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G-SWSM

Aircraft Shaking.

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Hi.I have an add-on from Alphasim, the Handley Page Victor Tanker K2 that tends to shake and I wondered if anyone knew what could be causing this, and if it is fixable.For instance. I take off and retract the gear etc, then start the climb to FL150, but during this climb and at 250kts the aircraft starts to shake.The only way to stop it is by reducing the speed to 200kts.Anyone have any thoughts.Thanks.

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250 kts is a bit low for a military jet aircraft to get the "shakes". I believe the Victor is capable of an IAS in excess of 300 kts at altitude and and a true airspeed over 560 kts.Sometimes premature "shakes" in MSFS can come from the MOI being too low in one or more axis in the aircraft.cfg. A good FDE should produce them as the aircraft approaches it's VNE, but it's sometimes hard to get "just right" in the sim. I'd suggest increasing the MOI value, starting with the pitch axis since that's where it's often too low, until you can fly at cruise altitude, cruise airspeed without any sign of the shakes. Just take note of what's there in case my advice doesn't help.One consequence of increasing the MOI is you would need more elevator, aileron or rudder authority, depending on the axis changed due to the heavier forces needed to overcome the higher MOI value. Thus you might want to also visit the flight tuning section and up the sensitivity for the axis you do change.Hope this helps.Regards,John

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Hi John.Many thanks for the helpful points.I was wondering if you might be able to show me where I should be looking to try and rectify this problem.I will post the aircraft cfg below, and make a safety backup before altering anything.[weight_and_balance]// ACM V2.0max_gross_weight = 238000empty_weight = 95127reference_datum_position = 0, 0, 0empty_weight_CG_position = -0.05, 0, 0empty_weight_pitch_MOI = 1521051empty_weight_roll_MOI = 687115empty_weight_yaw_MOI = 1634207empty_weight_coupled_MOI = 0max_number_of_stations = 6station_load.0 = 180.0, 38.430, -1.700, 3.330station_load.1 = 180.0, 38.440, 1.530, 3.310station_load.2 = 180.0, 33.920, -0.160, 3.970station_load.3 = 180.0, 35.660, 1.530, 3.400station_load.4 = 180.0, 35.760, -1.710, 3.410station_load.5 = 21000, 0, 0, 0[lights]//Types: 1=beacon, 2=strobe, 3=navigation, 4=cockpit, 5=landinglight.0 = 3, -17.68, -57.00, 1.10, fx_navredm ,light.1 = 3, -17.68, 57.00, 1.10, fx_navgrem ,light.2 = 3, -56.20, 0.90, 14.45, fx_navwhi ,light.3 = 3, -56.20, -0.90, 14.45, fx_navwhi ,light.4 = 1, 14.80, 0.00, -3.35, Fx_shockwave_beacon_rotating_red ,light.5 = 1, 22.50, 0.00, 8.20, Fx_shockwave_beacon_rotating_red ,light.6 = 2, 38.75, 0.00, 6.50, fx_probe,light.7 = 2, 39.55, -0.00, 6.20, fx_probe,light.8 = 2, -40.00, 1.70, -1.70, fx_probe,light.9 = 2, -40.00, -1.70, -1.70, fx_probe,light.10 = 2, -11.00, 3.70, -2.00, fx_probe,light.11 = 2, -11.00, -3.70, -2.00, fx_probe,light.12 = 2, -14.90, 45.125, -0.40, Fx_shockwave_landing_light_small_xenon,light.13 = 2, -14.90, 44.25, -0.40, Fx_shockwave_landing_light_small_xenon,light.14 = 4, 39.00, 0.00, 3.50, fx_vclightlight.15 = 3, -17.68, -57.00, 1.10, fx_shockwave_strobe_sm ,light.16 = 3, -17.68, 57.00, 1.10, fx_shockwave_strobe_sm_2 ,[GeneralEngineData]//0=Piston, 1=Jet, 2=None, 3=Helo-Turbine, 4=Rocket, 5=Turbopropengine_type = 1fuel_flow_scalar = 1.823engine.0 = -11.0, -12.201, 0.0engine.1 = -11.0, -8.287, 0.0engine.2 = -11.0, 8.287, 0.0engine.3 = -11.0, 12.201, 0.0min_throttle_limit=0.000000[smokesystem]smoke.0 = -4, -14, 8, PSS_smokeyvlsmoke.1 = -4, -14, -8, PSS_smokeyvlsmoke.2 = -4, -14, 12, PSS_smokeyvlsmoke.3 = -4, -14, -12, PSS_smokeyvl[effects]wake = fx_wakewater = fx_spraydirt = fx_tchdrtconcrete = fx_sparkstouchdown = fx_tchdwn, 1contrail = fx_contrail_l[fuel]//Longitudinal (feet), Lateral (feet), Vertical (feet), Usable(gallons), Unusable (gallons)fuel_type = 2number_of_tank_selectors = 1LeftMain = 0, -10, 0, 2560, 0LeftAux = 0, -20, 0, 1875, 0RightMain = 0, 10, 0, 2560, 0RightAux = 0, 20, 0, 1875, 0electric_pump=0[contact_points]static_pitch = 0.2static_cg_height = 6.17max_number_of_points = 13point.0 = 1, 20.189, 0, -6.55, 2250, 0, 1.3, 35, 0.1, 7, 0.85, 5, 5, 0, 235, 270point.1 = 1, -2, -15, -6.8, 2500, 1, 2, 0, 0.5, 2.5, 0.85, 5, 5, 2, 235, 270point.2 = 1, -2, -18.5, -6.8, 2500, 1, 2, 0, 0.5, 2.5, 0.85, 5, 5, 2, 235, 270point.3 = 1, -2, 15, -6.8, 2500, 2, 2, 0, 0.5, 2.5, 0.85, 5, 5, 3, 235, 270point.4 = 1, -2, 18.5, -6.8, 2500, 2, 2, 0, 0.5, 2.5, 0.85, 5, 5, 3, 235, 270point.5 = 2.0, 0.536, -26.347, -4.420, 1574.803, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 5.0, 0.0, 0.0point.6 = 2.0, -23.071, -57.989, 0.567, 1574.803, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 5.0, 0.0, 0.0point.7 = 2.0, 0.550, 26.517, -4.415, 1574.803, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 6.0, 0.0, 0.0point.8 = 2.0, -22.987, 57.988, 0.602, 1574.803, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 6.0, 0.0, 0.0point.9 = 2.0, -29.843, 0.0, -3.122, 1574.803, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 9.0, 0.0, 0.0point.10 = 2.0, -40.846, 0.0, -2.028, 1574.803, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 9.0, 0.0, 0.0point.11 = 2.0, 27.523, 0.0, -4.523, 1574.803, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 4.0, 0.0, 0.0point.12 = 2.0, 45.101, 0.0, -0.431, 1574.803, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 4.0, 0.0, 0.0gear_system_type=0[keyboard_response]elevator = 150.0000, 250.0000aileron = 150.0000, 250.0000rudder = 150.0000, 250.0000[forcefeedback]gear_bump_nose_magnitude = 1000gear_bump_nose_direction = 18000gear_bump_nose_duration = 250000gear_bump_left_magnitude = 2000gear_bump_left_direction = 35500gear_bump_left_duration = 250000gear_bump_right_magnitude = 2000gear_bump_right_direction = 500gear_bump_right_duration = 250000ground_bumps_magnitude1 = 1250ground_bumps_angle1 = 8900ground_bumps_intercept1 = 5ground_bumps_slope1 = 0.48ground_bumps_magnitude2 = 450ground_bumps_angle2 = 9100ground_bumps_intercept2 = 0.075ground_bumps_slope2 = 1crash_magnitude1 = 2000crash_direction1 = 1000crash_magnitude2 = 2000crash_direction2 = 9000crash_period2 = 7500crash_duration2 = 2500000stick_shaker_magnitude = 2000stick_shaker_direction = 0stick_shaker_period = 111111[airplane_geometry]//ACM_AREAW1// 0,0,0,7.0103,1.9134,1.9134,1.4723,8.1323,3.8269,3.8269//ACM_AREAW2// 2.9449,9.2543,5.7403,5.7403,4.4175,10.3760,7.6538,7.6538,5.8899,11.4982//ACM_AREAW3// 9.5670,9.5670,7.3625,12.6203,11.4806,11.4806,8.8350,13.7423,13.3942,13.3942//ACM_AREAW4// 10.3072,14.8641,15.3077,15.3077,11.7798,15.9862,17.2212,17.2212,13.2524,17.1082//ACM_AREAH1// 0,0,0,3.3222,0.5536,0.5536,0.5648,3.7211,1.1073,1.1073//ACM_AREAH2// 1.1296,4.1199,1.6611,1.6611,1.6949,4.5187,2.2146,2.2146,2.2599,4.9176//ACM_AREAH3// 2.7685,2.7685,2.8248,5.3165,3.3222,3.3222,3.3898,5.7154,3.8759,3.8759//ACM_AREAH4// 3.9546,6.1142,4.4295,4.4295,4.5198,6.5131,4.9833,4.9833,5.0847,6.9120//ACM_AREAV1// 0.0208,0.0208,0,2.9753,0.3804,0.3804,0.3804,3.3594,0.6966,0.6966//ACM_AREAV2// 0.7608,3.5727,1.0131,1.0131,1.0131,3.8926,1.3078,1.3078,1.3078,4.0847//ACM_AREAV3// 1.6030,1.6030,1.6670,4.3193,1.8981,1.8981,1.9407,4.5966,2.1932,2.1932//ACM_AREAV4// 2.2785,4.9380,2.4453,2.4453,2.5309,5.2153,2.5269,2.5269,2.7404,5.3003//ACM_CAREAW1// 8.6106,8.6106,10.1314,11.5333,9.5670,9.5670,10.8676,12.1996,10.5240,10.5240//ACM_CAREAW2// 11.6035,12.8655,11.4806,11.4806,12.3402,13.5319,12.4375,12.4375,13.0761,14.1981//ACM_CAREAW3// 13.3942,13.3942,13.8127,14.8641,14.3507,14.3507,14.5488,15.5304,15.3077,15.3077//ACM_CAREAW4// 15.2852,16.1965,16.2644,16.2644,16.0214,16.8626,17.2212,17.2212,16.7576,17.5286//ACM_CAREAH1// 0,0,1.6611,3.3222,0.5536,0.5536,2.2260,3.8041,1.1073,1.1073//ACM_CAREAH2// 2.7911,4.2859,1.6611,1.6611,3.3559,4.7680,2.2146,2.2146,3.9210,5.25//ACM_CAREAH3// 2.7685,2.7685,4.4860,5.7319,3.3222,3.3222,5.0510,6.2136,3.8759,3.8759//ACM_CAREAH4// 5.6160,6.6957,4.4295,4.4295,6.1809,7.1774,4.9833,4.9833,6.7459,7.6595//ACM_CAREAV1// 0,0,0.8557,2.5678,0.3804,0.3804,1.2359,2.8111,0.7608,0.7608//ACM_CAREAV2// 1.6167,3.0546,1.1411,1.1411,1.9972,3.2980,1.5216,1.5216,2.3775,3.5415//ACM_CAREAV3// 1.9019,1.9019,2.7578,3.7850,2.2825,2.2825,3.1384,4.0286,2.6628,2.6628//ACM_CAREAV4// 3.5188,4.2719,3.0432,3.0432,3.8991,4.5155,3.4237,3.4237,4.2796,4.7589wing_area = 2597.0wing_span = 120.0wing_root_chord = 21.630wing_dihedral = -1.0wing_incidence = 2.8wing_twist = -1.0oswald_efficiency_factor = 0.912wing_winglets_flag = 0wing_sweep = 37.580wing_pos_apex_lon = 28.640wing_pos_apex_vert = 0.0htail_area = 263.100htail_span = 32.700htail_pos_lon = -44.340htail_pos_vert = 0.0htail_incidence = -1.0htail_sweep = 45.560vtail_area = 75.080vtail_span = 7.160vtail_sweep = 45.0vtail_pos_lon = -33.020vtail_pos_vert = 6.030elevator_area = 189.432aileron_area = 201.420rudder_area = 42.500elevator_up_limit = 28elevator_down_limit = 20aileron_up_limit = 19.481aileron_down_limit = 14.897rudder_limit = 23.491elevator_trim_limit = 10.500spoiler_limit = 59.989aileron_to_spoileron_gain = 0.0min_ailerons_for_spoilerons = 0.0min_flaps_for_spoilerons = 0.0spoilerons_available = 0[electrical]max_battery_voltage = 24generator_alternator_voltage = 28max_generator_alternator_amps = 50electric_always_available = 1flap_motor = 0, 5, 0gear_motor = 0, 5, 0autopilot = 0, 5, 0avionics_bus = 0, 10, 0avionics = 1, 5, 0pitot_heat = 0, 2, 0additional_system = 0, 20, 0marker_beacon = 1, 2, 0gear_warning = 0, 2, 0fuel_pump = 0, 5, 0starter1 = 0, 20, 0light_nav = 0, 5, 0light_beacon = 0, 5, 0light_landing = 0, 5, 0light_taxi = 0, 5, 0light_strobe = 0, 5, 0light_panel = 0, 5, 0[TailHook]tailhook_length=4 tailhook_position = -15.0, 0.0, -1.0 cable_force_adjust = 1.0[TurbineEngineData]fuel_flow_gain=0.002 inlet_area=4.908 rated_N2_rpm=29920.0 static_thrust=20600.0 afterburner_available=0 reverser_available=0[Views]eyepoint=38.5, -1.5, 4.9 [autopilot]autopilot_available=1 flight_director_available=1 default_vertical_speed=800 autothrottle_available=1 autothrottle_arming_required=1autothrottle_takeoff_ga=0autothrottle_max_rpm=99.0000pitch_takeoff_ga=8.0000 max_pitch=10.0000max_pitch_acceleration=1.0000max_pitch_velocity_lo_alt=2.0000max_pitch_velocity_hi_alt=1.500000max_pitch_velocity_lo_alt_breakpoint=20000.0000max_pitch_velocity_hi_alt_breakpoint=28000.0000max_bank=28.0000max_bank_acceleration=1.800000max_bank_velocity=3.0000max_throttle_rate=0.100000nav_proportional_control=9.0000nav_integrator_control=0.250000nav_derivative_control=0.0000nav_integrator_boundary=2.500000nav_derivative_boundary=0.0000gs_proportional_control=9.520000gs_integrator_control=0.260000gs_derivative_control=0.0000gs_integrator_boundary=0.700000gs_derivative_boundary=0.0000yaw_damper_gain=0.0000 [exits]number_of_exits=1exit_rate.0=1.0 use_no_default_pitch=1use_no_default_bank=1[Radios]// Radio Type=availiable, standby frequency, has glide slopeAudio.1=1 Com.1=1, 0 Com.2=1, 0 Nav.1=1, 0, 1 Nav.2=1, 0, 0 Adf.1=1 Transponder.1=1 Marker.1=1 [direction_indicators]direction_indicator.0=3,0 [Tailhook]tailhook_length=6.7tailhook_position=-19.5,0.0,-1.6cable_force_adjust=1.0[Reference Speeds]flaps_up_stall_speed=125.0 full_flaps_stall_speed=100.0 cruise_speed=461.644 max_indicated_speed=600.000000max_mach=0.979980[General]atc_type=HANDLEYPAGEperformance=Model: Phil PerrottnPanel: Phil PerrottnFlight Dynamics: J. McDanielnTextures: Phil PerrottnnLength: 114 feet 11 ins.nSpan: 120 feet 0 ins.nEmpty Weight: 95,127 lbsnGross Weight: 238,000 lbs.nPower: 4 x Rolls-Royce Conway RCo.17 Mk 201 turbofans, 20,600 lb. static thrustnRange: Maximum 4,600 miles with 21,000 lbs payloadnTop Speed: 640 mph @ 40000 ftnMax Cruise: 625 mph @ 40000 ft editable=1 [Flaps.0]type= 1span-outboard= 0.500extending-time= 20.0system_type= 1damaging-speed= 250.0blowout-speed= 300.0lift_scalar= 1.130drag_scalar= 0.600pitch_scalar= 0.500flaps-position.0= 0.0, 0.0flaps-position.1= 5.0, 225flaps-position.2= 17.250, 185[Flaps.1]type= 1span-outboard= 0.250extending-time= 20.0system_type= 1damaging-speed= 250.0blowout-speed= 300.0lift_scalar= 0.567drag_scalar= 0.300pitch_scalar= 0.250flaps-position.0= 0.0, 0.0flaps-position.1= 9.0, 225flaps-position.2= 35.0, 185[brakes]toe_brakes_scale=1.000000parking_brake=1[gear_warning_system]gear_warning_available=1pct_throttle_limit=0.099976flap_limit_power=25.496622flap_limit_idle=5.042029[hydraulic_system]electric_pumps=0engine_map=1,1,1,1normal_pressure=3000.000000[stall_warning]type=1[attitude_indicators]attitude_indicator.0=1[turn_indicators]turn_indicator.0=1,0Many thanks again John.

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You want to adjust these values. They do look pretty low to me given the aircraft weight and speeds. I would start by adding a million to each value. If the shakes go away, then reduce the values by 100K until the shakes appear at VNE (if you can get actual VNE info for the aircraft). It is not mandatory you reduce the adjusted MOI until the shakes appear, this but it helps realism if you can get the aircraft to misbehave as you near or exceed VNE.:empty_weight_pitch_MOI = 1521051empty_weight_roll_MOI = 687115empty_weight_yaw_MOI = 1634207Afterwards if control seems sluggish, add this section below and increase the effectiveness values for the elevator, aileron and rudder:[flight_tuning]cruise_lift_scalar=1.000parasite_drag_scalar=1.000induced_drag_scalar=1.000elevator_effectiveness=1.000aileron_effectiveness=1.000rudder_effectiveness=1.000pitch_stability=1.000roll_stability=1.000yaw_stability=1.000elevator_trim_effectiveness=1.000aileron_trim_effectiveness=1.000rudder_trim_effectiveness=1.000

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