I know this seems bizarre me asking for help but I have a problem updating the m4.csv file to correct many wrong transition altitudes.

The file resides in the RC4x\data folder and is a plain text file starting with a version number on row 1 followed on row 2 onwards by an ICAO, unknown value, transition altitude.

Taking one example of LEMG which needs changing from 6000 to 13000 I have created a new m4.csv replacing the original.

But when loading a flight plan the TA shown on the Controller page for the departure airport of LEMG sometimes shows the old value of 6000 and sometimes the new one of 13000.

But where LEMG is the arrival airport the TA is always 6000, not 13000.

I'm struggling to understand why this is happening. The TA is not stored in the plan so where is RC4 getting it from? Does anyone who understands the structure of RC have an answer?

Don<t know about RC4, but more with CSV files.

What program did you use to create a new file?

Excel for example might modify the original CSV file.

Let me know

Pierre

Pierre,

I used Microsoft Access to import the original m4.csv and a new file containing updated TAs.

After merging the data in Access I exported the data as a csv.

I then edited it with Notepad++ to add the first line - the version number.

I’m well versed in producing text files from Access and know not to do any editing of csv files with Excel.

It’s really baffling. If there was anything wrong with the file structure RC4 wouldn’t be able to read it. But it does but with variable success on getting the TA from m4.csv.

The existing one has been moved out of that folder.

The problem may be resolved.

I created a new plan from GCTS to LEMG and loaded it into RC4. The correct TAs were loaded.

I suspect it may have been a buffer issue relating to data stored in rcv3.dat.

I'll do further checks before releasing the updated m4.csv.

FWIW, that first "unknown value" in the M4.csv entries looks to be the max elevation of terrain in the vicinity of the airfield...looks like it takes into account terrain within 10nm or so.

54 minutes ago, Bob Scott said:

FWIW, that first "unknown value" in the M4.csv entries looks to be the max elevation of terrain in the vicinity of the airfield...looks like it takes into account terrain within 10nm or so.

Thanks Bob. Having checked a few airports I agree that seems to be the case. I haven't changed any of those values.

I've just landed at Malaga and I'm happy that RC4 enunciated all the correct instructions for a TA of 13000ft.

A few more checks and I'll upload a revised m4.csv.

1 minute ago, Ray Proudfoot said:

I've just landed at Malaga and I'm happy that RC4 enunciated all the correct instructions for a TA of 13000ft.

Just curious. Where do you get this updated info? To be honest, I just accept what it gives me.

1 hour ago, IanHarrison said:

Just curious. Where do you get this updated info? To be honest, I just accept what it gives me.

It’s available via Little Navmap apparently but a friend supplied me with the info. I couldn’t find it.

It’s when you use another program like Aivlasoft EFB which has TAs you realise some of RC4’s are wrong. Try a flight into or out of Malaga - LEMG. RC says 6000 but it’s 13000.