Transition Help. How to know which and when.

[Rich Heimlich]

X-plane 11 has a new default FMS. I'm trying to adapt to it after years of flying with the very rudimentary FMS of the Dash 8. This new FMS supports transitions.

 

My issue is that they're a mystery to me. Take, for example, my last flight:

 

KCLT to KATL

+HUG3 DEBIE ODF WHINZ4

 

Both the SID and the STAR had options to select a transition, but all the points looked foreign to me. I skipped selecting one.

 

How does one figure out if a transition is called for and which one is correct?

 

Is there a resource for this info or is it a case of looking over the details of each piece of the flight to stitch it together? Would someone be willing to fill me in on the right transitions for the above flight as an example ([Mod - Happy Thoughts]uming they are used on this flight) to learn from?

 

Thanks.

[Bradley Grafelman]

The TL;DR is: read the chart.

 

"HUG3.DEBIE" is the "DEBIE TRANSITION" as described on the second page of the chart.

 

On the other hand, "ODZ" isn't a transition on the WHINZ4 - it's actually the common fix, hence why you see (ODF.WINZ4) in the corners of the chart (or under the chart name if you're using Jepp's charts).

 

Not all SIDs/STARs have transitions, and of the ones that do, you don't necessarily have to use them.

[Dace Nicmane]

Is there a resource for this info

Yes, charts.

 

https://skyvector.com/files/tpp/1705/pdf/00078HUGO.PDF

https://skyvector.com/files/tpp/1705/pdf/00078HUGO_C.PDF

https://skyvector.com/files/tpp/1705/pdf/00026WHINZ.PDF

 

The HUGO3 departure is a vectored departure to your first waypoint, DEBIE, it doesn't have any additional waypoints. The transition is for aircraft without FMC as you can see from the description.

 

On WHINZ4 arrival, since you're joining it at ODF, you don't need any transition. If you were joining it at SPA, MOL or SOT, you'd use the appropriate transition to ODF.

[Bradley Grafelman]

The HUGO3 departure is a vectored departure to your first waypoint, DEBIE, it doesn't have any additional waypoints. The transition is for aircraft without FMC as you can see from the description.

Not sure what your last sentence means - the route is agnostic of whether or not you have an FMC. "HUG3.DEBIE" means the same thing to an Airbus A380 as it does to a Piper Cub.

 

In this case, it's an actual transition on the chart. Namely, "From over CLT VOR/DME on CLT R-255 to DEBIE." In theory, the departure controller could just say something like "cleared direct Charlotte, resume (the departure/the DEBIE transition/own navigation)." I'm guessing it's more likely that you'd instead be vectored to join the 255 radial... but that's besides the point.

[Dace Nicmane]

In theory, yes. But in practice, they don't [Mod - Happy Thoughts]ign non-RNAV procedures to RNAV aircraft. At least on VATSIM.

And they wouldn't make you turn back to the airport (CLT VOR) unless you're departing to the East (only rwy 5) and need to turn back anyway.

[Rich Heimlich]

So trying to decipher this from manual reading of the charts (and help from above), I see that HUG3 leads to DEBIE and that, thus I would choose the DEBIE transition.

 

Here's where I'm curious/confused. I didn't select a transition in my FMC to fly this last route and it seemed to work just fine. I took off, hit NAV and the plane followed HUG3 to DEBIE. How would choosing the DEBIE transition on the FMC changed anything? Or is this just a specific case where the transition option is identical to the "non-transition" path?

[Bradley Grafelman]

Not sure what this means:

the plane followed HUG3 to DEBIE

 

Here's a more illustrative example. Take the VTU7 SID out of KLAX. If you were cleared for "Ventura Seven departure, DINTY transition, ..." and didn't select DINTY as a transition in your FMC, you'd fly a route you weren't cleared to do. The clearance was for "VTU7 DINTY" but you'd be flying "VTU7 VTU DINTY". The "Ventura Seven departure" with no transition takes you to the common fix of VTU. After that, you'd be heading direct to DINTY. That would look like this:

 

 

Notice how you'd be flying right through a restricted area - R-2519. Oops!

 

Now, had you selected the DINTY transition in your FMC, it would fly the cleared route of "VTU7 DINTY" (e.g. from over VTU you'd be direct SUDDO then direct DINTY) and would instead look like this:

 

[Dace Nicmane]

The DEBIE transition would take you to CLT first.

[Rich Heimlich]

Thanks guys. This is a great help. Much to digest and to try out yet.

[Randy Tyndall 1087023]

The DEBIE transition would take you to CLT first.

 

Well, technically...no. The DEBIE Transition would take you to...DEBIE. The HUGO3 Departure would take you to Charlotte VOR.

 

Randy

[Rich Heimlich]

Does anyone know if the online plan sites, like SimBrief and such, include transition data in their plans where called for or is this generally not part of a plan?

[Bradley Grafelman]

What do you mean by "transition data"? All of the pertinent information about flying a given transition will be contained on the chart, not sure why sites like SimBrief would try to reiterate it.

[Rich Heimlich]

In other words, do any of the sites supply a flight plan that includes the transition information in the text?

 

From above comes the exxample of "HUG3.DEBIE".

 

So, would I find that a site might say: HUG3.DEBIE ODF WHINZ4 or will it just say HUG3 DEBIE ODF WHINZ4 and I figure out the transition from the chart?

 

Sorry for the slow uptake, but this is brand new to me.

[Bradley Grafelman]

The waypoint listed adjacent to the procedure name specifies what you're doing, whether that be the common fix for that procedure or one of its listed transitions.

 

The VTU7 chart example above shows that the common fix for the VTU7 SID is VTU ("VTU7.VTU"). If you have a route that doesn't have "VTU" following VTU7, then you're using one of its transitions. Thus "VTU7 DINTY" implies the "DINTY transition." A route of "VTU7 AVE" would be nonsenical; "AVE" isn't the common fix on the departure and the chart describes no "AVE transition."

[Rich Heimlich]

In the case of KPHL to KDCA a popular flight plan is as follows:

 

DQO V166 BELAY TRISH CLIPR CLIPR1

 

In this scenario I come into CLIPR1 at BELAY, I believe. MDX is a listed transition on the CLIPR1 STAR chart. So is BELAY thus a transition or must transitions be listed on the chart as MODENA is on this chart?

[Bradley Grafelman]

In this scenario I come into CLIPR1 at BELAY

Technically, you don't. Both BELAY and TRISH are just random waypoints that precede the STAR portion of your route. After TRISH, you proceed direct to the common fix, CLIPR, and begin the CLIPR1 arrival at that waypoint.

 

The CLIPR1 arrival only has one published transition - from MXE - and you aren't using it. Thus, you're using the common fix (CLIPR) and everything before that fix is just random waypoints from your flight planned route that aren't related to the STAR.

[Rich Heimlich]

Thanks. That brings a lot of clarity... Much appreciated.

[Dace Nicmane]

In any case, listen to your clearance whether you're given a transition or not. Also, make sure you don't just hit NAV when given a turn and direct but turn first roughly in the direction of the waypoint, because if you turn left instead of right, you can mess things up for ATC, also you can end up at an awkward angle to turn onto your next leg.

[Robert Shearman Jr]

The period is just a style preference. Most FMCs list procedures with it; most flightplans show a space there instead. But whether or not the dot appears, the waypoint given immediately after the SID is the SID transition, and the waypoint immediately before the STAR is the STAR transition.

 

Sometimes they're the same point... i.e. KBWI PALEO3 ENO KORRY3 KLGA. Smyrna VOR (ENO) is both the transition out of the PALEO3 and into KORRY3.

[Bradley Grafelman]

Smyrna VOR (ENO) is both the transition out of the PALEO3 and into KORRY3.

Technically it's only the "transition" on the PALEO3. For the KORRY3, ENO is the common fix (e.g. none of KORRY3's three possible transitions are used in that route).

[Robert Shearman Jr]

Smyrna VOR (ENO) is both the transition out of the PALEO3 and into KORRY3.

Technically it's only the "transition" on the PALEO3. For the KORRY3, ENO is the common fix (e.g. none of KORRY3's three possible transitions are used in that route).

Yeah, what he said ... lol.