fmc?

Default FMS/FMC/CDU, whatever you wanna call it or perhaps even the possibility of INS navigation, is a far shot in my opinion.

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Really?

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Yeah, it would be nice with an MD-80 with INS NAV in FSX.

The there is one available for FS9 though, the Flight1 Super 80.

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Funny, I thought I saw that it had INS NAV at their website. Oh well..

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Could there be a chance they made a typo? (ONS) "O" is right next to "I"...

LOL...!!

Joking..

I dont care its a simulator/computer game you should fly the plane manualy aney way if not, it just becomes a spectator sport, and I will be back to playing other stuf in no time thats if thats what the thing your talking about dose.

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Yeah...what he said 
Very well put Vololiberista, couldn't have said it better myself 
/Nexus (who only gets yelled at when trespassing into goteborg CTR)

Talk about an old topic.

Concerning the FMC, would that be that difficult to import the iFly 747 FMC gauge into another airplane or into FSX ?

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TRUE! What I have been studying/listening in school(Advanced Navigation) the FMC(Flight Manegment Coputer) is like the INS(Inertial Navigation System). Basically you put the RWy, destinations, waypoints, altitudes, and ect. ect. ect. to fly with it you simply turn on autopilot and select nav in this case in order for the computer to fly you, and not you fly it Its amazing what I have learned over 6 months in flight school haha

TR

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HAHAHAHHA

Sorda!!

Katahu, using the FMC is highly recommended. It really is your friend. If nothing else, even on manual, it can tell you useful info like showing graphically how much ground distance your plane travels to descend or ascend to a target altitude as well has saving flight information for you such as updated GW to name a few.

Mike Ray says in his boeing books that the CDU is the "Control Display Unit" which is the actually keyboard and screen of the FMC. The FMC is the actual computer, maybe the "box" under the dual CDU's. But he also said many call them the same thing. If you suddenly had to take over a 747/737, the FMC would be one of the first tools to consult for navigating to a prospective airport for landing.

Aren't there other Addons with IRS? such as the LDS767? or the Flgiht 1 ATR-72. The PFD doesn't even show correctly until the IRS are calibrated(may take 10 minutes).

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The old INS systems did take "time" to cross check and calibrate themselves. They also needed frequent crosschecking in flight by the pilots.  However, they were a HUGE advance on DR!

PS I challenge Katahu to fly from London Heathrow to Hong Kong "without" INS GPS VOR or NDB solely by using DR!!!!!
Vololiberista

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In that case, I wouldn't end up in Hong Kong, I would most likely end up in Antarctica since I don't even know what DR stands for.

IRS don't have to be calibrated but aligned...
they are gyros systems, and as such before being the accurate navigation system they are the gyros have to speed up to a certain speed ,where they become "rigid". which mean that there spining axis is always in the same position in respect of stars, ie whatever movement did the plane do, and even the earth, the spin axis is always pointing to the same direction.
when the A/C move calculations take place and process the actual A/C position + many other parameters. it just needs to be fed with the actual A/C position while aligning.
for that reason A/C must not be moved during the alignement process.

INS are based on the same principle but use accelerometers fixed to the frame of the aeroplane. every single movement is caused by an acceleration in different axis. this acceleration is measured and integrated one time to get a speed, and a second time to get a distance. again they need to be aligned, and you need to tell the "thing" what's its actual position during alignment. then you have an initial position, an acceleration, a speed and a distance, which is far enough to compute the actual position.

add to this few Air Data Computer which will process, from static pressure and pitot pressure, many parameters like speed, altitude, vertical speed...

feed all the informations computed by the IRS/INS, ADC to the FMC and then you have an extremely accurate and powerfull tool to navigate.

to understand and use these systems need A LOT of reading and training, and one may not feel the need to use them when others may will to master them. both are respectable.

myself I prefer flying manually ...

If PMDG can do it, MS should be able to do it too... then it would probably be a great added value to FSX. for virtual airline, for example....

my two cents.....


vince

Thebrelon, IRS does indeed have accelerometers aswell, since gyros alone cant give any measurement  of the aircraft's movement through space.

Another valuable note: the IRS today aren'y really used as a navigation platform.  The FMC on modern airplanes are certified to navigate accurately with  VOR/DME and GPS. The FMC always assumes that radio position is more accurate than IRS, always.

What the Inertial Reference does provide is to sense and compute linear accelerations and angular turning rates about every axis. This data is used for pitch and roll displays.

You need to not move the aircraft during alignment because the IRS/INS automaticly assumes acceleration during alignment is due to the Earth's gravity, and the only motion during alignment is because of the Earth's rotation.

This phenomena explains why it takes so much longer to align the IRS/INS close to the poles, where rotation is much more slower, compared to the equator.

No commercial aircrafts have inertial systems that can be aligned during motion afaik. However the Military has had it for years (in submarines, for example). That's how it used to be, may very well have changed since my books were printed. 

The laser gyros are indeed a huge improvement compared to their mechanical counterparts.
The ring laser gyros consume less power, generate less heat and also decrease alignment time. That combined with  accelerometer improvements has resulted in significant decrease in weight, size and cost and of course, increase in reliability.

Simply put; inertial accuracy is a direct function of technology, The more sensitive accelerometers, the more stable the gyros, and the more sophisticated the torquing software and hardware...the more accurate the system

Also had a healthy debate about ring laser here
http://www.simviation.com/cgi-bin/yabb/YaBB.cgi?board=paywaregen;action=display;...


Think we're moving slightly off topic 

Laser Gyros do indeed drift, watch after a flight the IRS position, and compare it to the FMC position, they will always disagree (not by much though!) And even during flight, the individual IRS position will disagree, sometimes more, and sometimes less.

However depending on the hardware and software set-up you can eliminate drifting down to <1 nm during a flight.

Effects that are compensated for are schuler-tuning, coreolis effect, coning, sculling etc.
Stuff that really doesn't belong here