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Payload distribution

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In the aircraft.cfg saved by payload editor, the second parameter of all station_load lines is zero. Does this mean that the distribution of the payload across the stations has no effect?

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CorrectRegardsBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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It does not seem right... even FS stock aircrafts have the stations distributed; wondering, is there a special reason for such an omission in our paid-for model?

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I consider it less an omission and more a design choice. I made the same conscious decision when I designed my own alternative FDE for the PSS A330/340. Saves the number of e-mails I get from people who have loaded their planes way, way out of limits wanting to know why the autopilot has the jet porpoising like Flipper in the middle of a Sea World marine show.In reality, since FS2004 does not model moment of inertia effects of load distributions, I think it's a reasonable simplification. The effects of CG are not going to be noticeable in a FBW aircraft with hydraulic-actuated flight controls anyway, unless it's so far out of limits that it affects controllability/stability. So by placing the load centroids at the CG, the inertial effects of increased mass are modeled, and the otherwise unnoticeable CG effects are simplified away.CheersBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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Hey Rob. Yeah, it's been many months since I was able to sit down and spend a few whole days devoted to hobby stuff. But it's back into the breech tomorrow, unfortunately.CheersBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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>In reality, since FS2004 does not model moment of inertia>effects of load distributions, I think it's a reasonable>simplification. Looks like you are wrong here.Microsoft support incident Support Request ID SRZ060128001927In a FS-related forum, a respected member claimed that "FS2004 does not model moment of inertia effects of load distributions". Is it true? The forum message is at http://forums.avsim.net/dcboard.php?az=sho...g_id=6152&page={Raghavendra} Thank you for using Microsoft Games online Chat Support. My name is Raghav. {Raghavendra} Vadim, I have visited the link and also found the issue in the problem description. {Raghavendra} According to my research, it seems to be untrue. However, since a Respected member of the Group has posted the message we would need to reconfirm it. {Raghavendra} Would this be in relation to a third party aircraft? {Vadim Rapp} the discussion at the forum - yes, it was about PSS aircrafts. But his statement apparently relates to FS itself. {Raghavendra} Thank you for your patience, Vadim. {Raghavendra} I have researched on this issue and found that the claim is untrue. {Vadim Rapp} So FS _does_ react to the position of the center of gravity. Right? {Raghavendra} Yes, Vadim.

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I think not.FS "reacting" to the position of the CG is not the same issue as modeling moments of inertia of aircraft loads. The CG is a single point--the centroid of all the loading moments on the airplane. MOI refers to the mean distribution of the mass away from the CG...think of it like two equal sliding weights on a bar...as long as they remain the same distance from the center of the bar, the CG remains the same, but the MOI increases as the distances from the bar's center increase...increased MOI means it takes more torque to effect rotation around the CG as the balls are moved further away, and there is more rotational inertia for a given rotational velocity.Movement of a load absolutely affects the location of the CG in FS, but I have yet to observe evidence that a load's MOI...the effect of its distribution...on rotational inertia around any axis is modeled. There is a MOI value specified for the empty aircraft itself...but none for the loads.As an experiment, you can try placing two equal loads on an acft in FS at a great distance in front and behind the CG. As long as they are equidistant from the CG it won't alter the CG's position. It should make it extremely hard to enter or roll out of a turn. Hasn't worked that way yet any time I've tried it.I want something better to refute this than some phone-bank answerdude making $1.35 an hour in India somewhere...RegardsBob ScottATP IMEL Gulfstream II-III-IV-V L-300Santiago de Chile

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