RNAV Departure in A320 (A32NX)

[David McClanahan]

I'm fluent with A320 controls and IFR and RNAV landings (STARs Approach etc.)

What is and how to fly a RNAV Departure?  I was in KPHL and positioned and ready for takeoff when ATC wanted me to confirm RNAV Departure.

I didn't know what this was, and first time I'd heard it (i have about 30 flights on A320 in VATSIM).

I replied no and was told I needed to confirm RNAV Departure ... so I cancelled  and exited.

I've not found a good tutorial on youtube , only 1 reference to RNAV Departure on A320 and it didn't cover the departure in the video.

Where can I learn this? thanks 

[Robert Shearman Jr]

If you had filed an RNAV SID which is completely pilot-nav, they probably wanted you to confirm your first waypoint.  For example in Atlanta your takeoff clearance might be "SWA123, RNAV to MPASS, runway 26L cleared for takeoff." and reading back your confirmation that MPASS is your first programmed point and you're going to turn toward it immediately upon takeoff is a mandatory part of reading back your takeoff clearance.

Note that the Atlanta example is from memory so I may not be consistent about the point name and the runway, but hopefully that answers your question anyway.

Edited July 26, 2021 at 02:32 AM by Robert Shearman Jr
Hey! Turns out 26L and MPASS are indeed correct if you filed, for example, the JACCC2 departure. Take a look at it if you want to see!

[Ryan Geckler]

It's anytime parallel runway departures are being used - this way, you verify that you're flying the correct procedure off of the correct runway.

[Alistair Thomson]

Surely if the readback of the clearance by the pilot is given as per Rob's post, there is nothing further to be done?

[Tobias Dammers]

On 7/24/2021 at 10:35 PM, David McClanahan said:

What is and how to fly a RNAV Departure?

A SID that is defined in terms of RNAV waypoints rather than conventional navigation methods.

In a conventional SID, instructions tell you things like "fly heading X", "until X DME ABC", "intercept radial 123 from VOR ABC", etc.: things that a conventionally equipped aircraft (one or two NAV radios, an ADF, and one or two DME's) can navigate.

An RNAV SID basically just tells you the waypoints to fly to, and those waypoints are defined as geo coordinates (latitude & longitude) and part of your onboard FMS database. To fly an RNAV SID, your aircraft needs to be RNAV-capable, which includes having an FMS and an up-to-date nav database. Practically all modern airliners are RNAV-capable, and at least in Europe, even the majority of bizjets and IFR-certified GA aircraft are.

As to how you fly it: in a modern airliner like the A320, it's pretty much exactly the same as a conventional SID, and you may even have flown a couple RNAV SIDs without realizing it: you program the SID into the FMC, and then you just follow the magenta line (or whatever color it is in the airbus). And at some point you'll turn on LNAV and let the aircraft follow the magenta line automatically. Whether that lines is defined from RNAV waypoints or from conventional navaids doesn't make much of a difference.

[Lauri Uusitalo]

KPHL seems to not have "real" SIDs, only PHL2.PHL. On it there are no routes but just VORs. And a note "expect radar vectors for first navaid/fix".

So if ATC asks for RNAV departure, does that mean that they will not provide you with radar vectors, but expect you to manage to get there on your own?

 

ps. I guess this was what Robert said...

[Kirk Christie]

This is an americianism, I am not aware of anywhere else that confirms rnav to fix with take off clearance.

This is probabbly because rnav from the end of the runway is newish, where previouslly it was vectors to the first fix.

I am not sure of the purpose of the phraseology, some one can probabbly confirm, however, would would expect that you have already accecpted and confirmed you will fly an Rnav SID when you readback your Airways clearance.

[Andreas Fuchs]

11 minutes ago, Kirk Christie said:

This is an americianism, I am not aware of anywhere else that confirms rnav to fix with take off clearance.

Dublin EIDW does this, too: "report first waypoint on your FMS" is a standard question there before you are allowed to depart. I also had this at another airport in Europe, I do not remember where exactly anymore, been flying too much recently.

[Alex Ying]

7 hours ago, Lauri Uusitalo said:

KPHL seems to not have "real" SIDs, only PHL2.PHL. On it there are no routes but just VORs. And a note "expect radar vectors for first navaid/fix".

So if ATC asks for RNAV departure, does that mean that they will not provide you with radar vectors, but expect you to manage to get there on your own?

 

ps. I guess this was what Robert said...

As you mentioned, PHL has no pilot-nav SIDs. Note that whether a SID is pilot-nav or radar vector or hybrid (combination of the two) is independent of whether it's RNAV or conventional. You can have RNAV radar vector SIDs and conventional pilot-nav SIDs. It is more likely that a pilot-nav SID Is also RNAV, but not a rule.

That said, PHL has no RNAV SIDs so I'm not sure if something was lost in translation in the original post. Every aircraft taking off from PHL gets radar vectors to their first fix.

[Alistair Thomson]

9 hours ago, Alex Ying said:

Every aircraft taking off from PHL gets radar vectors to their first fix.

Ah. Now there's the rub. Will we soon be taking about the state of Denmark? (Sorry, I have an education which includes Shakespeare, and I can't seem to shake it off)

[Lauri Uusitalo]

16 hours ago, Alex Ying said:

That said, PHL has no RNAV SIDs so I'm not sure if something was lost in translation in the original post. Every aircraft taking off from PHL gets radar vectors to their first fix.

So what would be the reason for mentioning anything about RNAV in the clearance?

[Andreas Fuchs]

Maybe a misunderstanding?