777 is an LNAV/VNAV airplane that uses GPS to determain its position. An ILS is the only approach that is still flown old fashioned stile. VOR approaches (and NDB for some airports) are both still in the FMC database because if ATC clears you for one you have to fly that. When you select that approach from the database, you will see how the magenta line gives you a visual display of the VOR approach. And then these Emirates guys follow this magenta line into LFMN with LNAV. So GPS is used to follow the magenta line with LNAV. Now officially this procedure is based on the VOR (you can see on your approach chart what equipment is required to folllow the approach down to the minimum descend altitude. and it will say VOR or VORDME). So there is actually still a requirement to cross check the VOR needles (make sure the VOR bearing pointer on the ND points to the inbound course) as you fly this with Lnav. And if the needles dont match with what Lnav is flying you would have to go around and find out what is wrong. I know it sounds silly to cross check Lnav/ GPS with ,in comparison, inaccurate VOR needles, but it is a fact that you have to!

 

The next step down from using LNAV is using Track Select, to follow the magenta VOR route and to keep those needles pointed where you need them. You would do this if Lnav failed for example.

Again, cross check with those VOR needles!

 

And the next step down from that would be to use heading select, to follow the magenta VOR route and to keep them needles where they need to be . This mode would be used for instance if the ADIRU can not calculate track anymore due to some failures. You now have to correct for wind drift yourself.

Again, cross check required.

 

And then finally comes your practice VOR approach.

If enough things have failed that there is no depiction of a map mode on the ND anymore then you have to revert to old school VOR flying.

Not having a MAP displayed on the ND is ofcource quite a bit more challenging as you cant easily see where you are going.

This requires true IFR skills!

Something you would hate to have to demonstrate into a mountain airport with pooring rain and wind gusts after a 10 hour flight through the night ;-)

Select VOR instead of MAP mode on the EFIS panel.

You now have a HSI displayed in full rose or expanded mode (selectable with the black button inside the left knob on the EFIS panel) and you need to fly a heading (or track if that still works) to keep the CDI (cource deflection indicator) centered.

 

Vertically you can follow your path with Vnav or VS or FPA.

Whatever you like using, but again Vnav would be the easiest (once you get comfortable with using Vnav that is....it takes a little getting used to but is a fantastic mode and perfectly simulated :-).

 

 

And then there are true GPS flown approaches.

Approaches that are based upon GPS, not VOR or NDB.

They are called RNAV GNSS or RNAV GPS or RNAV RNP approaches.

These are also selectable from the FMC database.

They are not called VOR 31 or VORDME 31 approach but RNAV 31 approach.

So there is a difference between them!

They are normally flown with LNAV and VNAV but again you could use Track select and VS just as well. The difference is that no cross checking of VOR needles is required to follow these approaches down to the published minimums. You are using GPS as the only source for position determination.

 

Hope this helps in the jungle of approaches out there :-)

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VOR approaches (and NDB for some airports) are both still in the FMC database because if ATC clears you for one you have to fly that.

 

Not to be disagreeable, but I don't want the simmers to take this the wrong way:

 

If ATC clears you for the approach, you should fly the approach, but you do not have to fly it.  The pilot can always reject the approach assignment, though that may mean holding until there is an available slot to accommodate the alternate approach.

 

The rest of that, though, is a gem of information for everyone.

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Not to be disagreeable, but I don't want the simmers to take this the wrong way:

 

If ATC clears you for the approach, you should fly the approach, but you do not have to fly it. The pilot can always reject the approach assignment, though that may mean holding until there is an available slot to accommodate the alternate approach.

 

The rest of that, though, is a gem of information for everyone.

That of course is correct....you dont have to anything :-)

 

But flying into NY JFK airport for example you seem to get VORDME22L 90% of the time. And they do have an ILS for that runway! I dont know why they seem to prefer the VOR over the ILS approach over there...maybe noise abatement as the VOR is off centered and maybe avoids a few houses....I dont know.

Anyway, fine by me, Lnav/Vnav here we go on the VOR approach. Now if the weather would be real bad or if you need the ILS for technical reasons, sure you would request the ILS.

Edit: you could even request the ILS just for practicing purposes, although JFK is not realy the kind of airport you go to, to practice things. I remember back in 2000 they already had a 100$ landing fee for Cessna type aircraft just to keep you away :-)

 

Thanks for the compliment Kyle :-)

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But flying into NY JFK airport for example you seem to get VORDME22L 90% of the time. And they do have an ILS for that runway! I dont know why they seem to prefer the VOR over the ILS approach over there...maybe noise abatement as the VOR is off centered and maybe avoids a few houses....I dont know.

 

They do it that way to give LGA a little more room.  If they're landing 22 at LGA, departing 31, they bring people around to the east side of LGA for the approach, which would encroach on JFK's 22 ILSs.  If they're landing 22, departing 13, they bring them to the west of the city (up the river, really), and the 13 departures could potentially cause conflict with the JFK 22 approaches.  Since LGA doesn't have an alternate/offset like JFK does, LGA goes with the ILS (or GPS overlay), and JFK uses the offset VOR until the weather gets low enough forcing them to timeshare the airspace.

 

More than you wanted to know, right?  Haha.  Sorry.  Investigating the CF that is NY was my old job...

 

 

 


Thanks for the compliment Kyle :-)

 

Welcome Rob.

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More than you wanted to know, right? Haha. Sorry. Investigating the CF that is NY was my old job...

 

No not at all, great info actually, thx, really!

 

Gosh I am going to be a wise guy on my next JFK if this subject comes up again (it does very often!) hehe ;-)

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Thanks to you guys.

So when the 777 of Emirates (UAE77) land at Nice (LFMN), 90 % of the time with the VOR A 04L approach, it flies this approach almost manually !

At Nice the modern jet use GNSS/RNAV 04L wich is exactly the same approach to not fly cap antibe

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Gosh I am going to be a wise guy on my next JFK if this subject comes up again (it does very often!) hehe ;-)

 

If you want a visual representation on how the airports all interact, there's a flash animation that the Command Center (where I did a lot of my N90 learning/studying) put together to show it:

http://tfmlearning.fly.faa.gov/NY_Airspace/NY_Airspace_Pkg/NY_Airspace.swf

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