Roll Your Own Glass: No Ideal Solution

The aftermarket is rich with retrofit displays for the radio stack and instrument panel. But even after investing a bundle, most solutions still come up short.

As we pointed out in our April issue of Aviation Consumer, there are some sweet deals on used, glass-cockpit aircraft. But for many owners, this jump in the ownership food chain might not be practical or affordable.

If youre perfectly happy with your current wings (or just have good reason not to sell right now) but lust for the big-screen glass that dazzle front and center in new cockpits, you have options. Unfortunately, there are caveats a-plenty.

S-TEC 55X autopilot


Our definition of glass here includes a primary flight display (PFD) and some kind of modern multi-function display (MFD) and modern IFR-GPS the likes of Garmins GNS-series navigators. Traffic and satellite weather are in the mix as well. Were talking fully certified systems focused toward certificated aircraft-nothing experimental or portable installed on the panel.

Electrical Limitations

Step one is a review of your stock electrical system. New, all-electric aircraft require electrical-bus and electrical-system redundancy. Your old airframe likely doesnt have dual batteries, dual alternators or dual electrical busses, and equipping a 70s-vintage Skylane to these specs just isnt going to happen.

Some equipment wont accept a 14-volt input voltage, including the popular Avidyne EX500 MFD. That means a current-hungry voltage converter if installed in a 14-volt system.

That brings us to the other major issue: overwhelming the electrical system of an older bird in supporting all those fancy new avionics. Many 14-volt alternators werent intended to keep up with this intense charging demand. Some owners with full panels report increased incidents of alternator failure or screen blackouts when running high-draw accessories like landing lights or gear and flap motors. Have your shop do an electrical load analysis for your proposed avionics suite. And always keep a healthy battery in the aircraft. It works hard.

Reworking the original bus and installing properly rated push/pull circuit breakers and proper labeling can be surprisingly pricey and time-consuming. Is it worth it to rewire analog engine gauges and warning lights while the panel is open? How about replacing old switches with modern, lighted rockers? What about all that old wiring lurking behind the panel and woven through the airframe? This can get expensive even before putting in the new stuff.

Budget: Aspen EFD1000Pro

While it wont fill the entire pilots six-pack, the Aspen EFD1000 Primary Flight Display series offers an easy way into a solid-state PFD. The STC, via AML, requires the retention of most of the existing steam-gauge flight instruments. We covered the EFD1000 in our June 2008 issue.

Since then, the EFD1000 has been well-received and has mostly performed as advertised. An Aspen upgrade should be a painless upgrade for the experienced shop that has a handful of EFD1000 upgrades under its belt. Wiring and interface hurdles that were hassling in the beginning should now be a non-event. This isnt to say that an EFD1000 retrofit wont require a sizeable teardown. Theres just less uncharted territory now. The reduced amount of panel work is a bonus when upgrading to the Aspen PFD. The unit clips into a bracket that sits where your attitude and directional gyros used to live.

The Aspens six-inch diagonal display offers a bright and intuitive presentation, and nearly all of the features you would find in the most sophisticated PFD. Theres also the added bonus of integral GPSS digital roll-steering, but thats gotten mixed reviews from some owners. Some say that this integral steering interface isnt as precise as GPSS that originates from the autopilot computer (mainly, the S-TEC 55X and the ST-901 stand-alone GPSS steering system). Aspen is close to

 Garmin GPS


releasing the MFD companion to the PFD, which offers a reversionary display for backup. In doing so, it fills more space in the standard six-pack and adds MFD capability for playing weather and traffic.

A typical EFD1000Pro retrofit should fall in the $14,000 price point, not counting any external nav sources. Add a GNS430W to the mix and you could have a basic glass setup for roughly $30,000. This price point is a number many owners can live with, and has made the EFD1000 a popular install.

Bigger: Garmin G600

Garmins G600 PFD/MFD combo isnt the scaled back G1000 that some expected it would be. With some panel modification, the G600 fits in the existing six-pack area. Its MFD can be thought of as a mini-GMX200 (Garmins stand-alone, retrofit MFD). But if theres already a well-rounded MFD in the panel like a GMX200 or Avidynes EX500, the cost of the G600s integral MFD is essentially wasteful.

If we could find one technical fault of the G600, it would be its inability to interface with popular existing analog navigational systems such as the Bendix/ King KX155. The Garmin AT SL30 nav/com, as well as the Garmin GNS 400-, 500- and 480-series navigators, are the intended complements to a G600. There is an ADF interface for you old-schoolers.

The G600 accepts an operating input voltage from 10-40 VDC, making it a player for many aircraft. In fact, well over 300 aircraft are on the AML STC listing. The G600 offers dual 6.5-inch diagonal screens housed in a single chassis/bezel. It sits 6.7 inches high and 10 inches wide, and weighs roughly 6.5 pounds. The GDC74A air/data computer, GRS77 AHRS, GMU44 magnetometer and a temperature probe are mounted remotely. As with any PFD, youll need to retain standby airspeed, altimeter and attitude instruments on the pilots panel.

Disappointing is the fact that the G600 doesnt emulate autopilot roll and pitch commands. Owners of attitude-based autopilots are stuck with expensive and unreliable vacuum-driven gyros for their existing autopilots. It will accept flight director inputs for a command presentation, and the heading and course commands coming from the G600 will drive most autopilots.

The MFD side displays GPS flight plan data, XM weather and radio input, TIS and/or TAS traffic, terrain (advisory and TAWS-B) and Jeppesen charts and SafeTaxi.

Some G600 installations will result in major deviations from the original panel layout. Displacing the standby instruments may mean reusing the original panel wont be an option. The solution is cutting a new panel from scratch. The equipment has a list price of $32,390 with the charts option, but a G600 that requires a new panel could approach $50,000. Add to that the GDL69A XM system, a pair of GNS430W navigators and the upgrade approaches $80,000. That still doesnt include traffic, audio upgrades, antenna work or any other miscellaneous items that pop up during major upgrades.

Biggest: Avidyne Entegra

Arguably the first mass-produced glass cockpit for certificated aircraft, the Avidyne Entegra, which includes the EX5000 MFD and EXP5000 PFD, made its debut in the Cirrus SR22 and soon became the standard for Cirrus and many Piper models.

The EXP5000 PFD measures 8.5 inches high, 10.7 inches wide and weighs 12.4 pounds. Its screen is a 10.4-inch diagonal color active matrix LCD. There are both portrait and landscape versions of the PFD. The PFD takes traditional pitot and static inputs, and utilizes a remote three-axis magnetometer. Theres no autopilot emulation, except for heading and course command.

The huge FlightMax EX5000 MFD measures the same 10.7 by 8.5 inches, making it impossible to contain in a standard six-inch-wide radio stack. The better option without having to redesign the panel would be to go with the smaller 5.5-inch EX500, which will mount in a standard stack.

Since the Entegra is blanketed under a Type Certificate for some popular aircraft models, aftermarket retrofit is theoretically possible. We would think it would be easy to load an Entegra suite in a late-model Saratoga, for example, since such a ship was once available from Piper as equipped. Once shop told us, however, it might not be that easy or practical. Apparently, an FAA FSDO barked at the engine

 JPI 900-Series Engine Monitor


parameter display interface thats included in the suite integration. The sticky point apparently fell upon removing the stock factory analog engine gauges, since a particular serial-numbered aircraft was approved with such factory gauges. As usual, we suggest hammering out these certification details before getting too deep into the project. But if a Field Approval is what a given FSDO requires for the sign-off, having a like model thats already been fitted, even if its an OEM equipage, is helpful.

Theres an Entegra retrofit STC in place for the Cessna 210 Centurion (both normally-aspirated and turbo), larger Cessna twins including the Cessna 300 and 400-series twins, as well as for the 200-series King Air through the Avidyne Alliant retrofit. A dual-screen Envision retrofit package has a list price of $87,830 and doesnt include installation or GPS navigators. A single EXP5000 PFD lists for $29,895 and EX5000 MFD is $16,990 with CMax Jeppesen charting software.

Retrofit Hits: Chelton EFIS

The Chelton FlightLogic EFIS system is certified for retrofit and includes dual, high-resolution displays, which can function as PFD or MFD. Unlike other systems for retrofit, synthetic vision and highway in the sky is the driving technology of FlightLogic and the situational awareness afforded by the technology is arguably unmatched. FlightLogic is more of a heads up presentation than traditional EFIS, although traditional flight instrument presentation is included. The MFD can be transformed into a PFD with a button push should the PFD fail; the PFD has an unusual-attitude recovery function.

The AML-STC covers popular models, from the Cessna 172 to Part 23 Class III and IV turbine aircraft. Each 4.5-pound screen measures 6.25 inches wide by 5.4 inches high. The MFD is easily mounted in the radio stack, with stature much like a GNS530. A remote AHARS sensor weighs just shy of five pounds and contains triple sold-state magnetometers, angular sensors and accelerometers. Theres also a remote air-data sensor and a remote WAAS GPS receiver. The PFD displays obstructions in 3D as well as traffic from several TIS or active-traffic receivers. The system can also display data from the WX500 Stormscope lightning sensor.

Most Chelton suites use Garmin GPS navigators and traditional autopilots, but theres a rich compatibility with most popular nav and GPS systems. Pricing for the Chelton FlightLogic equipment is $67,152 for a dual screen setup, not including any other avionics such as a GPS navigator. Panel work should be a reasonable venture, since one of the displays can fit in the main stack. There are also three- and four-screen configurations for larger aircraft and helicopters.

On The Horizon

Honeywell has promised the KFD840 retrofit PFD for a couple of years, so were not holding our breath. Still, an 8.4-inch display, internal ADAHRS, optional engine instrument monitoring and projected price under $20,000 is promising. Its marketed with the new KSN770 GPS/NAV/COMM box, which is positioned against Garmins GNS530W.

Avidynes clean-sheet eight-inch PFD4000 PFD also looks promising. It would replace an existing six-pack and has some advanced features, especially in two-screen setups.

Dollars and Sense

Given the costs and downtime of a major glass upgrade and the deals on existing, factory-glass aircraft, we think seriously considering buying used factory glass must be part of the upgrade decision process. None of the aftermarket glass PFD systems provide seamless primary pitch and roll guidance to autopilots like Garmin G1000 with an integrated autopilot. Youll need to buy factory-built glass for that.

That said, there are reasons to upgrade rather than buy in. The owner of a well-equipped and heavily-modded Archer told us the obstacle between him and a late-model Cirrus SR22 was unloading his Archer without giving it away. Even after adding an Aspen PFD, he was far better off on paper than the SR22 would look, considering the loan, insurance and money lost on his current aircraft. The owner of an early-60s, V-tail Bonanza told us his upgraded panel has everything and more than he could find in a brand new airplane. And theres the appeal of a customized vintage ride rather than a “cookie-cutter” model fresh from the assembly line.

As for our pick for glass upgrades, we think an Aspen EFD1000Pro with a couple of Garmin GNS-series navigators offers the most bang for the buck. The Aspen display is the smallest PFD out there, but its the most cost effective and easiest to retrofit. It also breathes new life into an older autopilot with its integral GPSS steering. Garmins G600 represents a good value, since it brings a full-featured MFD to the table along with a decent sized PFD. Call it our pick for getting close to factory glass on a wide range of aircraft, especially if you have the supporting avionics and dont already have an MFD.

Editor in Chief Larry Anglisano has been a staple at Aviation Consumer since 1995. An active land, sea and glider pilot, Larry has over 30 years’ experience as an avionics repairman and flight test pilot. He’s the editorial director overseeing sister publications Aviation Safety magazine, IFR magazine and is a regular contributor to KITPLANES magazine with his Avionics Bootcamp column.