Story ID: 040
Avilution’s XFS Software Achieves First FAA Approval
By: Matt Thurber
Caption: Product is a replacement for unreliable Eclipse 500 air data computers
Word Count: 1294
An Eclipse 500 very light jet is now flying with an upgraded air data computer (ADC) developed by Resurgent Aviation Solutions and using Avilution’s eXtensible Flight System (XFS) software. This is the first FAA-approved use of XFS, according to Avilution, and offers “an efficient solution for upgrading older aircraft like the Eclipse 500 to meet modern standards.”
Integration of hardware components into the ADC upgrade was done by Skytron Avionics, and this work will help keep Eclipse 500s flying with a modern ADC solution.
“A big advantage of this outcome was that nothing changed with the pilots’ interface to the avionics,” said Avilution founder Mark Spencer. “This integration is completely invisible to the flight crew, avoiding the need for additional flight training or procedure changes.”
Based at Huntsville International Airport in Alabama, Avilution develops avionics software that can run on a variety of hardware, eliminating the dependency on proprietary software and hardware that is typical in the avionics industry.
“We are approaching avionics as the software product it has become and trying to address that in a way that takes advantage of the technological advances in the rest of the computer world,” Spencer explained. It doesn’t make sense to carry around a separate flashlight, camera, and text messaging device when all those functions are just software on a highly portable smartphone.
In aviation, he added, the flight management system is “just another box, and so is an autopilot, but the bulk of these are software applications.” What Avilution is doing is making it possible to create avionics products that are software-based and not stuck inside proprietary hardware, he said, “while recognizing the unique challenges of safety that are so important in the aviation sector.”
This work is underway not just in the general aviation arena but also for military and space products. The U.S. Army calls this the modular open systems approach, Spencer said, “and has been talking about this for a long time. Imagine a world where hardware is separate from software. If you like a Dynon primary flight display but want ForeFlight as the moving map, imagine those in your systems. With appropriate modularity, we can incorporate these components into an integrated system that is not currently supported. [Now] if you want to play in the Garmin sandbox, you can only play with their toys.”
Avilution is trying to make it possible for aircraft manufacturers to buy the underlying hardware and run the desired avionics as software, not unlike buying a personal computer that can run almost any software product.
Work that Avilution is doing includes integrating components such as radio and attitude and heading reference systems using a common format to support data transfer, all aiming to meet the highest design assurance level (DAL) required by regulators. One example is Avilution’s software running on the latest Collins Aerospace operating system. Avilution also ran a demo for the U.S. Army where it installed software on a legacy Sikorsky Black Hawk helicopter equipped with a next-generation avionics suite.
To simplify the process, Avilution’s software is highly configurable, Spencer explained. “It’s just like how Microsoft’s Excel works. It has a number of formulas that you use to create a spreadsheet that ties them together to solve problems. We don’t have to implement every requirement; we just implement the design pattern and use a configuration to map requirements into the software.”
In the case of the Black Hawk demo, during the exercise, Avilution was asked to implement two new requirements that hadn’t previously been specified. “We were able to implement this in the field without having to change the operational flight program of the aircraft,” he said, “by making changes to those configuration files used to map the behaviors and control two other parts of the radio that we had not been asked to before.”
The ADC for the Eclipse 500 is one of three and has a high failure rate, according to Spencer. Resurgent Aviation Solutions was able to source a replacement but needed it to act like the original ADC to simplify the upgrade.
Another interesting aspect of this upgrade is that it was done using ASTM standards instead of DAL C, which usually applies to these products. “We used ASTM to replace a DAL C component,” he said. “This was a big deal, to get the feet-on-the-street FAA certification folks to follow this new regulatory effort. Resurgent was key to making that happen.”
The Black Hawk radio emulation, however, is a product that meets DAL C, an Army requirement. Avilution is also using the same software to drive three LRUs in another military aircraft type, including an anti-jam GPS antenna, military-grade transponder, and embedded GPS/INS.
Ultimately, Avilution wants to sell its software to manufacturers that want more control of the avionics interfaces in their aircraft, both civil and military. “We’re not expecting end users to fiddle with code,” he said. “OEMs have access to the underlying pieces that support their changing requirements. You can customize it, at the most extreme levels the way the flight deck is built up. You want an altimeter here, the airspeed here, and a gauge to display this parameter here? We’re building a configuration that is modular discrete pieces of software but presented to the pilot as a unified view.”
An example of this is Zenith Aircraft’s installation of the Avilution Unpanel in a CH 750 Super Duty homebuilt airplane. Avilution asked Zenith customers what they wanted in their avionics, and it wasn’t the modern primary and multifunction display setup that has become ubiquitous. The result was a large screen with none of the distractions of instrument flying—because this is a VFR airplane—but with important information such as angle of attack, airspeed, altitude, and fuel level prominently displayed. “Those were the instruments and data that pilots needed that [if they didn’t have it] would most likely get them in trouble,” Spencer said.
Another way Avilution’s software can help is in the development of new electric- and hydrogen-powered aircraft types and presenting information about the level of hydrogen available and battery and fuel cell status. These are new parameters that are easily configured and testable with Avilution software.
“Seaplanes have unique requirements,” he said. The software can be used to create wrong-configuration warnings such as an alert if an amphibious airplane is landing on water with the landing gear down. “That is stuff we can do in software and add as a little configurable piece that flows in with the rest of the system.”
Avilution is now “at an inflection point,” Spencer said. “We’re getting a picture of how significantly faster and less expensive this approach is toward solving avionics issues. I want to see advancement on the government side continue to fund improvements in general aviation, especially those that make it more accessible, reduce the cost of avionics, and provide for simpler interfaces so learning to fly is more easy and safer than what we have today. Hardware is a blank slate the designer can use. This should make it easier [to develop] unmanned aircraft, roadable airplanes, [and other advanced aircraft].”
At its Huntsville headquarters, he said, “We have a unique facility, a combined office and hangar. We write the software and put it on a USB stick, then plug it into the aircraft. It’s such a cool capability to work with the airport to build that blended-use facility that allows software development and flight test in the same place.”