Thanks for the tip!Terry

This inertial navigaton system was used on the 1970's era aircraft. Nice add-on for the 747-200...Don't think it has any bearing on inputing this rudimentary nav system on an advanced 737NG....But, I guess if you want to put glass-packs on a 2005 Chrysler 'Pacifica', you can do anything you want....Go for it..Regards,jack

Hi With the INS will it be able to make the screens on the 737ng look like this: http://www.airliners.net/open.file/518242/L/ with the attitude indicator blank. if so I am definently gettin it but if not would there be a way to do it? ThanksTyler

Tyler,the screens on this a.net pic look this way, because the plane is on the ground and most of the systems are shut down. This has absolutely nothing to do with an INS.Wolfgang

>I have been testing it for several days now without a glitch.>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.First, i concour with the others saying this thing (the Delco Carousel Mk IV) has absolutely nothing to do with any 737, let alone the NG.Second: to let this thing actually fly the plane, you have to disable the PMDG autopilot.What is the pro of this?You end up with an old prehistoric system and without the original autopilot...I don't get it :(

Wolfgan,Tyler has probably just been confused between the term IRS and INS.John http://homepage.eircom.net/~eamonnmca/images/logo_ba.JPGwww.bavirtual.co.uk Senior Captain Simflight.com Staff Reviewer

Using an INS system is WAY more fun then the 'press and forget' FMC. I believe this INS system is what is being used in DF's new 727.

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 http://homepage.eircom.net/~eamonnmca/images/logo_ba.JPGwww.bavirtual.co.uk Senior Captain Simflight.com Staff Reviewer

Hi,By posting the link to an accurate INS I did not think there would be such an uproar. So let me clarify a few things.1. It was not the intention nor was it indicated in my original post to let people think the INS was a standard instrument of the NG series.2. A good INS and this one is full featured, is an excellent way to deepen knowledge on how inertial navigation works and this topic may be of interest to some people.3. I thought, but from the comments read I prove to be wrong, that one could have fun going through some technical aspects of navigation even if this instrument is considered by many as an antiquity.I sincerely apologize for the confusion.Michael

yes I was actually talking about the IRS but I always thought they were just different ways to say it. Wolfgang, I was in a 737NG a few moths ago and I asked the pilot why the screens looked like that and then he said it was because the IRS was off and then a bit later he switched the IRS mode selector to NAV and then everything looked like normal. but INS might be diferent then IRS...I dunno. Tyler

Well hey I am all for tweaking if one wants to do it.. Regarding the IRS, as any rl pilot will tell you, FMC GPS position ;-) that's not to say it would not have been nice to have the IRS only it is NOT as big a deal as some proclaim it to be..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" |

Hi Michael,I, too, am mystified by the 'uproar'(and irritated by some of the replies to your original post, one, at least, of which was both disingenuous and disdainful). There is certainly no need to apologise as far as I am concerned! Sure, there was a little bit of confusion - I thought, hey, I'm off to get that, being the one major system not modelled in the NG, until I realised we were not talking about the IRS, after all. :-) However, the post was interesting in itself, and I, for one, learned from it.Best wishes,Frank

Tyler,I must admit, that sometimes also I mix up those 2 instruments.Wolfgang :-)

Is an aircraft with an inoperative IRS allowed to depart?BR,Frank

There seem to be quite a few misunderstandings here.Let me have a go at it:First of all, IRS (inertial reference system) is not the same as INS (inertial navigation system). The basic idea behind the two is identical, but while the IRS is newer (technology wise) the INS can actually do more.INS: A mechanical instrument that is aligned during preflight in a stationary aircraft. From this point on, it can drive the different flight instruments, give the autopilot instructions and tell you which way to go. A INS usually consists of the following panels in the cockpit:1) a mode select unit (where you switch it on/off) and2) a CDU (not a FMS CDU!) where you can enter positions and read off tracks. The CDU is not very complex, only a few buttons and a small display. Nothing fancy.IRS: The IRS has almost no moving parts. It senses movement through something called "doppler effect" ie frequency change during acceleration. (basically the same effect you experience if a police car drives by you with its sirens on, only with light instead of sound waves). The IRS can also drive instruments and the autopilot aswell as other systems (yaw damper for example) but it can not be used to navigate directly. That is to say, you can't tell the IRS where you want to go. It will have no idea how to get there either. That's where the FMC comes into the game. It has the necessary mathematical "knowledge" to be able to calculate how to get from A to B. The IRS is "only" used to get the current position data.That's just a very basic explanation of what these two boxes do.As for what happens when the unit(s) break(s) down:The 737 has 2 independent IRS's. (The more IRS's you have, the more accurate your position is and the more redundancy you have). If both of 'em fail (or are switched off) you'll have a very busy time. You'll lose manyr primary flight instruments (attiude, heading, track, Map display, vertical speed...), as the IRS is the (sole) source for them! Also, your autopilots will trip offline as they need IRS data to know how to fly. Unfortunately, the same thing happens if the IRSs lose their alignment (due to a _temporary_ power cut). What's worse, these somewhat older IRS units can not be fully aligned in the air (modern units can, such as those used on hyper-modern business jets). Luckily, the engineers took some precautions:the IRS can be supplied electrically by almost anything. From batteries to the generators - even if the actual battery wwitch is off... (That's why its important to switch off an IRS otherwise it will drain your battery after shutdown!)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...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!!Coming back to the CIVA INS unit: unfortunately, I don't think there are any interfaces so that the INS can actually drive the AP/flight instruments. And as such you can't do a lot with it on the PMDG bird.But if you definetely want to add it, make sure you only add 2 units :-)Kind regards,MarkEDIT: to answer the question above:On some aircraft (where 3 units are installed) you can dispatch with an inoperative IRS unit as long as you aren't gonna fly an ETOPS leg and you don't intend to make a CAT III landing! (remember, inop IRS means inop AP means reduced autoland capability!)