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.
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 isn’t 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 isn’t to say that an EFD1000 retrofit wont require a sizeable teardown. There’s 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. There’s 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 isn’t 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