Honeywell says the reliability track record of the E-Jet Primus Epic suite, the software and hardware that drives the digital avionics, integrated utilities and fly-by-wire flight controls, has vastly improved since E-Jet launch and is no different from that of other complex avionics suites.
"Our contribution to schedule interruptions has steadily gone down," says Jim Klucar, director of Embraer customer engineering at Honeywell. "Interruptions (delays, cancellations and turn backs per 10,000 departures) are down by a factor of three in the past three years, and the total aircraft dispatch rate has improved over the years."
Klucar and Randy Robertson, vice-president of electrical systems at Honeywell, say there have been three "major" upgrades in software lineage from the initial load for the E-Jet family, a typical number they say, for new aircraft certificated with "heavy" pilot interfaces, such as fly-by-wire. "For these types of applications, there may be a new software load as often as every six months, then on to every 18 months," they add. "This is not unusual for a brand-new airplane with a brand-new set of systems."
In response to airline complaints that software fixes have introduced new errors, Klucar and Robertson say that "every load we've delivered to the fleet has net improvement. We have a few cases where we may have introduced something that wasn't there before, but that's been the exception in every load. The net on every load has been an improvement."
Robertson says Honeywell released a new version of the software about a month ago, a change that goes directly into the production line at Embraer and is sent to the fleet as a service bulletin. The software change itself comes in the form of a compact disc with a new part number.
Primus Epic hardware changes have also been necessary. Klucar says Honeywell has had to campaign "a couple of modules" and circuit cards since launch, a situation he says is "rare". Typically, retrofits are done on an attrition basis when improvements are found that increase reliability.
The reliability of the Honeywell avionics has improved by "a factor of three" since service entry