Note from the author: Please upvote https://forums.flightsimulator.com/t/workaround-for-missing-propeller-drag-please/368300

Please check out ring and phylon race mods from thokio and Jacob at
https://flightsim.to/file/8803/airrace-spielberg-austria-redbull-type
https://flightsim.to/file/7950/airrace-new-york
https://flightsim.to/file/7487/grand-canyon-airrace
https://flightsim.to/file/2703/grand-canyon-racing-course

This is no livery, this is a flight model mod. The idea is to make the flight behavior more realistic. One important detail is a realistic glide ratio. Now you can flare your airplane before touch-down.
See http://www.andreadrian.de/FS_2020_sailplanes/ for more of my work for MSFS 2020:
Gliders: SG-38, Aircreations 582SL
Sailplanes: DG-808S, Ka 6E, ASK23
Trainer: Tiger Moth
Seaplane: Grumman Goose G21A
Warbirds: Fokker Dr1, North American P-51D
See Youtube videos https://youtu.be/siRfDWePNqE , https://youtu.be/HE-1hyqK11Q and https://youtu.be/mM-X0VXHZ30

Flight model modification version 1.14.6.0, date 2021-04-05:

I included "Uwa's lighting mods" from https://uwajimaya.github.io/FS2020/
Uwajimaya, I credit your work!
Pack version 1.13 (Feb 16, 2021)

This flight level mod sets (L/D)max to 60% of the real life value. This is part of the "missing propeller drag" workaround. For (L/D)max see https://code7700.com/aero_l_over_d_max.htm

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 full weight, no flaps, retracted landing gear, full thrust, level flight, no elevator input and altitude 300 ft.

I use the MSFS 2020 documentation from https://docs.flightsimulator.com/html/Samples_And_Tutorials/Defining_A_Flight_Model.htm Citations are in "". Asobo has expanded the documentation, but sadly the documentation is still far away from complete. Asobo please go on!

To all critics of my work: First, I am an armchair pilot. If you only accept flight model mods from real life 4 stars pilots, don't use it. Second, if you think my mod is atrocious, don't use it. To everybody else: The mod is the best I can do with my knowledge of MSFS 2020. Stay happy and healthy!

empty_weight = 1455 ; 1291 ; Empty weight, (LBS)
cruise_speed = 219 ; 150 ; Knots True (KTAS)
Wikipedia technical data.

empty_weight_CG_position = 0.66, 0, 0 ; 0.85, 0, 0 ; Position of airplane empty weight CG relative to reference datum (FEET), z, x, y
Set GC to 28% MAC.

induced_drag_scalar = 1.5 ; 1
flap_induced_drag_scalar = 1.5 ; 1
For "missing propeller drag" workaround increase induced drag.

drag_coef_zero_lift = 0.0559 ; 0.02770
For "missing propeller drag" workaround increase parasitic drag.

lift_coef_flaps = 0.00000
drag_coef_flaps = 0.00000
For "missing propeller drag" workaround I can't use flaps nor gear.

ui_autonomy = 5 ; 4.5 ; max duration the aircraft can fly between take-off and landing in (Hrs)
fuel_flow_scalar = 0.63 ; 1 ; Fuel flow scalar
Adjust fuel_flow_scalar to ui_autonomy.

[PROPELLER]
thrust_scalar = 3 ; 1 ; Propeller thrust scalar
Adjust thrust_scalar to cruise_speed.

wing_dihedral = 2.8 ; 0.7 ; Dihedral angle Lambda (DEGREES)
Correct that left rudder brings down left wing.

wing_incidence = 1 ; Wing incidence (DEGREES)
htail_incidence = 0.6 ; 2 ; Horizontal tail incidence (DEGREES)
Set that for normal flight as much positive trim is needed as negative trim is needed for inverted flight at full thrust.

elevator_trim_neutral = 0 ; 4 ; Elevator trim max angle (absolute value) (DEGREES), for indicators only (no influence on flight model)
For my comfort.

empty_weight_pitch_MOI = 1826 ; Empty pitch moment of inertia, Jxx (SLUG SQ FEET)
empty_weight_roll_MOI = 68 ; 204 ; Empty roll moment of inertia, Jzz (SLUG SQ FEET)
empty_weight_yaw_MOI = 1817; Empty yaw moment of inertia, Jyy (SLUG SQ FEET)
This is "real" inertia. For better roll rate I decrease the roll value.

pitch_stability = 0.001 ; 0.1
roll_stability = 0.001 ; 0.1
yaw_stability = 0.001 ; 0.1
This is "fake" inertia. I switch off "fake" inertia.

aileron_area = 116.7 ; 16.0 ; Elevator area (SQUARE FEET)
For better roll rate increase aileron_area.

aileron_span_outboard = 0.99 ; 0.7
For better roll rate increase length of aileron as percentage of wing length.

aileron_effectiveness = 1 ; 2
For realism reduce "overshoot". The real world airplane performance is 400°/second roll rate. I set it to 220°/second. This is my compromise between performance and accuracy the current MSFS 2020 can handle.
With Aircraft Editor, Debug, Tracking you see Rotation Speed Roll.

aileron_up_limit = 30 ; Aileron max deflection  angle (DEGREES)
aileron_down_limit = 30 ; Aileron max deflection down angle (absolute value) (DEGREES)
Note: A higher value is too fast for the simulation and introduces too much "overshoot".

elevator_up_limit = 34 ; 26 ; Elevator max deflection up angle (DEGREES)
elevator_down_limit = 34 ; 26 ; Elevator max deflection down angle (absolute value) (DEGREES)
Increase elevator limit to give "nice" spin animation.

rudder_limit = 40 ; 30 ; Rudder max deflection angle (absolute value) (DEGREES)
Better slip and skid.

fuselage_length = 22.8 ; -1 ; Nose to tail (FEET)
fuselage_diameter = 3.55
fuselage_center_pos = -1.5, 0, 0.25
Having the correct fuselage_length helps in defineing a good fuselage_center_pos.

Summary: "If Asobo only knew what Asobo knows". Some Asobo engineers write documentation and tell everybody what to do and why. Other Asobo engineers write cfg files. As you can see above, these two groups don't talk to each other. Specially not about induced_drag_scalar and stability parameters.
Nowhere Asobo writes about the importance of (L/D)max (glide ratio) and how to set a proper (L/D)max. For me is a bad (L/D)max value the single most important reason for poor quality of (Asobo) flight models. Let's see what Asobo will do in the next software release!

Note from the author: Please upvote https://forums.flightsimulator.com/t/workaround-for-missing-propeller-drag-please/368300