Inadequate ILS Localizer range in-game, Less than value in BGL/XML for Stock Airport

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Are you using Developer Mode or made changes in it? No

Brief description of the issue: Stock ILS localizer default range is 27 nm, in-game range is much less at 15 nm.

Provide Screenshot(s)/video(s) of the issue encountered: Any ILS with IF/IAF waypoints beyond 15 nm unflyable.

Detail steps to reproduce the issue encountered: For example, KGPI ILS 02 IF/IAF GOGGS is included in stock approach, and is as published; however, ILS localizer is not received at 21 nm and aircraft will fly by the approach.

Did you submit this to Zendesk? If so, what is your ticket #? 122794

This limitation has global effect, no approaches with waypoints beyond 15 nm can be flown.

This isn’t really that far off. The normal range for a real world ILS localizer is 18nm though there are some that are certified for a longer range. You also have to consider that the localizer antenna is at the far end of the runway so runway length has to be considered. In your example, Rwy 2 is 9001 feet long. Let’s call it 1.5 nm to keep the math simple. It’s 15.1 nm from JOLEK to the runway threshold. That’s 16.6 nm total when you add in the runway length. GOOGS is an RNAV waypoint and not a localizer waypoint.

However, your point is taken that the default range for a localizer specified in the SDK, if no other range is defined, is 27 nm. Things may be different in other parts of the world, but in the US using 27 nm for the default range would be incorrect.

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KGSO 23L comes in right at 27 miles for me. You left out whether you have anything in your Community folder. I’m guessing you do. If so, move it to your desktop and try again.

GOGGS is indeed an ILS waypoint, defined in the ILS approach. A “normal” range for an ILS actually depends on the design of the approach and the results of the flight test. I base this on 23 years USAF ground electronics experience including NAVAIDS, and four decades of active flying.

If an approach is TERPED for a 21 nm waypoint to act as IAF then flight check is going to verify the localizer accuracy and signal strength at 21 nm plus a wide margin for safety.

Thanks, I’ll check that out.

Start at KDAN - it’s a direct shot into the 23’s at KGSO.

You’re spot on. I removed the Navigraph add-on and now receive the localizer at GOGGS as expected. Oops… I know better too. Oh well, time to complain to Navigraph.

I beg to differ. Look at the symbol for GOGGS and compare it to the symbol for JOLEK. JOLEK is a triangle. That indicates it’s based on the localizer. The symbol for GOGGS is a star. That symbol indicates that it is an RNAV waypoint and not based on he localizer. Just because it’s on the extended centerline doesn’t mean it’s identifiable with the localizer signal.

Yes, when you fly to GOGGS. But how would you get from GOGGS to JOLEK? By picking up the localizer at GOGGS, and if you cannot do that the approach is broken.

You fly the 020 RNAV FROM course until you receive the localizer.

It most certainly is identified with the localizer, while I agree it is defined by FAA with lat/lon rather than radial/dme information nonetheless it is still an ILS IAF and while the notes on the chart indicated DME required (probably for the missed approach holding fix) and RNAV-1 or RADAR is required for the procedure entry (the procedure turn), no such requirement exists to fly from either of the IAF’s FIKAB, OLIBY o SKOTT (all of which are defined with dme/radial information) where no procedure turn is required. It is absurd to think the localizer doesn’t extend to GOGGS. There is no requirement to have RADAR or GPS when entering from those IAF’s.

Your opinion is noted. I disagree with it, but nothing I can say will change your mind.

The more I thought about the RNAV-1 requirement for procedure turn entry I think I got it: The RF definition for GOGGS would include the localizer at the intersection of FCAr217 and think about it. The FAA defines the course width for the localizer to be 4.0 deg, which at 21 nm is going to be about a 3 nm wide localizer and then try to define that with a VOR radial at 20 nm where the radial has a permissible error of +/- 4 deg and you get the reason the holding pattern course reversal is based on a GPS waypoint. The errors using RF would be just too great. That doesn’t mean there is no localizer, it only means the localizer is pretty wide way out there and TERPS approach design requires more stringent error margins.

For what it’s worth, the real I-GPI localizer has a flight checked usable distance of 30NM.