Thank You Mark... this post needed that ....now everyone who took the time to read your post will be that much smarter. thanks againTyler

Thanks Mark a really good explanation. Just have one doubt. Where are the sensors located?Just to add something. The CIVA INS has a SDK, so it could give the geo position the problem is how to feed this info in to the PMDG and what will happen if the information is cut.Jos

So when someone says "hey, IRS ain't important, the bird's got GPS", its only half the story. The actual position information from the IRS is just one product. The other data is just as (or even more) important!! A rivot is important wouldn't you agree Mark? The fact of the matter is this is not a real aircraft, if we were talking about a real aircraft then everything is important but since it is not, stating that a pilot's interaction with the IRS on the NG is simple as looking up the FMC GPS position makes a lot of sense. A rw pilot does not interact with an actual IRS unit as much as people on forums proclaim plain and simple. Not to mix up facts here as I also desire anything that can be simulated on the NG for fs but show me one aircraft with EVERYTHING IMPORTANT simulated which of course used in such context implies everything there is....Best Wishes,[h4]Randy J. Smith[/h4]http://www.rawbw.com/~bdoolin/shinault/southparkcartmad.gif[h3]PMDG 747![/h3]Caution! Not a real pilot, but do play one on TV ;-)ASUS KV8 DLX | AMD 3200 64 | 1 GIG PC 3200 DDR | GIGABYTE 5700 ULTRA | ViewSonic VP192b 19" |

Thanks for a great post, Mark(and for answering my question. :-)).BR,Frank

Hi guys!Thanks for the kind feedback!"Where are the sensors located?"I believe (I've never actually seen an IRS box) all sensors are within the IRS unit itself which is most probably located somewhere in the E&E bay. The IRS doesn't require remote sensors."problem is how to feed this info in to the PMDG and what will happen if the information is cut."Exactly. So for it to function the PMDG team would have to start programming on the 737 again. Time frame: if all goes well, I'd say around 1 week. If problems arise - who knows ;-) maybe up to 2 months or so. So I really doubt there will be an interface for something that isn't that realistic for the any 737, yet alone for the NG.Regards,Mark

I wonder if rugerdog will be posting again?- Ken Salter

"The actual position information from the IRS is just one product. The other data is just as (or even more) important!!"Hi Mark,I think the full name for this unit is ADIRS(Air Data Inertial Reference System).See the enclosed pic from the 737 Flight Manual.BR,FrankEDIT: Apologies for posting as a zip, but it was the only way I could get it to work! /F

Yeah, in the 737 its an integrated piece of hardware. It consists of an air data (AD) and the IRS part (IRS) combined (ADIRS).On other aircraft, these systems are divided up. You have an ADC (air data computer) and an IRU (IR unit).Why this was done like this, I don't know. I guess one reason could be to save space and keep the cables short (the data exchange between ADC/IRS can be incorporated) as the IRS needs TAS info to compute wind and the ADC needs IRS info to compute vertical speed. (and I guess a few other things aswell?)Regards,Mark

Yes, that rant certainly put him in his place rugerdog, not!!!!These forums are an airing place for news, opinions, requests and ideas. They are not to be used as an infantile argument venue for flaming other users. Indeed far from irritating the author of the post you were referring to, I think the most likely result of your post will be your banning from the avsim forums. Before you give it the old "VA sticking together" speech, might I add that I do not know John either personally or indirectly. The only "juvenile play" aspect of this thread has been your pointless irrational post. Feel free to come and track me down whenever you please.

As usual I believe that is a matter of choice and priorities, PMDG choose not to model the IRS. Personally I would like to see the IRS. True that in normal operation could be an undetected system, same happens with CIVA INS, however the effects in abnormal operation should be interesting to follow to say the least.Jos

Hi,For those of you interested the updated version of CIVA INS available at http://www.SimuFly.com/ins is quite interesting. The inertial Navigation System gauge is fully working and model accurately the real thing.I have been testing it for several days now without a glitch. Attached is a picture of a sub-panel I created for CIVA INS which can be opened from the PMDG Overhead panel. Ok the background BMP of the sub-panel is not up to the PMDG standards but at this stage the main focus was to get inertial navigation available in the PMDG. We all know that publication of modified cfg files cannot be done without the approval of PMDG so please refrain to ask me for a modified cfg file. Let me assure you that one does not need a PhD to make the necessary adjustments, it is fairly straight forward.Have a shot at it it is worth the study.Michaelhttp://forums.avsim.net/user_files/98665.jpg

"Also, they included a backup IRS mode. This requires a short alignment period (around 30 seconds) and will restore attitude information. You can also enter heading info but this will drift quite fast. But no AP, no track, no map, no V/S..."Are you sure about the V/S, Mark ? ;-)Cheers.Ian

"RE: Inertial Navigation system Nameless, The Idea of the PMDG product is to provide realism. Using an INS is the most rediculous things I have ever heard. And bring the DF727 into it will not change that fact.John"John, Your comment was VERY rude and insensitive to the original author of this thread. I personally think it's up to each individual as to the amount of customized tweaking he/she chooses to do with their own particular 737 installation. As the current PMDG 737 does not simulate a functioning IRS system at all, it might add more realism for some users to install the Delco gauge and go through the alignment procedure as part of a pre-flight checklist, if nothing else.Frankly, this would be more realistic than not interacting with an IRS system at all as real 737 flightcrews of course do.

Hey Ian,I had this discussion going on over at pprune aswell :-)It seemed as though Airbus'es actually were able to get V/S data from static information alone, but I'm pretty sure that you won't have V/S info on the 767 without IRS input.I'd say you need both static and IRS information for the V/S to be reliable.What do your tech notes say?Regards,Mark

Diane, Frank,Thanks for the nice words. It is rewarding, also to read some really good posts made by people who really master this tricky part of aviation. If some of us can learn a bit, can exchange expertise, can get answers to questions then this thread is not as ridiculous as some may think.ThanksMichael