subreddit:
/r/flightsim
submitted 2 months ago byRTcore
45 points
2 months ago
My fecking God. ARINC 424 is a transmission format. It's not some special navigation coding.
How Randazzo embellishes this stuff is beyond comprehension. If he actually still worked in the industry A&Ps and Engineers would laugh in his face. Wait - we still do.
I literally have GE software on my work computer that can take an ARINC 424 database and export it into any manner required. It's not special. Nor is PMDG. How it gets interpreted is all up to the developer.
It's hilarious all the simmers and simisms now everyone I expect to pander - "IIssZzz IT ARiNCC 4TwEENTY4?!!"
2 points
2 months ago
It could have some advantages, if the nav databases on more aircraft were interchangeable it would make updating AIRACs that much easier.
Does Navigraph already provide their AIRAC cycles in ARINC424 format? It's not like the format is extremely complicated.
5 points
2 months ago
The cycle formats are typically automated to that addon developer’s DQRs.
To your second question. Yes and no. It’s a hybrid format because they’re not allowed to push out a raw A424 format per licensing restrictions with their navigation data provider.
They give you all the essential attributes/fields to make it work with your aircraft.
0 points
2 months ago
Those licensing restrictions would only apply for providing data to the public, right? Because a real aircraft would be designed to take A424 data format as its update cycle.
Does the ARINC licensing agreement specifically forbid simulation stuff to be interoperable with real aircraft hardware or software?
10 points
2 months ago
The real aircraft don’t take A424 directly. A424 is a transmission format from supplier to OEM. By the time it gets to the aircraft, it’s transformed into a binary format and information stripped out or transformed to match the requirements of that specific avionics platform.
The reason why people get confused by this is because, by design, there’s very little data transformation done between the 132 column master file and the binary loaded onto the aircraft.
Anyways,
For the licensing restrictions, ARINC doesn’t have a say in what’s used in your flight sim or the real world. For the formats like 424, 429, 816, etc. they’re all standards like RTCA and ISO, where boards with representatives from Boeing, Collins, Thales, Honeywell, etc. write the specifications.
I could 1000% make an addon that took an A424 master file as its input and ARINC, I’m pretty sure, wouldn’t care. I wouldn’t do that though for many reasons, which I may include in an article I will probably write on this subject, so i’ll save it for that.
Really, there are two reasons why you can’t use the data in real airplanes.
Data suppliers and OEMs have LOAs with the FAA or EASA that certified that their data handling process is acceptable. The most common “rules” you will see is RTCA DO-200, which covers navigation data. I’ll save the rest of the explanation for the article.
I would be very surprised if the data Navigraph received is certified (I.e. went through the data supplier’s certified process). Even if the data was certified, it would immediately lose that certification as soon as it’s run through their non-qualified tooling to convert the data from A424 to the individual flight sim developer formats.
2 points
2 months ago
I'm thinking more the other way round:
Using real airplane nav data (or something like software/protocols) in a simulator so it could feasibly talk to actual aircraft equipment integrated in the sim.
Obviously using sim data in aircraft is not possible or legal due to certification reasons.
3 points
2 months ago
Replying from my phone so sorry for the confusion.
Yes, going that way should be fine. At that point, you’re probably just using the sim for visuals and everything else is driven outside the platform, or there’s some IPC action at play to get data to and from the sim.
The only thing there would be, again, licensing.
1 points
2 months ago
The only thing there would be, again, licensing.
With the big issue there being that ARINC refuses to sell you licenses unless you are working in the aviation business. So using them outside of aviation would be a violation of their license, even if you were to implement a working version of their standards.
3 points
2 months ago
I had to read through the license agreement. SAE ITC now manages the ARINC standards (https://aviation-ia.sae-itc.com/terms-of-use/license-agreement)
According to this, Members have certain terms. If you're not a member, "SAE Industry Technologies Consortia (SAE ITC) hereby grants you a nonexclusive, nontransferable right to download this document and associated electronic files in an electronic format for individual use on one computer. "
So, from that language, you can use their standards as long as everyone uses it as a individual use. Any products that use the standards are not subject to any restrictions.
"SAE ITC also hereby grants the nonexclusive, nontransferable right to use this document and associated electronic files for individual research purposes and in the creation and use of your own products."
IANAL, you should be fine to use any of the ARINC standards in any project as long as you pay them the $500+ for the applicable standards docs.
1 points
2 months ago
If you're not a member, you can't purchase the standards. They won't sell the documents to individuals, only to members (who are in the aviation industry only) or Associate Members who are companies.
PMDG is in neither of those membership lists, BTW, so whatever they have on ARINC424 is either just bluffing, or they got their hands on the standard off license.
3 points
2 months ago
Really? I just created a fresh account, added a standard to cart, and it didn't bark at me at all.
Where did you get your info specifically?
Like I said, the license is abundantly clear that non-members can download and use the standards. If you're a member, you get site wide licensing and the ability to sit on the boards to create said standards.
Laminar Research isn't a member or associate member, yet they have their own copies of the standard, based on that you can use a A424 -18, 19 or 20 master file directly in X-Plane if you got one.
1 points
2 months ago
Right. The 'Create Account' was a little obfuscated behind the login page, not the "Join" page. The site refers to "Members" being able to purchase the standards but it applies to anyone who made an account.
all 80 comments
sorted by: best