Conflicting altitudes in the IRNMN2 STAR and L24R Approach into KLAX

Hello guys, hope you’re doing well.
I found that the altitudes in the IRNMN2 STAR and L24R Approach into LAX have conflicting altitudes: The lowest altitude for waypoint GADDO in the STAR is 6000ft, but the Approach lists CRCUS (first waypoint) at 12000ft. I deleted the conflicting altitudes from the flightplan and had no issues (other than the aircraft diving at -3000ft to reach a waypoint), but wanted to know if this is a bug or something that happens IRL (that’s why it isn’t on Support). Here are the screenshots:


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Hello some STARs have restrictions like above 10000 but below 15000. In a real aircraft VNAV would compute those to have a nice descent. But on IF we do not have that, so I believe the lowest altitude gets added to the flight plan. Correct me if I am wrong

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Infinite Flight seems to randomly choose between the lowest and highest altitude restrictions - which then often times don’t make sense.

@Sturmovik best way to get around this is to use a flight planner and modify all the altitudes for a proper realistic descent.

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What would have happened if I hadn’t deleted the other altitudes? Would I have been flying lower, way before getting to the airport?

No need to go out that far, you could turn in at merce or kobee which have lower altitudes

Since I had access to charts, I look at it directly and change the values

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typically aircraft on that STAR would get radar vectored, hence, you wouldn’t fly out all the way to waypoint CRCUS.

CRCUS is 37.3 DME from the airport. you would never fly that far our IRL, they would turn you a lot sooner and clear you a lot lower

on the STAR chart, it says “expect radar vectors to final approach course”
Screenshot 2024-03-07 174504

for the Localizer 24R approach, it would be much more likely to be vectored to the final approach fix (FAF) of KOBEE or just before it to established about 10-15nm out instead of the published 37.3 DME at CRCUS)

If I was flying this, I would turn in and descend to probably ~4k and join the final approach course at MERCE to give me time to get established and stabilized

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looking at the chart, the 6k is correct, as well as the 12k is correct on L24R approach. So the “random altitudes” isn’t not really a factor in this situation.

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Perfect, I’ll have to keep checking the charts instead of blindly following the data from IF. Still, the CRCUS part is on me, I didn’t know which waypoint to choose for my approach and randomly added that one. I’ll be sure to select other waypoint next time.

Thanks to all!

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CRCUS is what’s called an IAF, an initial approach fix. you could start your approach there, but ATC will often vector you shorter. You must be established prior to the Final Approach Fix (FAF), marked by a Maltese cross (picture attached). for this approach, that is KOBEE
Screenshot 2024-03-07 175701

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For cases like that, you have to file it as ‘Vectors to Final’ and fly a vector course from the final waypoint of the STAR to the first waypoint of the approach.

In this case, CRCUS is a waypoint on the ANJLL arrival, used to segue traffic straight from the STAR onto the approach course.

If you tried to fly that approach from the IRNMN arrival to CRCUS, you would probably fly into a mountain.

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Got it, I’ll do so next time I fly into LAX. Should vectors to final be chosen every time I file a flighplan?

Depends on your STAR. You don’t always have to file Vectors to Final, but if you’re not sure than it is probably better to file it instead of some out-of-place IAF fix.

Some provide IAF fixes (such as CRCUS and TRNDO) to link directly into approaches.

Usually, if filing from the west (when LAX is on west flow), use the ‘vectors to final’ transition for your approach. The only exception is the GOATZ and DIRBY arrivals, which link directly into TRNDO (which segues into the ILS Runway 25L approach).

If filing from the east under the same circumstances, use the SEAVU IAF transition for the HLYWD or SEAVU arrivals or the CRCUS IAF transition for the ANJLL arrival (if arriving from the southeast, use the OLAAA arrival to TRNDO instead of the SNSTT arrival to SEAVU).

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Many thanks for the detailed info, I’ll redo my flight and fly with vectors to final.

Top right is ANJLL, Center right is HLWYD/SEAVU, bottom is OLAAA and GOATZ/DIRBY, top left is IRNMN/HUULL.

The points where the colors change are the IAF approach fixes.

NOTE: on the northwest arrivals, vectors to final are usually provided instead of the procedural turns showed in the RNAV-RNP approach for 24R. The 25L approach is the ILS/LOC approach. Also, CLPUR is an offload transition, not to be filed by any aircraft.

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This bit interests me, could you please explain? I keep wondering if I been filing my STAR and Approaches wrong now lol

I don’t think the colors actually mean anything. Like I said, it’s where the STAR splices into the Approach.

What do you mean by Splices into the approach?

Leads directly into. There is no space in between.