NOTAM #5: Socata TB20GT

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Reports have come in that the Trinidad will ungracefully do a 'doggy squat' at the end of a pushback. This is unacceptable!After much head scratching among the engineering staff, a six year oldwandered in the hanger this evening, and asked what the problem was.After explaining the situation, the smart alec kid pointed out that ifwe change one little number, the tendency to 'dog squat' woulddisappear...static_cg_height=3.1Simply edit aircraft.cfg to have the static_cg_height closer to thelength of the main gear!Problem solved. We strongly urge all Socata TB20GT owners to completethis little edit as soon as possible. It will also be incorporated into the '90 Day Service Release' due out in mid-February.BillFounder, Director ofCreative Recycling of Aircraft PartsF.A.R.T.S.

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This is one that has been confusing me.What is the difference betweenstatic_cg_height=3.500and the vertical componenent inempty_weight_CG_position=-2.000, 0.000, -1.000?And why is there astatic_pitch=3.020if the inherent balance of the a/c is defined by its CoG and position of landing gear (pivot point)?My only guess is that when you initially start FS, the a/c is sort of dropped onto the ground to balance around CoG and if you preset the static pitch you do not get a 'bump' as the a/c settles (such as a tailwheel).Steve

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>This is one that has been confusing me. >What is the difference between >static_cg_height=3.500static_cg_height=x.xxxThe static height of the aircraft when at rest on the ground, in feet. The program uses this value to position the aircraft at startup, in slew, and at any other time when the simulation is not actively running.This parameter is one which is most often misunderstood, since it actually has no bearing whatever on the a/c while in motion; hence, the name "static." This value is the distance in feet from the ground to the COG point in the model. It should be at least equal to or greater than the length of the main gear, as measured from the bottom of the tire to the pivot point of the gear (in the case of retractables), or the mounting point of fixed gear.The main gear points in the Socata's .cfg are specified as -3.15', so the static height originally set to 2.01 was effectively moving the static_cg_height much too low; hence, the tendency to 'dog squat' (i.e. tail strike) when ending a pushback movement. :(Increasing the static_cg_height=3.1 eliminates this aberant behavior. Once the a/c is in motion, this value becomes meaningless and isn't used at all.static_pitch=x.xx determines the angle in degrees the nose will 'pitch up' when in slew mode. Setting this value to 1.0 or less than 1.0 is more than adequate.>and the vertical componenent in >>empty_weight_CG_position=-2.000, 0.000, -1.000 "Offset (in feet) of the center of gravity of the basic empty aircraft (no fuel, passengers, or baggage) from the Reference Datum Position."There are three separate points defined in any model.1) Center Point of Model:The model's Flight Simulator center point, which is on the centerline

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>The model's Flight Simulator center point, which is on the centerline

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>>The model's Flight Simulator center point, which is on the centerline

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