**Flight model modifications version 1.14.5.0**

Using the parameters drag_coef_zero_lift, htail_incidence, thrust_scalar and fuel_flow_scalar the maximum airspeed, (L/D)max and fuel consumption can be set to one operating point OP. I set the OP to no flaps, retracted landing gear, full thrust, level flight, no elevator input and altitude 30000 ft.

The book "Quest for Performance: The Evolution of Modern Aircraft" has no data about the DA62. A typical (L/D)max value for DA62 class airplane is 13. The Asobo flight model (L/D)max is 14.9, measured with the MSFS 2020 build-in DevMode tool Aircraft Editor, Debug, Sim Polar VhVs.

MSFS 2020 has no propeller drag and no ground effects. Therefore I reduce (L/D)max from 14.9 to 10.9. A smaller (L/D)max value needs a higher thrust_scalar value for the same level flight cruise speed at sea level. As second workaround I use increased retractable gear and flaps drag.

empty_weight_pitch_MOI = 5216 ; 4688 ; Empty pitch moment of inertia, Jxx (SLUG SQ FEET)

empty_weight_roll_MOI = 5272 ; 5634 ; Empty roll moment of inertia, Jzz (SLUG SQ FEET)

empty_weight_yaw_MOI = 10031 ; 9862 ; Empty yaw moment of inertia, Jyy (SLUG SQ FEET)

"we have developed a tool that computes the MOIs based on the dimensions and geometric shape of the aircraft, now that you have defined everything. You can find the results of these MOI calculations in the Weight [Aircraft Editor] Debug Window"

This is "real" inertia for me.

pitch_stability = 0.04 ; 0.1

roll_stability = 0.04 ; 0.1

yaw_stability = 0.04 ; 0.1

"You need to enter a value that is higher than zero for backwards compatibility with the legacy flight model, and you can enter 0.01 - for example - if you want only the minimum friction. If the plane has more inertia, you can enter higher values."

This is "fake" inertia for me.

flaps-position.0 = 0, -1, 0, 0, 0, 0, 0 ; 0, -1, 0

flaps-position.1 = 20, -1, 1, 1, 0, 0, 0 ; 20, -1, 0.5 ;

flaps-position.2 = 42, -1, 1, 1, 0, 0, 0 ; 42, -1, 1.0

The parameters are Pos (deg), Max Speed (Kts), Drag Coeff, Lift Coeff, Area Coeff, Added Camber, Aft CoL Displacement

wing_incidence = 0 ; 1 ; Wing incidence (DEGREES)

htail_incidence = 2 ; 1.5 ; Horizontal tail incidence (DEGREES)

"You'll want to leave the horizontal tail Incidence at zero for the moment, this value will be used to set the default trim of the aircraft."

Trimmed for OP with no elevator input.

fuselage_length = -1 ; 25 ; Nose to tail (FEET)

elevator_trim_neutral = 0 ; 1.5 ; Elevator trim max angle (absolute value) (DEGREES), for indicators only (no influence on flight model)

This is a green area in the non-cockpit elevator trim display.

parasite_drag_scalar = 1.76 ; 1

drag_coef_zero_lift = 0.03200

"this value is usually of around 0.02 to 0.025 for an aircraft with a glide ratio above 15, 0.03 to 0.04 for aircraft with glide ratios of about 10, and up to 0.1 for some slow bush planes with very low glide ratios."

I use drag_coef_zero_lift as "missing propeller drag" workaround. Normally I only use drag_coef_zero_lift. But you can use parasite_drag_scalar and/or drag_coef_zero_lift. This time I left the Asobo value for drag_coef_zero_lift and changed parasite_drag_scalar.

induced_drag_scalar = 1.5

flap_induced_drag_scalar = 1.5 ; 2

**[PROPELLER]**

thrust_scalar = 1.9 ; 1.15 ; Propeller thrust scalar

Change in drag_coef_zero_lift needs change in thrust_scalar for the same cruise_speed.

ui_autonomy = 7 ; max duration the aircraft can fly between take-off and landing in (Hrs)

fuel_flow_scalar = 0.81 ; 1 ; Fuel flow scalar

Change in thrust_scalar needs change in fuel_flow_scalar for the same ui_autonomy. I use 80% LVR on ground to set fuel_flow_scalar.

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