Introducing the Take Command! SR20 for X-Plane 11

Following the wonderful reception of the TorqueSim/RealSimGear Take Command! SR22 Series, we have been hard at work developing the Take Command! SR20 to complement it! This is not a simple modification: it is a product of thousands of hours of work, creating the highest quality rendition of the aircraft for X-Plane.

The X-Aviation Take Command! brand of products represents the very best of flight simulation immersion, and assures you this TorqueSim product is one of the most sophisticated, study sim level aircraft available for X-Plane! Real world pilots test and assist in the development of these products, and real world procedures are followed. It tells you these products are unlike any other product you’ve seen outside of the ever growing X-Aviation catalog! Want to feel like a real captain? Take Command!

While on the surface, the SR20 seems quite similar to the SR22, there is much more changed than what immediately meets the eye. We have worked to develop a fully custom engine model to implement the Continental IO-360-ES engine, with all its proper behaviors and quirks. With the systems, we had to go in and make the systems match a proper G3. The 3D model throughout is significantly revamped to match. This aircraft will be the perfect addition to any simmer’s hangar!

The Take Command! SR20 is designed to work perfectly with the RealSimGear G1000 and Cirrus Perspective Hardware. Learn more about the hardware options here!

The aircraft will be sold separately from the SR22 Series. A discounted upgrade price will be available to those who already own the SR22 Series by release day. As with the SR22 Series, this is for personal use only, contact us for information on commercial pricing. The SR20 will be available in just a few short weeks! For more updates and to be the first to hear about the release date, sign up for our email list!.

You can learn more about the Take Command! SR20 here.

As always, from the TorqueSim, RealSimGear, and X-Aviation teams, thank you!

Take Command! SR22 Series – 1.1 Update Feature Preview

Since the release of the Take Command! SR22 Series, we have been hard at work adding features, fixing bugs, and making general improvements throughout! We are preparing to enter a Public Beta in the coming days (if you are interested in being a part of the Public Beta, you can sign up for a spot hereNote: spots are limited), followed by a general release to everyone once it is ready!


Here are some of the key features we have implemented:

G1000 Terrain Profile Indicator

We have integrated a custom terrain profile indicator on the MFD. This will help for situational awareness, especially in mountainous terrain, and help prevent CFIT incidents. The custom system is entirely multi-threaded to prevent any performance penalty.

Visual Icing Effects

We have been hard at work adding custom visual icing effects to the aircraft! This will help with situational awareness surrounding the use of TKS during icing conditions, as the simulated ice can now be seen on the wing, inlets, windshield, spinner, and other relevant surfaces!

Engine and System Model Improvements

There have been many improvements made to the engine model and system model. Here are a few highlighted findings from our debugging and fixing:

SR22TN Power Fluctuations

There was an issue leading to potentially severe fluctuations of engine power during takeoff and climb at high ambient temperatures and altitudes, on the SR22TN only. The cause of this issue has been eliminated. However, there may still be minor residual fluctuations on takeoff and initial climb under such conditions, largely attributed to mixture being slightly too rich for such higher density altitude takeoffs. It can be further amplified by too quick movements of the power lever. To get rid of any remaining fluctuations altogether, embrace the following steps when setting takeoff power at high temperatures and/or density altitudes:

  1. Advance power slowly until the point where RPM rises above 2500 RPM (around 80% lever travel) and wait for manifold pressure to stabilize. This will take a few moments at altitude and is particularly important up there.
  2. Start your takeoff roll and simultaneously advance power slowly to maximum.
  3. Procedures allow you to lean the mixture to 34GPH for takeoff on hot days. It is suggested to follow this step at OATs in excess of 30-35°C to eliminate any residual power fluctuations.
  4. Advance the mixture to full rich after obstacles are cleared.
    Also keep in mind that it is normal for the turbo-normalized engine to slightly fluctuate for a few moments after power changes before all parameters stabilize. Thus it is generally recommended to make power changes slowly on such engines, so even during go-arounds better take 2-3 seconds to advance to full power.

Random engine cutout during taxi

There was an issue leading to seemingly random engine quits during taxi. A fix is in place that has proven to work in internal tests.

Engine starting

The fuel-injected IO-550 engine can be challenging to start at times, so video tutorials to prepare you for all kinds of cold, hot and flooded starts you may face. We have also seen the most typical cause relates to mispositioning the power lever for engine starting (some even at maximum), keep in mind to set the lever to about 1/4” (i.e. at or slightly above the letter R in POWER). We have determined that there is no issue with the custom engine model.

Engine cutout after landing

When landing at higher density altitudes with the power lever at idle on rollout, it is to be expected that the engine may not be able to hold its idle RPM due to an excessively rich mixture. Lean the mixture to the appropriate X-T letters in MIXTURE immediately after landing and try to keep the power slightly higher than low idle to prevent the engine from quitting in such situations. We have determined that there is no issue with the custom engine model.

Take Command! SR22 Series Update 1.0.1

This will serve as a formal announcement that we have released the version 1.0.1 update for the SR22 Series. All customers who have purchased the SR22 Series up till now have been sent an e-mail by X-Aviation with complete instructions on how to obtain your update. We have made this a very simple process! For those that purchase the SR22 Series from today forward, your purchased download will already be updated to version 1.0.1 for you.

With this update, we have made major enhancements to the aircraft all around and fixed a wide assortment of bugs. We have resolved the most significant of issues, including the CTD some users experienced when loading and/or activating the aircraft, and some incompatibilities with other plugins.

As always, we are working away on ensuring the best X-Plane experience! Make sure to report any issues you may encounter so we can get to fixing them ASAP.

What if I didn’t get the update e-mail?

If you did not receive your update e-mail don’t fret! X-Aviation has updated our system to allow all customers to update with ease, regardless of whether you received an e-mail for the update! Here’s what to do:

1. Login to your X-Aviation account here: https://www.x-aviation.com/catalog/account_history.php

2. Find your original SR22 Series download and re-download the file. It will download as the latest version!

The following is a list of additions/fixes included:

Improvements / New Features:

  • [SR22-376] – Resolve the CTD and inter-plugin incompatibility bugs
  • [SR22-337] – FS Economy support (ability to disable custom load manager to use default)
  • [SR22-348] – Show load readout in gallons on load manager
  • [SR22-353] – Allow weight configuration for pax and baggage in the load manager
  • [SR22-354] – Simulate door closing with airflow over aircraft (airspeed, rpm, spiraling slipstream, temperature, air density, and more all are part of this simulation!)
  • [SR22-20] – FMOD Improvements and Modifications
  • [SR22-150] – Improved VR Config file

Bug Fixes:

  • [SR22-338] – YD could be on at cold/dark
  • [SR22-340] – G1000 Checklist Cruise climb airspeed too high on SR22 Normally Aspirated
  • [SR22-350] – Glass reflectivity persistence
  • [SR22-351] – Add support for the main “-” character in the livery editor
  • [SR22-352] – Oil temp could be frozen by fast power lever movements
  • [SR22-357] – Airframe replace button now also fixes all X-Plane failures
  • [SR22-362] – PFD buttons didn’t work when MFD is off
  • [SR22-363] – Flap animation could cause issues in replay mode
  • [SR22-368] – CHT caution stayed on when back in green range
  • [SR22-377] – Oxygen system refill logic improved
  • [SR22-342] – Milkshake visibility persists between loads
  • [SR22-344] – Engine less prone for flooding, faster flooded start
  • [SR22-369] – Higher EGT increase on single magneto
  • [SR22-373] – Improve RSG Popup functionality with older RSG plugins
  • [SR22-29] – Improve interior lighting
  • [SR22-54] – New 3D pilots and pax
  • [SR22-367] – Animate GCU knobs
  • [SR22-78] – Flap animation axis fixed
  • [SR22-208] – Engine sound not depending of engine combustion
  • [SR22-285] – Paint Kit (Available on X-Pilot Forums for Download)
  • [SR22-320] – Alt static source selector doesn’t move
  • [SR22-336] – External lighting bugs
  • [SR22-339] – Side stick AP Disconnect Command was incorrect
  • [SR22-356] – Ice light turns no longer turns off with landing light
  • [SR22-358] – SR22 Electronic trim sound doesn’t shut off after using trim.
  • [SR22-359] – Key animation fixed
  • [SR22-360] – External sound depends on door
  • [SR22-364] – PFD mislabeled knob
  • [SR22-245] – FMOD Physics Connection
  • [SR22-349] – Rotating GCU knobs
  • [SR22-365] – G1000 Pixel Effect Visibility
  • [SR22-366] – Commands for Exterior Items

As always, thanks for being a customer with X-Aviation. We appreciate your feedback and support!

Take Command! SR22 Series has arrived!

TorqueSim, X-Aviation, and RealSimGear are excited to announce the Take Command! SR22 Series has arrived and is ready to join your hangar! Don’t be fooled by imitations. THIS is the SR22 flight schools will be using! The Take Command!: SR22 Series includes both Normally Aspirated and Turbo SR22 G3 variants in one package. The systems simulation along with 3D modeling is incredible. There’s no other SR22 on the sim market like it.

Highlighted Features

  • Fully Custom IO-550 Engine Simulation. Cylinder detonation, spark plug fouling, improper magneto grounding, and more. SR22TN adds the Tornado Alley Turbonormalizing system. All components are modeled from real data with complex inter-component interaction. 
  • Detailed electrical system. Simulation of all buses, circuit breakers, Master Control Unit, both Alternators, and both lead-acid batteries. Inter-system interaction is simulated so loads on the electrical system can affect engine performance. 
  • High-Fidelity Flight Model designed for unparalleled accuracy. Custom airfoils, stall strips, cuffed wings, and accurate control surface deflections are all modeled.
  • Maintenance and Failure Model. Excessive wear will affect airframe performance and safety, addressed through a realistic concept of runtime-based and annual inspections. This also includes truly unique features like cylinder detonation driven by the physics engine. TKS fluid panels drain over time in warm conditions and need to be primed, tires flatten, brakes fade when hot, the propeller experiences FOD on unprepared surfaces and much more to discover. Probability distributions tuned with real-world data are used to reflect the increasing likelihood of failures with component runtime. 
  • Custom TKS Ice Protection System (FIKI), with full system logic control in all normal and backup modes. Fluid metering pump model down to pump speeds and pressures, correct timing of pump operation cycles, pump speeds and flows depend on system voltage. Clogged filters provokes higher pump pressure and lower fluid flow. 
  • Custom Fuel System with Vapor Lock simulation. Main and Collector Tank are modeled, fuel sloshes depending on sideslip angle, affecting float-sensed quantity and strainer coverage. Every component in the fuel delivery path is simulated and contributes to the overall system behavior. Hot fuel can cause vapor formation and power fluctuations at high altitude in flight, suppressed by use of the boost pump 
  • Oxygen system where flow rate and oxygenation are controlled via a custom oxygen flowmeter. Oxygen tank temperature causes difference between sensed and actual pressure, oxygen flow rate depends on number of passengers on board. 
  • Persistent State – when you shut down the aircraft, you will return to it in the state in which it was left, the engine components will take their real time to cool. This encourages the proper care and handling of the aircraft, and shows the consequences of reckless flying. 
  • X-Plane 11 G1000 avionics with additional customizations including engine pages, synthetic vision, lean-assist functionality, CAS simulation, and checklists. All these customizations are designed to also work perfectly with the RealSimGear G1000 and Perspective Package. 
  • Integrated Synthetic Vision into the PFD with obstacle display, navigation pathways, and airport labels.
  • Meticulously detailed 3D model, with full 4K PBR textures and the wide variety of materials accurately replicated. 
  • The FMOD sound pack has been the result of hundreds of hours of source audio, carefully recorded from the real aircraft. Recordings of the engine on the ground, and in-flight have provided for a highly-accurate and immersive sound pack replicating the real aircraft. Every switch, knob, lever, and button have been modeled. 
  • The tail number can be dynamically changed on the aircraft! There are many configuration options to make the plane yours – from changing the tail number color, placement, outlines, drop shadows, including adding it to the wings as well!
  • Heavily multi-threaded systems architecture to leverage performance of modern CPUs with many cores. 
  • Full aircraft state persistence. Every switch, flight control position, fuel state and on-airport position is restored upon reload. Even between reloads, system resources change in real time. The engine and oil cools down slowly between flights, the battery drains, tires slowly deflate, etc.
Image Credit: @SilentDark666 via Discord

Take Command! TorqueSim SR22 Series Releasing Next Week!

TorqueSim, RealSimGear, and X-Aviation are excited to announce the SR22 Series for X-Plane will release next week! The SR22 series is the cumulation of thousands of hours of work, creating the highest quality rendition of a piston aircraft for X-Plane to date: everything is simulated! Both the SR22 G3 and SR22TN G3 are included.

To make sure you know when it releases, you can sign up to hear first here!

We will be providing copies of the aircraft to streamers and other content creators to get you a first look!


The TorqueSim SR22 Series is part of X-Aviation’s “Take Command!” series of products. The X-Aviation Take Command! brand of products represents the very best of flight simulation immersion, and assures you this TorqueSim product will be one of the most sophisticated, study sim level aircraft available for X-Plane! Real world pilots test and assist in the development of these products, and real world procedures are followed. It tells you these products are unlike any other product you’ve seen outside of the ever growing X-Aviation catalog! Want to feel like a real captain? Take Command!


Main Features:

3D Model and Sounds

The TorqueSim SR22 and SR22TN have been meticulously detailed to provide for the most in-depth visual model for the SR22 possible. The aircraft makes full use of 4K PBR textures, ensuring the highest level of visual fidelity. All the different materials are accurately represented from samples from the actual aircraft!

The FMOD sound pack has been the result of hundreds of hours of source audio, carefully recorded from the real aircraft. Recordings of the engine on the ground, and in-flight have provided for a highly-accurate and immersive sound pack replicating the real aircraft. Every switch, knob, lever, and button have been modeled in the sound-pack. 

Engine Model

Both the SR22 G3 and SR22TN G3 are simulated. The SR22 is equipped with a normally aspirated Continental IO-550-N capable of 310 HP, while the SR22TN models the Tornado Alley turbo normalizing system attached to the engine. The TorqueSim custom physics model is the most accurate simulation of a piston engine for X-Plane! The simulation models the mass flows of air and fuel through every part of the engine in real time. Air enters the engine through the air filter, flows through ducts, passes obstacles like the throttle plate, burns the fuel and leaves the engine as exhaust gas. Pressures and temperatures are calculated in every section independently, all contributing to the different segments of the simulation. With the Tornado Alley turbo-normalizing system installed, the full performance capability of the engine model comes into play, as compressors, intercoolers, wastegate and turbines also have their places in the calculation of air flows and pressures. All engine parameters are tuned against a huge database of real engine log data to ensure maximum possible accuracy in all phases of flight. The entire engine simulation runs on a separate thread from the main simulator. This allows for the timing necessary for proper simulation, independent of sim frame-rate, but also ensures that the model has a near-zero performance impact on the simulator!

G1000 Perspective

Significant work has gone into enhancing the Laminar G1000 to provide many of the functionalities in the G1000 Perspective suite. Synthetic Vision, as implemented in HotStart’s TBM900 and TorqueSim’s Pocket Rocket has been integrated. The engine pages and sidebar have been modeled fully to provide the necessary details for proper engine management. Lean-assist functionality has been integrating assisting in the proper leaning of the engine. Checklists have also been integrated onto the G1000 providing easy access to the necessary preflight, starting, in-flight, post-flight, and emergency procedures. In addition to these additions, numerous other tweaks were implemented including matching the Perspective’s Top-Bar details including % Power, and destination calculations, in addition to the integration of “Know your Limits” and the fuel calculator system (which we implemented as a custom interface for refueling the aircraft!). All these customizations are designed to also work perfectly with the RealSimGear G1000 and Perspective Package. 

Electrical System

The SR22 electrical system has also been intricately detailed, ensuring every last breaker and switch is modeled. The dual-batteries are simulated with a custom lead-acid battery simulation. The dual-alternator setup and Master Control Unit have been intricately tuned to interface with the rest of the simulation. All 11 electrical busses and 48 circuit breakers are individually simulated to provide for the most in-depth of simulation. 

Fuel, Oxygen, and TKS Systems

The SR22 fuel, oxygen, and TKS systems have all been custom simulated, providing for unparalleled accuracy in-flight. The fuel system models all the details down to the fuel lines and injector nozzles! Fuel temperature is calculated and vapor is formed in the lines under the right environmental circumstances. This also allows for the recreation of all engine starting characteristics usually found on an aviation piston engine like normal, cold, hot, flooded and false starts. So be sure to understand the importance of your boost pump both on ground and in flight! The complex behavior of the engine driven and electric fuel pumps as well as the fuel manifold and metering unit are simulated. Changing bank and attitude of the aircraft affect sloshing in the tank, thus causing the indicated fuel quantity to differ. The TKS system models the multiple operational modes through the independent simulation of tanks, pumps, and fluid lines. The oxygen system is no slouch either – the tank, along with a configurable flowmeter are integrated to provide for an excellent platform for high-altitude operations. The simulator‘s hypoxia simulation is modulated to reflect real time of useful consciousness depending on oxygen flow, so make sure to configure the flowmeter properly!

Maintenance and Failure Model

The SR22 also features an engaging and beneficial maintenance, wear, and failure model. This aspect of the simulation makes sure that the plane is flown safely and without damage. Excessive wear will be affecting airframe performance and safety, addressed through a realistic concept of runtime-based and annual inspections. The entire wear and failures logic is built on top of the physics model for engine, airframe, fuel, TKS and oxygen systems. This also includes truly unique features like cylinder detonation driven by the physics engine. TKS fluid panels drain over time in warm conditions and need to be primed, tires flatten, brakes fade when hot, the propeller experiences FOD on unprepared surfaces and much more to discover. Probability distributions tuned with real-world data are used to reflect the increasing likelihood of failures with component runtime.

High-Fidelity Flight Model

The flight model is designed with unparalleled accuracy. The tuning of the aerodynamic profile required hundreds of hours of careful tuning to accurately match the real-world characteristics. The base model was created by X-Aerodynamics, and further built upon to match the aerodynamic quirks of the real aircraft to the limit of the simulator! 

Persistent and Performance Tuned

The countless systems are all designed with persistence in mind – when you shut down the aircraft, you will return to it in the state in which it was left, the engine components will take their real times to cool. This encourages the proper care and handling of the aircraft, and shows the consequences of reckless flying. These systems are also designed to run on computers of many different specs. All the systems are programmed in C/C++ using the X-Plane SDK. No compromises were made for simplicity. The plugins make significant use of multithreading to have the absolute minimum processes running on the main simulator thread, thus helping keep X-Plane performance at its maximum!


We highly recommend looking at the TorqueSim website for more details and to see our series of development updates, which can be found at torques.im/sr22.

Make sure to join our newsletter to stay up to date, you can sign up to hear first here!

SR22 Development Update 6

We are excited to share what we have been working on behind the scenes for the last month and a half! We last shared about how we are integrating the many unique aerodynamic features of the SR22 into the model, this has been further refined along with our custom engine model (which was discussed here). While refining our custom systems has been a top priority for the development team, our 3D artist Steaven has also been hard at work, making one of the best 3D models for an X-Plane aircraft to-date!

RealSimGear Integration

Our rendition of the SR22 aircraft has designed from the onset with the hardware customer in-mind. Our aircraft will integrate perfectly with the RealSimGear Perspective Hardware, providing the ideal home flight simulator.

The RealSimGear Cirrus Perspective hardware package will work out of the box with the new aircraft providing a fully integrated and easy to configure home training solution for people wanting to learn and practice flying real Cirrus aircraft. The PFD and MFD screens will automatically display the screen contents when the aircraft is loaded, all buttons and knobs will be pre-configured. This makes it possible to practice the exact same workflows and procedures you would normally encounter during a real world flight, including full checklist operation, flight plan loading and instrument approaches. This coupled with the extremely realistic engine and system modeling means that flying with the simulated aircraft combined with realistic hardware provides an incredibly effective home training platform.

Learn more about the RealSimGear G1000 + Cirrus Perspective Package here.

3D Modeling and Texturing Update

We have also nearly completed the 3D model and texturing process for the aircraft! The model has full 4K PBR texturing, with accurately replicated materials throughout (Even down to the style of fabrics and leathers used)!

Engine Model Update

The SR22 IO-550-N engine will be the most accurately replicated piston engine for X-Plane. The engine is simulated down to each individual component! Over the past few weeks, the engine model has been further refined and extensively enhanced in order to represent the proper behaviors of the IO-550-N as authentically as possible during normal, hot, cold, flooded and false starts. This is now supplemented by an extensive oil system and other features never seen before on piston engines in X-Plane, such as engine knock (detonation) based on real data as well as some unique characteristics pointed out by real Cirrus pilots on our testing team. The entire component-based simulation of engine, fuel, TKS and oxygen systems has also been integrated into a novel maintenance concept which organizes maintenance intuitively in the form of inspections.

Our custom FMOD sound pack also benefits from the advanced physics-based system simulation. For example, when flooding the engine you will hear fuel dripping from the cylinder drain port. On the SR22TN you will hear the sounds of the turbochargers depending on their speeds.

Electrical System Update

We originally discussed the Electrical System back in February, detailing the level of depth of the system. We have further refined, tested, and validated the system in all of its various modes! We have developed an internal physics model simulating the lead-acid battery and its various behaviors. The behaviors of the Alternators and the Master Control Unit are also all simulated. The electrical system is a low-level physics simulation, when a switch is flipped on the plane, instead of simply checking for power on the bus, the SR22 simulation actually connects the “switch” tying the individual electrical item onto the power bus. This new logic allows for the many different states of the SR22 to be dynamically simulated at runtime.

New Website!

TorqueSim has a new website! Visit torquesim.com to check it out, our goal was to make everything easier to find and for the website to load quickly across the globe. We have split off the development blog from the main website, you can now find our development blog at blog.torquesim.com with our update blog posts and more.



SR22 Development Update 5

Aerodynamics is one of many reasons why we all love X-Plane. That’s also why, just like with the engine, aerodynamics on the TorqueSim SR22 have been designed to take full advantage of the simulator’s capabilities and get as close as possible to the real world equivalent. Therefore a professional flight model of the SR22 was created by X-Aerodynamics in 2018 – over many months of work using all available resources and documents. It is up to the most recent standards and greatly benefits of the flight model improvements introduced with version 11.41 of the simulator and is ready for 11.50.

Key features

  • Highly accurate cruise speeds and rates of climb
  • Precise matching of stall speeds and glide ratio
  • Correct take-off and landing distances
  • Spot-on shape of the aircraft body to supply the most accurate input for X-Plane´s flight model effects
  • Accurate control surface areas and deflections for realistic turn rates

Special features

A stack of custom airfoils ships with the flight model to resemble the scimitar-shaped propeller as well as the Roncz wing profile introduced with G3 of the SR22 which has some interesting characteristics:

Cuffed Wing Design

This term refers to the non-continuous leading edge with its characteristic droop on about the outboard half. Thus the outboard section features a lower angle of incidence than the inboard section and is still flying while the inboard part is already stalled.

Stall Strips

The real wing offers stall strips to complete the cuff effect, and our airfoil polars contain modifications in the places where these are located to accurately account for their effect. Stall strips are small attachments mounted at the leading edge located on the wing´s root, triangular in shape. At high angles of attack, they trip the laminar boundary layer at a location where stall is most favorable to onset, causing earlier flow separation and consequently a sooner stall than on the outer wing portions.

Together with the cuffed wing design, the SR22 wing is engineered to stall from inboard to outboard, allowing for maximum roll control and spin prevention way into the stall.

SR22 Development Update 4

COVID-19 Status:

We would like to take a moment to share our well wishes to everyone during this unprecedented COVID-19 pandemic. Currently, all members of our team are healthy, and as we work remotely already, work is progressing normally. As always, safety and health remain paramount to us.

Best wishes,

Steaven McKenzie and Cooper LeComp

Managing Partners, TorqueSim Aircraft Development

The TorqueSim Pocket Rocket is on the final day of its sale (45% off), returning to normal pricing on Sunday, March 22 at midnight eastern time. If you want a fun aircraft to add to your fleet when you are stuck at home, we’ve got you covered! You can get it here.

A fully custom engine model:

Enhanced or custom engine and failure models are becoming increasingly established in flight simulation, but are usually not able to trace the characteristics, peculiarities and limits of an aviation internal combustion engine back to a well-founded model, because there is a lack of physical basis and often simple, schematic relationships are used. Unfortunately, this often leads to confusion and resentment even among real pilots, including myself.

Our SR22 and SR22TN will therefore be the first aircraft to be equipped with a technology I have been working on for the past two years which is fundamentally new in X-Plane – as the aircraft nears completion, I have the honor of introducing you to the results of this work in the coming weeks, which will also cover flight model, TKS and oxygen systems, but this week we will start with the engine – the Continental IO-550-N, delivering 310 hp at 2,700 RPM.

Why go beyond X-Plane’s engine model at all?

X-Plane’s piston engine model is great in being generic and it provides a good approximation of all relevant performance parameters for a wide range of different engines. However, at its core it is configured by only a handful of parameters and can therefore be quite unprecise in individual cases, sometimes large discrepancies in the combinations of power parameters can be found and the power curve does not fit every concrete model. It also does not reflect the dynamics and inertia of an internal combustion engine very well, and those of turbochargers practically not at all.

Based on scientific literature, I have succeeded in integrating an approach to simulate an aircraft piston engine in X-Plane, which maps the mass flows of air and fuel in each part of the engine in real time. Air enters through the air filter, flows through ducts, passes obstacles like the throttle plate, burns the fuel and leaves the engine as exhaust gas. Pressures and temperatures are calculated in each section, the system is modular and can map even complex induction systems like the one on the SR22TN. With the Tornado Alley turbo-normalizing system installed, the full performance capability of the engine model comes into play, as compressors, intercoolers, wastegate and turbines also have their places in the calculation of air flows and pressures.

The output is not simply made to fit, it requires many real input parameters such as the shape of the throttle plate or ducts or a turbocharger map for the TN, all of which have been carefully researched and integrated in months of work – but everything else just falls into place, finely tuned to match the documentation of the real aircraft within a few percent across the entire normal flight envelope. We have made no compromises here! Also regarding your framerate, the architecture is heavily multithreaded and has virtually no performance impact on X-Plane.

Does it have other advantages as well?

The biggest advantage of this approach is the fact that the masses of air and fuel are available at hand and therefore the air-fuel ratio in each individual cylinder. So it is known at all times whether fuel is able to burn at all and how efficiently. You will notice this when priming and starting, when flooding the engine or when leaning – the EGT of the cylinder with the first peak will decrease while all others are still increasing!

You will even have the possibility to turn some engine set screws which a mechanic in reality also has to adjust for example maximum fuel flow or manifold pressure target on the turbo-normalized.

Inertia and dynamics are directly visible in the evolutions of fuel flow and manifold pressure when moving the power lever, especially in the TN. Turbocharger speeds are calculated and they need time to accelerate – just like the wastegate does to compensate for you advancing that power a bit to quickly on takeoff and the resulting overboost by allowing parts of the exhaust to bypass the turbine!

The fuel system has been treated in the same way as the air system, from tanks to the injector nozzles. You will notice fuel sensors and strainers that are sensitive to bank. Fuel lines which take time to empty and fill, engine-driven and boost pumps with fuel pressures following real evolutions.

Since the model simulates the engine down to its smallest components, it offers the optimal conditions for a very fine wear and failure system. Just imagine, on a hot day with warm fuel, to quickly climb up to the flight levels and forget about the boost pump – vapor lock will certainly be waiting for you! Or think of an induction system leakage at FL250 which makes you lose all your manifold pressure, followed by a steep descent cooling down the engine and wearing out the cylinders – but thankfully the SR22’s propeller control is connected to the throttle lever, which limits engine speed to 1,900 RPM at low power settings.

There are so many more advantages to this you will still be able to discover yourself.

SR22 Development Update 3

It has been a few weeks since the last update and we are excited to share all the progress we have made!

First off, we now have the SR22 3D model integrated and flying in-sim! This is a huge milestone for us, as this means we will soon be entering our closed beta stage. 

We are also excited to announce that another developer has joined our team, Marius Bohn! Marius has been working on an engine model for the IO-550 for over a year, and we are in the process of integrating the custom engine model, custom oxygen system, custom anti-ice system, and more.

We have put together a preview of our current progress on the FMOD sound pack here:

SR22 Development Update 2

It has been another week of work on the SR22!

This week, we will show previews of the interior and demonstrate the many features of the electrical system that is being simulated, even beyond the individual circuit breakers.

Interior Previews

Electrical System

The electrical system is complex, but important to be accurate. We have simulated many different aspects of the system:

  • Electrical Sources
    • Battery 1 and 2
    • Alternator 1 and 2
  • Electrical Distribution Busses
    • Main Distribution Bus 1/2
    • Essential Distribution Bus
  • Electrical Busses
    • Main Bus 1/2/3
    • Avionics Bus
    • Essential Bus 1/2
    • Non-Essential Bus
    • A/C Bus 1/2

With the accurate representation of these many different busses (and associated circuit breakers), we can ensure a proper simulation of the avionics/systems in all the many different potential configurations imposed by mismanagement or failures – providing a robust platform to train upon.

Here is a diagram we are using in the system’s development, where the connections between distribution busses and general busses are shown in different colors.