How to fly a VOR approach on the 320?

Good evening,

 

I would like to fly an automatic VOR approach with the 320.

I just have a doubt on the FCU. What ALT should I enter? The MDA? I want the AP/FD to do the landing (and then take it in manual - of course). What altitude? And should I keep the HDG managed?

 

Thanks

depends! some airports are different. If you like, airnav.com has all the charts for the USA so you can see all the altitudes and whatnot you need. Program it into the FMC of the Airbus (I assume you meant the airbus a320)

Good evening,

 

I would like to fly an automatic VOR approach with the 320.

I just have a doubt on the FCU. What ALT should I enter? The MDA? I want the AP/FD to do the landing (and then take it in manual - of course). What altitude? And should I keep the HDG managed?

 

Thanks

 

A VOR approach provides no altitude guidance...you'll have to manage altitude and descent rate yourself.

Yes but what should I enter in my FCU? I am just talking in general, not for a special airport...the MDA? I want the plane to leave me on the MDA...

 

Like for an ILS, I can enter any altitude, If i press LOC and APPR, It will still take me to the ground (of course, if signals are there, around 3000ft)

A VOR approach provides no altitude guidance...you'll have to manage altitude and descent rate yourself.

 

Agreed...but If I push the ALT (1000ft) and HDG knob (and I enter the course + frequency), will I be able to be on the MDA if my MDA > 1000ft?

You mean the one like St Maarten?

You have to go by the chart, no? It tells you the altitudes and you managed it with manually. Let Pv confirm because he does it the real-pilot way -)

Hmmm...No,

 

The Airbus has each and every VOR approach stored in the FMS's database.

It's flown by GPS. So if I put my HDG to manage, it will automatically align my bus with RWY....

 

Ok, let's wait! ;)

But VORs are offsetted, it can never direct you to a rwy centerline. And desccend is controlled with VS knob until you disengage the autopilot. Just thinking outloud, I too want to learn this aspect. You might want to duplicate this question on Aerosoft Airbus forum too and see what they say.

Hmmm...No,

 

The Airbus has each and every VOR approach stored in the FMS's database.

It's flown by GPS. So if I put my HDG to manage, it will automatically align my bus with RWY....

 

Ok, let's wait! ;)

 

I think that's not correct.

 

The AUTOPILOT flies the VOR approach,

It follows the pre-programmed plan in the FMC,

 

It does not use the GPS to know where you are.

It uses your initial position, that was entered when the plane was still on the ground before departure. From that moment every movement of the aircraft is detected, by using the gyroscopes inside. That is how the aircraft "knows" where it is.

-- I'm not 100% sure if the aircraft also uses the GPS to know where it is. I do know that accidents/incidents happened (real world) because aircraft did not enter the correct Initial Reference Position in the FMC. --

-- And, I'm not 100% sure your FMC even has VOR approaches, but, I dont have the aircraft. You say it has. So be it. --

 

Anywho, the aircraft knows the path you have to fly, but you will have to manage the altitude. Keep an eye on where you are. When you are at the FAF (Final Approach Fix) you have to start the correct descent.

For example, if the FAF is 10-NM from the runway, at 3000-ft, you have to make sure you get there, and then start the correct descent.

 

That can be a 5% descent, descending continually at the same angle.

You would then set 5% (or 3.3 degrees) on the autopilot, but you have to then descend to Minimums Altitude, make sure you have the runway in sight (if you can't see the runway at minimums you are not allowed to go lower!!!)

And if/when you have the runway in sight, switch off (parts of) the autopilot, to do the landing manually. (If you do not switch off the autopilot, the plane just continues descending and crashes into the runway!)

Real aircraft, and some payware aircraft, has a switch to start a 5% (or 3.3degree) descent and follow that path. Airbus was the first to introduce that.

A 3.3 path from the FAF, SHOULD follow the same path a glideslope would be, IF you do it correctly. A glideslope goes down (up) at an angle of 3.3 degrees.

 

You could also do that 5% (3.3degree) descent manually all the way, while the autopilot only guides your heading.

 

You could also do a stepped descent, flying level for a while, then descending steeply while speed increases, then level off so speed drops again, untill you are at MDA (minimum descent altitude). Then maintain that untill you see the airport.

 

Whatever you do, you must always KNOW if you are on the glideslope. You can't just trust it that the autopilot is actually following that 3.3 degree angle!

What does a 3.3 degre angle mean for: "Distance to Airport" vs "altitude Above Ground Level (AGL)"

Distance -- altitude AGL

10 NM -- 3000 ft AGL

09 NM -- 2700 ft AGL

08 NM -- 2400 ft AGL

07 NM -- 2100 ft AGL

etc

 

For every NM you descend 300 ft.

 

To know if you are at the correct altitude, you must know the distance to the airport.

Usually, at the airport is a DME (Distance Measuring Equipment). You recieve the signal, and can see how far away the airport is.

 

So if the DME tells you you are 5NM from the airport. You do the quick sum 5x300 is 1500. You check the altimiter. Are you much lower?? GO AROUND !!!!

You get the idea....

 

By the way, I believe the correct name for this is not a VOR approach, but a VOR/DME approach.

 

Hope that helps.

What we seem to be talking about here is two kinds of approach navigation- Manual and FMC.

I'm sure there are pilots here who have used the FMC you are using. The FMC *I* use is generic and works with any aircraft.

 

Since you want to use the FMC for approach (I assume it's because you want to land on a runway without an ILS) VOR approaches are a LOT less accurate and require there be a VOR in the center of the airport- some do and some don't) you'll have to use a CHART to get correct altitudes.

 

HOWEVER, most FMCs (mine included) have a mode where you use them for both LNAV and VNAV in which case the FMC does NOT use the VOR for runway alignment, but knows the location, heading and altitude of the runway. In these cases, the FMC will set your VS and guide to the documented runway altitude at a fixed rate but will NOT take terrain or trees into consideration. When *I* use this type of navigation, it's because I have a high confidence I know the terrain and there is no ILS and the weather is obstructing. I will only let the FMC guide me into visual range, then I'll take over as this kind of approach has no small amount of risk associated with it. I use it for emergencies only.

 

A Manual VOR approach is much more straight forward using charts and like the FMC approach, it's used to get you into visual range. If the VOR is significantly offset from the airport center (which somewhere near half or more are) you have to be aware of this and make the appropriate adjustments.

 

So...

We are either talking about a manual VOR approach, or we are talking about keeping your FMS in VNAV mode down to the runway (which is better done if you have a very good plan or STAR loaded) but you are either flying a Manual VOR approach, or you are flying an FMC approach. It's unlikely you are doing both.

 

-Pv-

Thanks,

 

Well...yes. It can use GPS PRIMARY, GPRIS hybrid position, IRS MIX position...etc.

 

Ok, I got it know. Last question: in Airbus, there is no TO/FROM....

So what do I enter in the RAD NAV page basically? A TO or a FROM??? Basically, I can enter any CRS, it will always point an arrow on that CRS (ND - ROSE MODE VOR). And as I turn, the VOR turns with me to show me where I am going (HDG/TRK). So at the end, I am always aligned with my VOR radial straight. I don't know if it was a FROM or TO.....

 

Thanks

Hi

 

Just pause the video when it starts:

 

 

Is he TO or FROM the VOR station?

Understanding when you are flying to or away from a VOR is a fundamental skill taught in the Learning Center and a skill you should have before trying to master an FMC.

 

-Pv-

Yeah...have spent the evening watching videos to understand...

I hope I will be able to understand with this:

 

Is the white arrow with the triangle near the top of the line the TO indication?

Is the white arrow with the triangle near the bottom of the line the FROM indication?

 

Thanks

Understanding when you are flying to or away from a VOR is a fundamental skill taught in the Learning Center and a skill you should have before trying to master an FMC.-Pv-

 

An after of watching videos he still doesn't understand.