In 2016 we began the very ambitious project of writing our own avionics stack for the Cirrus Perspective from scratch. This project was started even before G6 was released with the Perspective+ upgrade. We found out quickly that there is no manual or online resource to describe how an avionics FMS operates; that information lives in the minds of those professionals who have traveled the road before and accumulated the needed tribal knowledge.
We released our first version of software in 2020, and despite some limitations, it was well received overall and allowed us to meet the requirements for AATD and BATD approval. We quickly realized however that the base architecture and technology stack that was selected in 2016 was no longer able to keep up with with our clients' growing needs. Because of this, in early 2023 we made the difficult (but necessary) decision to completely restructure and redesign our software with the help of a much larger team and under the leadership of an individual who has already built not 1 but 2 full stack avionics products in the past.
Our primary goal with NFS V2.0 was to accurately simulate the complex intercommunication of the Perspective+ system architecture. In our airplanes, each LRU plays a very specific role and communicates with the system as a whole in a specific way. By breaking each line replaceable unit (LRU) into a discrete virtual computer that communicates within the network using the same pathways as the real aircraft, we are able to very accurately replicate LRU system failure modes that occur in the sim the same way they would occur in the airplane. No need to "simulate" a failure, they occur intrinsically.
We have all seen this block diagram during our training and most of us probably went a bit cross-eyed and turned the page. This diagram, however is the heart of our Perspective+ avionics anatomy and dictates how everything behaves as a whole.
The first thing users will notice when launching NFS V2.0 software is the main LRU flight control management page. Look familiar?? Using this page, each LRU is modeled as its own virtual unit that can be powered on, off or failed with ease from the instructor station. These LRUs communicate via internal LAN network, much the same way as the ARNC 429 protocol communication in the airplane.
We cannot express how thankful we are for our customer base for being patient as we work through this major software overhaul. We will be using this page as a means of communication to keep current and future customers updated and excited about all the great work we are doing for our wonderful Cirrus community!
UPDATE 6/30/23- virtual LRU networking libraries built and communicating
The first step for our new software architecture was to build each LRU as its own virtual component and then network them all together over LAN. We now have all LRUs communicating efficiently with little CPU burden.
UPDATE 9/30/23 - graphically modeled hardware completed
Although the software will be controlled by physical hardware, all hardware components have been graphically modeled in NFS 2.0 to create a more robust and complete product offering. This will also allow customers to take advantage of hardware components that they may not physically have, such as the circuit breaker panel. The physical hardware communicates with its graphical counterpart using industry standard CAN communication protocols, the same method used in industrial equipment and automobiles.
UPDATE 11/15/23 - COM, NAV, Surveillance
We have completed our CNS functionality so that a basic IFR flight can be accomplished by flying land based navigational aids on green needles (VOR, LOC, ILS). Both the CDI and VDI indicators have been optimized to improve refresh rate to provide fluid needle movements. We have also reworked the back end data structure to significantly improve refresh rate of the PFD attitude information so that there is no visual "ticking" between refreshes.
UPDATE 12/30/23 - FMS flight plan entry
changing our code base did not only include the underlying LRU architecture. We also changed the code structure to allow a more accurate way of modifying the FMS flight plan. We have now completed the communication between the front end LRU and backend GIA flight data computers so that flight plan entries and modifications are indexed and sequenced properly. For all procedures and database items, we are no longer using the free FAA data and have implemented the Jeppesen database for accurate and worldwide coverage.
We have now also implemented the dashed Quick Select box so that the FMS can be navigated using the GCU range joystick.
UPDATE: 1/15/24 - Topography mapping
One of the biggest deficiencies of our NFS V1.0 software was the lack of beautiful color map that Garmin systems are so well known for. Not only have we completed our standard topography, but we also have completed our relative topography. Having control of our own high resolution topo map that does not reply on pulling data from XPlane cannot be understated and marks a major milestone for the project!
3/25/24 - Jeppesen data
We have completed our ARNC424 software parser so that we are now able to implement the full Jeppesen database including charts into our MFD. For customers who wish to have a subscription for in cockpit charts, we will also have access to the worldwide Jepp charts library. This database gives us all of the data including:
Airports
Airways (high and low)
Airspaces
MOAs
Waypoints
Procedures
Charts
etc.
Being able to license the Jeppesen database to our customers without needing to rely on a well known 3rd party data provider (who is not authorized to sell data to commercial-use customers) was a critical step.
4/5/24 - NEXRAD Radar overlay
One component of simulator flying that is very difficult to replicate is that of weather flying. In the cockpit, we have many tools available to us through our XM weather services to help avoid and mitigate weather related hazards. Our software is now able to generate NEXRAD radar data based on the sim environment and paint it on the MFD to show precipitation cells the same as you would see in the cockpit!
4/16/24 - GTC580 UI Screens
During the CPPP event in Knoxville, TN, we had a chance to evaluate the avionics hot bench for the G7 aircraft. These UI screens are the result of being able to interact with the actual hardware. Not only are the screens created, the underlying software transitions and features are being connected to our existing LRU structure.
CURRENT DEVELOPMENT EFFORT
Back end: FMS flight plan calculations, AFCS
Front end: drawing leg type segments (solid white/magenta, GPS steering course, future GPS steering course, etc.), GTC580 UI for SF50 and G7 SR