Hello again gents,I need some help with this AIRAC business. I'm not clear on everything contained in an AIRAC cycle. Consequently I'm not sure how important it is to update the cycle from the originals that come with the PMDG products. Should I get the latest cycle from Navigraph? Apparently Dan Downs has developed some related helpful data provided through AVSIM...would it provide the same information as the latest AIRAC cycle from Navigraph? Also Planepath provides a download that updates the FSX database. Do I need that? Sorry guys but obviously I'm totally lost in all this info. I'm trying to learn but I need some help to get started in the right direction.Any help much appreciated,Eric Olson

Hi Eric, like yourself Im not fully clear in all the aspects of Airacs but they are of great benefit in getting from A to B in the FMC. I personally use Navigraph which serves me well, but there is a slight minus if you are not careful. The Navigraph data seems to run in parallel with good quality addon airports in particular regarding ILS frequencies which are up to date, however the MSFS airport data in the MAP section is in a lot of cases not accurate as it has never been updated by MSoft, so I would suggest checking the MSFS data with the Navigraph data and see if they agree as the FMC data might be rejected by the MSFS data making a flight more testing. You can check this before loading a flight. Someone with more knowledge than me is likely to correct my post. richard welsh

Good questions Eric. I had a long article on this in the old pmdg wiki but I don't think it got into the knowledge base.There are two elements to AIRAC infomation: 1) NAVDATA which is global in nature and defines airports, runways, ILS info, NAVAIDs, airspace fixes and airways; and 2) SIDSTARS which is local in nature and defines terminal procedures for one airport including SIDs STARs and IAPs (Instrument Approach Procedures). This information is slightly interrrelated such that the SIDSTAR runway info needs to agree with the NAVDATA runways or you can't use the SIDSTAR. That is the main reason to keep both elements in the same cycle.Navigraph provides both elements in their FMS Data.Other guys like Terry Yingling (planepath.com), Steve Bell with virtual BA and myself provide SIDSTARs. We do it strictly as a hobby and free to you, and these replace a few of the SIDSTARs that you get from Navigraph, which provides SIDSTARs for virtually every ICAO location that has published procedures in the world.The basic AIRAC cycle is 56 days, which is a standard chart cycle as well. Data is updated every 28 days; thus, not all cycles are equal. This year the major updates will come out on the even cycles such as the next one (1008). The off cycles are usually just military changes.As richard mentioned, the MFSF navdata is obsolete and is never used by the pmdg aircraft except when you have to such as runway numbers, ILS and VOR frequencies, etc. All of this changes over time, even runway numbers, and MS didn't provide an realistic way to update their global data so we are stuck with this but it is really just an inconvience. You have to update sceneries if you want the new runways (KSEA KORD among many others), and you have to check the MSFS Map data if you are not getting the ILS to see it it uses a different frequency, which is then easily changed manually in the FMS.I recommend keeping current AIRAC, or at least every other cycle, just so you can fly the same routes and procedures as the real guys.Hope this helps.

Yeah, the cycle that comes with our planes is pretty old at this point. If you want to fly real routes as found on sites like flightaware, you're gonna need the latest navdata. You can get a full year of updates for every addon they support from Navigraph for like $20, I think it's well worth it. Then just install Dan's files or whatever else you like over top of the navigraph stuff and it'll update those airports that have been customized.

Thank you Dan, Richard and Ryan.Eric Olson

Hi,I was just wondering if Dan (Downs) has stopped doing the procedure updates, as I have not seen any in the past few cycles. I have tried other sources, but none has come close to the quality of the updates that Dan provided.Just curious.

Hi,I was just wondering if Dan (Downs) has stopped doing the procedure updates, as I have not seen any in the past few cycles. I have tried other sources, but none has come close to the quality of the updates that Dan provided.Just curious.

Yeah he's taking a hiatus from it due to some personal issues, he let me know a few months ago that it would be a while before he continued his files.

I wonder why I find that some SIDS and Stars are older versions, missing or not correct. How does Navagraph obtain their data? Thanks,

Navigraph purchases the data, and I have not found any older versions in any of the US locations that I pay attention to; however, if there is an error it will be fixed and a revision issued in most cases. Just let them know of the error in their forum.

Yeah he's taking a hiatus from it due to some personal issues, he let me know a few months ago that it would be a while before he continued his files.

Very sorry to hear that. Hope all turns out ok.

I went to PLANEPATH.COM and I couldn't find anything there on airac cycles it was moe like a listing for dif sim's but no AIRAChis TERRY'S THAT IS USE TO BE EASY TO UNDERDTAND NOW IT'S FUBAR!!!!

CAN SOMEONE JUST E-MAIL ME A OLD AIRAC CYCLE i CAN'T EVEN USE MY CITATION when I installed in WIN 7It kocked out the nd files and all my flight info for the FMC! [email protected] P.S. Idon't fly online so it don't matter how old it is!!! THANK YOU

Full names in this forum please, and the shouting is not necessary. Navigraph has an old cycle available for download free. Hmmm, Cessna Citation? This is a pmdg forum, not sure if that makes a diff to you.