The simulator looks fantastic but it is still lacks functionality and has some flaws which prevents it from being a realistic flight simulator. Although somewhat more true for the IFR pilots compared to the VFR pilots amongst us. Just as many others I’m also addicted to the nice visuals MSFS has to offer which makes it difficult to move back to other platforms. I just wished the rest of the sim was as big of a leap forward as the graphics.
Apart from the many positive effects of having such a broad audience, one drawback is that hardcore flight simmers with the experience and technical knowledge required to identify such bugs and flaws are no longer the majority. Important bugs / wishes required for accurate flight simulation are therefore not receiving sufficient attention and are not ending up in the “top bugs” or “top wishes”. I sincerely hope that in the end “no pilot will be left behind”.
I hope we can make a comprehensive list together of items in need of fixing for accurate flight simulation, engage in healthy discussion and make sure those items get the needed attention.
Inertia, Stalling, Pitch Authority and Sensitivity Flight Model Issues
Broken Stall Dynamics
It seems all aircraft are pitching up to CLmax and then just stay there for some reason. It doesn’t matter what aircraft, weight or configuration you test, aircraft pitch up to CLmax until running out of energy, even when stalling the aircraft transitions into a falling leaf instead of really making a clean stall break, drop a wing etc. Its almost like there is some AOA limiter installed limiting the AOA to just below stalling angle. During a climbing or descending turn the correct wing doesn’t stall. Aileron deflection also doesn’t seem to affect the local angle of attack and therefore its not possible to create a wing drop. It also seems impossible to pull any aircraft into an accelerated stall, even heavy aircraft transition into a vertical climb or loop instead of stalling (maybe connected the the lack of inertia below).
Lack of Inertia?
All MSFS aircraft are very responsive and “twitchy” on the controls, even heavier like the Airbus 320 and Boeing 748 are very hard to control in turbulence and gusts, being knocked from flight path instantly. In short it doesn’t feel there is much mass behind anything in MSFS, flying a heavy aircraft in gusts and turbulence feels like flying a light Cessna. It seems the lack of inertia is “solved” (masked is a better word) by changing the reactivity of the flight controls. The Boeing 747 feels heavy and sluggish, but this is actually caused by slow flight control movement. You can see this in cockpit view when moving the joke, the flight controls in the sim move very slowly.
Propeller Effects
Propeller effects like slipstream, P-factor, torque and gyroscopic effect are simulated according Asobo and just require further tweaking. As of World Update 3, the Cessna 172 still has no slipstream effect, unless you consider that one tiny hair to the right on the slip indicator slipstream. You can see after take-off there is no rudder required at all to fly coordinated. Also when cycling power between zero and full, close to stall speed there is no yaw at all:
In real life you would see the nose yawing all over the place when not correcting power increase / decrease with rudder input. In this video the rudder is not touched at any point. I did need to apply constant right rudder during take-off roll, so the right rudder, left rudder, back to right rudder issue during take-off roll seems to be fixed (no wind), at least on the Cessna 172. A comprehensive breakdown of each effect can be found below:
Propeller drag is a hot topic and despite Asobo claiming propeller drag is accurately simulated, drag is still completely absent on the three turboprops. On the Baron the drag is unrealistic, being able to fly below Vmca with a critical engine failure without losing control. On the Single Engine Piston aircraft it does seem to be accurate.
ATC System & Phraseology
The current ATC system is comprised of made-up phraseology and seems like a copy from FSX with the addition of departure and arrival routes. Other than that the overall functionality of the system has actually become worse. Discussion about ATC phraseology and ATC system in this thread:
I did change the ATC phraseology text-to-speech in the MSFS language file and released it as a mod:
Airbus A320 neo Lacking Climb Performance
The Airbus A320 is seriously lacking climb performance post world update - USA as can be found here:
Incorrect Flight Dynamics on Airliners
Flight dynamics for airliners in MSFS are fundamentally wrong with the Center of Pressure (lift) always being in front of the Center of Gravity (weight) and an up-force on the horizontal stabilizer. This causes wrong drag, fuel economy, flight behavior etc. Please vote this one up to raise awareness.
LDA / ILS Approaches
The bug which forces offset approaches to be aligned with the runway track is acknowledged by Asobo and apparently being worked on.
The problem causing RMI / bearing pointers to be able to point to LOC antennas was said to be fixed during last Q&A, but still seems to be broken:
Camera System
Even with camera movements set to OFF, the view is never 100% steady and the camera keeps moving in turns and turbulence. This is very annoying when flying and trying to scroll something into the flight guidance panel etc. whilst maneuvering or flying in turbulence, zooming in or out all of a sudden when the viewpoint shifts.
Switching between different view modes is a mess. Why do we need to switch to outside view first before being able to switch to fixed views or drone camera and vice versa? I have set up custom views to be able to quickly peak at something, I often need to select the key-binding for the appropriate custom view twice to get the correct orientation and zoom.
Why can’t the drone cam be made more intuitive. For example, the translation controls with arrows, WSAD or whatever (like you could set-up already right now) and orientation controlled with the mouse. It would be more intuitive to change orientation (pitch & yaw) with the mouse instead of keyboard assignments.
Turboprop Engine Model
More Information
Luckily this topic already raised sufficient awareness, some background information below:
Torque and ITT with changing altitude are wrong in MSFS. It works like this:
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With increasing altitude the air becomes less dense the drag on the internal engine components (compressor primarily) decreases with reducing density. The engine Fuel Control Unit maintains the selected engine speed for which less fuel is required. Result is: same engine RPM, lower ITT, lower torque.
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To compensate for the reduced torque the throttle lever(s) need to be moved forward, increasing the fuel flow. Torque is restored but the low air density (less cooling) combined with an increased fuel flow increases the ITT. At some point the ITT becomes more limiting than the torque and 100% torque cannot be achieved without exceeding the ITT limit.
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In MSFS the torque increases with increasing altitude and vice versa and the ITT limit is never reached not even at the aircraft ceiling.
The PT-6 is a free-turbine engine, this means that the compressor spool and the power spool (which drives the propeller) are in no way mechanically connected. This means that they can run at different RPMs without affecting each other.
In real life you could therefore feather the propeller and have the power-spool running at a very low speed without affecting the compressor spool. Unfortunately in MSFS the ITT spikes if you do this and gets hotter than the surface of the sun (well almost). This is behavior you would expect with a fixed shaft turboprop engine. There feathering the prop would cause the whole engine to spool down and the Fuel Control Unit (FCU) would increase fuel flow in an attempt to maintain engine speed resulting in high ITT.
I have flown the ATR 72 which is not powered by the PT-6 engine but its also a free turbine so the principles are the same. On the ATR we had a propeller brake which we could use to run the engine for electrical supply and airconditioning with the propeller stopped, like an APU. Feathering the prop on a free turbine engine on ground is completely normal and should not cause a high ITT.
Autopilot
The autopilot should disengage upon stall warning activation, manual trim activation etc. Also it should not be possible to control the aircraft while the autopilot is engaged, it is physically not possible to move the flight controls with the autopilot servos engaged. MSFS should disregard all manual control inputs whilst autopilot is engaged, up to the point sufficient control input is given to trip the autopilot offline.
The Vertical Speed (VS) function has wrong engagement logic.:
GPWS
For some reason, the GPWS mode 3 “don’t sink” alert is the only GPWS mode implemented, also it is often activating at incorrect times. Why is this the only implemented GPWS mode? Are the rest implemented but bugged and therefore not appearing in the sim? I believe even FSX had the basic GPWS modes implemented.
Meteorological Visibility / RVR
Currently it is not possible to simulate low visibility take-offs and landings since visibility can’t be accurately controlled and with 100% aerosol density will not drop below approximately 3000 m.
Wind Model
When selecting a ground wind in the weather menu, this wind is NOT actually the ground wind. The simulator uses the ground wind selected by the user as being the geostrophic wind at 1000 ft AGL and modifies it to make it the ground wind using some rough rule of thumb, cutting the windspeed at ground level in half. If you want to simulate a ground wind of 20 kts, gusting to 30 kts, you need to select 40 kts, gusting to 60 kts into the weather menu. This creates the problem that in order to simulate those gusty winds at ground level, you’ll need to select even gustier winds at altitude. In the real world it works the other way around, its normally getting more gusty while descending not less gusty…
Icing Effects
The problem is acknowledges by Asobo, now waiting for a fix and option to turn the icing effect OFF.
More Information
Icing effects are hard to predict in real life, icing conditions are pretty easy to predict, for icing we need three things:
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Visible moisture, can be clouds, visibility < 1600 m (1 statute mile), precipitation or taxiways / runways contaminated with water, slush, snow, ice etc.
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A Static Air Temperature below 5 degrees on ground or below 7 to 10 degrees Total Air Temperature in the air (depending on the aircraft type).
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The lack of freezing nuclei, this causes droplets to become “supercooled”, in this case they stay in liquid form although the temperature being below 0 degrees C.
The difference between TAT and SAT (the Ram Air Temperature or RAT) is caused by the “ramrise” due to forward motion of the aircraft and the resulting friction with the air. The ramrise can be approximated by the following formula:
(TAS / 100) squared
Slightly positive temperatures won’t protect against icing. This is because the airframe itself is still cold from cruise at higher altitude, due to cold fuel in the tanks (cold soaking) and because certain areas on the aircraft, primarily wings and engine inlets, lower the static pressure (for the engines only at low speed, before ram rise takes effect) with a resulting lower local temperature.
What kind of icing, rime ice, clear ice or frost depend on the relative humidity, the size of the droplets and the temperature of the droplets with the larger droplets causing rime and clear ice. It is hard to predict what the kind and severity of the icing conditions will be, even two clouds with the same conditions may vary.
Supercooled Large Droplets (SLD) is what causes severe icing conditions. They are primarily found in Cumulus and Nimbostratus type clouds. These severe icing conditions are rare, and the extend is usually not very large. In cumulus clouds the icing will be intermitted, so the horizontal extend is relatively small. In Nimbostratus clouds the horizontal extend can be large but the vertical extend usually isn’t. In other words, change of course, climb (if at all possible) or descent just a few 1000 ft are usually sufficient to escape.
The icing effects in MSFS are unrealistic in a couple of ways:
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The severity is too high. Almost every clouds immediately causes icing and at a extreme rate.
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In the real world ice builds-up only on the frontal surfaces of the aircraft, i.e. leading edges, nose, spinners and forward windshields. Not on the side of the fuselage or cockpit side windows.
I noticed on the TBM for example that the side windows freeze when selecting the windshield heat OFF, first off all I don’t thing those windows are heated in the first place, second those areas won’t pick-up any ice in the real world.
Pushback for GA Aircraft
https://forums.flightsimulator.com/t/pushback-for-ga-aircraft/328103?u=nijntje91
Black-out, Red-out & Hypoxia Effects
Weather Radar
The MSFS weather radar is currently useless as it seems to display clouds rather than precipitation. The problem is acknowledged by the developers and being worked on.
https://forums.flightsimulator.com/t/weather-radar-returns/333688?u=nijntje91
True Altitude vs Indicated Altitude
Temperature does not affect the indicated altitude vs true altitude in MSFS. The problem is acknowledged by Asobo and being worked on.
Every item above is reported via Zendesk but some extra attention in the form of votes for those topics is appreciated. Maybe we will see them fixed a little quicker.
If you think anything is missing, please drop it in the comments below!
Thanks!
