Duplicate fix definitions

[hazzas-99]

What is in error?

Certain fixes have been duplicated in the sector file.

The task:

• Find where they're defined
• If it's a fix related to an IFP (Instrument Flight Procedure) at an airport, then it should be in Airports/EGxx/Fixes.txt - generally, fixes are defined on charts/in RNAV coding tables with greater precision than they are in ENR 4.4
• If a fix is defined at an airport level but also features in ENR 4.4, then add a commented line to Navaids/FIXES_UK.txt stating where it is defined
• If it's a fix on an FIR boundary that has duplicate definitions in UK and Non-UK, define in UK if it's featured in ENR 4.4, or Non-UK if not. Ideally, cross check the coordinates with the local AIP to ensure they're still correct.

Fixes are:

• [ ] NEVRI
• [ ] OSDEB
• [ ] TUFOZ
• [ ] ZOPHI

Sources

Various

File changes

TBC

[PLM1995]

Found where these 4 are:

NEVRI - Navaids/FIXES_UK.txt and Airports/EGTE/Fixes.txt OSDEB - Navaids/FIXES_UK.txt and Airports/EGKK/Fixes.txt TUFOZ - Navaids/FIXES_UK.txt and Airports/EGKK/Fixes.txt ZOPHI - Navaids/FIXES_UK.txt and Airports/EGKK/Fixes.txt

If it's a fix related to an IFP (Instrument Flight Procedure) at an airport, then it should be in Airports/EGxx/Fixes.txt

Forgive me trying to get my head round this but do IFPs include SIDs and STARs? If so, surely it makes more sense to have all ENR 4.4 fixes in Navaids/FIXES_UK.txt since some are common to many procedures (e.g. BEDEK and NIGIT). Lots of the fixes in ENR 4.4 seem to be used by STARs and SIDs.

generally, fixes are defined on charts/in RNAV coding tables with greater precision than they are in ENR 4.4

Both seem to have 2 decimal place second precision to me? However, the Navaids/FIXES_UK.txt file seems mostly to use whole second precision. I doubt it makes much practical difference, but if there was an easy way to import all the data from ENR 4.4 it might be worth considering a full update of Navaids/FIXES_UK.txt ?

Sorry if I have missed something, just trying to understand.

Thanks, Peter

[hazzas-99]

@PLM1995 Yeah IFPs do include SIDs and STARs, but generally they are defined to a greater level of precision on RNAV charts and in coding tables than is provided in ENR 4.4.

A full update of ENR 4.4 is on the cards in #4016

1. NEVRI - this should definitely not be duplicated in the EGTE Fixes.txt file, as it's a fix in Northern Ireland. That can be safely removed from Airports/EGTE/Fixes.txt, but I would then just check we have all fixes for the two RNP approaches at EGTE correctly
2. OSDEB - this should be defined in FIXES_UK.txt only, but we should use the more precise version that is in ENR 4.4 - 505654.53N 0002447.85E
3. TUFOZ - same again, define in FIXES_UK.txt but amend to 510101.01N 0003024.31W
4. ZOPHI - and again, amend to 510126.60N 0000055.43W