Avionics for Your LSA

Michael Schofield, director of marketing for Dynon Avionics, says that they often get telephone calls from owners of SLSAs (built to a conforming model by an OEM) who want to change the avionics and are surprised to learn that only the manufacturer of the LSA can approve the change, unlike the normal supplemental type certificate process.

“They can't just dive into it and make a change,” says Schofield, because under the light sport category, the avionics are part of the approved equipment during LSA certification. “It’s a pretty typical support call when someone will say ‘I have an SLSA and I want to make a change.’ They are surprised to learn that they have to go through the manufacturer to get permission for the change or else they have to take the aircraft out of SLSA and put it into the experimental or ELSA category.”

The downside of this is that ELSAs—with E standing for ‘experimental’—cannot be used for aircraft rental or flight instruction. If the aircraft is a revenue-generating device, changing into this category may not be in your best interest.

Dynon Avionics is based in Woodinville, Washington, north of Seattle, and it has a satellite operation in Portland, Oregon. The company, founded in 2000 by a pilot and semiconductor entrepreneur, makes avionics for light aircraft. According to Schofield, in the beginning, the company’s largest audiences were the builders and owners of experimental aircraft looking for functional displays that didn’t swallow the whole panel.

“Back in 2004, we were already the experimental market share leader making avionics for [Van’sAircraft] RVs and Glasairs and whatnot, and when light sport came about, we realized it was an opportunity.” Schofield notes that Dynon is the recognized first participant in the LSA avionics market, followed by Garmin and a few smaller avionics manufacturers. Dynon also works with OEMs as they design panels for new aircraft.

The product designs are pushed by the customer’s desires, said Schofield, and they continue to evolve. “The original EFIS D-10 was released in 2003, and in 2020 we were incorporated [into instrument panels] pretty quickly. We had the whole first generation line of 4- and 7-inch EFISs [electronic flight information systems], and the SkyView—the current platform—came out in 2009. The SkyView HGX—[which came out in 2018] is the latest incarnation with the touchscreen and a better interface.”

The avionics need to be usable, but have a minimal footprint, says Schofield, who describes it as a balancing act. “One of the things that we focused on in the initial issue of SkyView was the minimal footprint, and it has carried through. So if we have a 10-inch screen, we don’t want to have too much bezel around it, although you may want to grow that for the internal space because maybe you can make circuit boards fit better if you grow it a little. But for every quarter inch you grow in every direction, you lose the ability to fit [it into] some model of aircraft.”

For the pilot transitioning from round dials—the so-called ‘steam gauges’—there may be a bit of a learning curve, says Schofield, although it is nowhere near as challenging as it used to be, as most pilots are more accustomed to using panel-style technology. “We used to hear, when the EFIS was new: ‘I don’t know what I am looking at.’ That has evolved over the last 5 to 10 years as everyone has iPads, iPhones, and super-light laptops. People are getting more familiar with the technology. We actually came out with a feature on the EFIS display where you have wall-to-wall synthetic vision that doesn’t look like an attitude indicator—it is like looking out the window.”

Schofield adds that the instruments shown on the display are created by the software, and with a few button taps, the screen will revert so that instead of tapes, the familiar round gauges appear.

Color coding is used for engine and system monitoring gauges. Red signals an emergency condition, yellow says caution, and green highlights normal operations. This can make it easier to determine if the aircraft engine is having a problem because the colors are easy to discern—as opposed to an analog read-out where the pilot must remember which values indicate trouble.

“You don’t have to actively think about what is wrong—just scan quickly. If it is red, you know,” says Schofield. “If it is red there is a voice alert [such as] ‘oil temperature high’ or whatnot. There is a lot lower workload—once you get over the ‘ooh there is a lot there’ aspect.”

Programming the avionics is fairly intuitive, says Schofield. “I could teach you by taking you through two or three operational principles: This is how the touch screen works, etc. The programming is done by a combination of buttons and knobs. We did it that way because in light aircraft it can get pretty bumpy and an outstretched arm on a flight cannot be perfectly precise,” he explains. 

What avionics the owner selects for an LSA panel upgrade is driven by a combination of aircraft mission, budget, and panel space. 

“It is important [that the owner] understands how the systems go together, and what equipment is needed for a given mission, and whether it is a new customer or someone who is making a change to an aircraft.”

Dynon’s reps are often asked, “What do I need if I am going to (insert mission here)?” Changing a panel from “VFR to IFR is one of the big things people want to know about,” says Schofield, because redundancies are needed in an IFR panel. “You want two of everything that matters,” he says, explaining that VFR-equipped aircraft may only have one ADAHRS into the display. The ADAHRS module generates data for use by SkyView to calculate the artificial horizon/synthetic vision display, gyro-stabilized heading indicator, airspeed indicators, altitude and vertical speed indicators, slip/skid, turn rate, angle of attack indicators, flight path marker, and winds aloft speed and direction indicators.

For IFR flight, you’ll want two ADAHRS, says Schofield. “Or even for VFR cross-country [flight] you would want two, because if one screen goes dark the information on that screen jumps over to the other screen.” There are also lithium-powered batteries and an option that will give the aircraft approximately 60 minutes of energy to get to the ground.

“We tell them they want a good amount of redundancy, dual displays, and at least one battery backup.”

According to Schofield, Dynon has a network of authorized service centers that have been trained to install the company’s avionics. “Homebuilders have been installing our stuff for years. We know that they are A&Ps and IAs, and we know that we built products that people can install for the first time by themselves, because that is how thousands of people have done it already. We make sure you have a qualified installer signed up when you buy from us. It could be a shop or an A&P/IA and on the STC permission statement [for regular type certificated aircraft], which is something you need from us that it will have. [It states] ‘this STC can be applied to this airplane, by this AP/IA or shop.’” In that case, says Schofield, the customer is kind of self-selecting who will do the installation, noting that sometimes, these A&P/IAs transition into authorized installation centers.

For owners already under the ELSA category or making the transition to it from SLSA, Dynon builds the panel, the wiring, and the advanced control module, “which is kind of like a harness and power distribution system, as it has electronic circuit breakers and the literally that goes into a box or crate, and it gets mailed to the customer who can then rivet into their panel of the aircraft,” says Schofield.

“All they need to do is connect some wires and follow some instructions. Eighty percent of the paneland wiring is complete by the time it gets to them,” saving time and energy.

This article was originally published in the April 2023, Issue 936 of  FLYING.