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The Glass Transition: Training, Practice Time Can Ease the Change

Have you flown behind an analog panel lately? If so, you may not be doing so for much longer. With conversion options expanding, odds favor that panel getting a glass-cockpit makeover in the near future.

With a rectangle computer display replacing that well-known pack of six round flight instruments, and data presentation that differs considerably from the analog format, it's no surprise that crews might feel lost, even uncomfortable, flying behind a panel with little resemblance to its former self.

From Spinning-Mass to Solid-State

What's really new about glass cockpits? Well, other than what they portray, pretty much everything: how they work, what drives them, how they share software and display failure modes, and, most significantly, how they actually look.

In place of three of those round dials, primary flight displays generally show the three air-data parameters on vertical indicators flanking the attitude indication. Similarly, the attitude indicator (AI) may be as wide as the square-cornered screen, with the directional gyro completely surrounding it, partly surrounding the AI or presented below the AI.

Most systems superimpose navigation indicators over the directional gyro arc, or overlay a glideslope and localizer indicators on the AI presentation. These systems use no fast-spinning metal gyros to wear and fail, no mechanical linkages moving needles for airspeed, altitude or vertical speed, and no failure-prone air pumps.

Electricity alone powers the solid-state sensors providing references, with the computers translating data for display and, of course, screens displaying everything. Failure modes differ, with a sudden complete loss of electricity being the simplest, most-straightforward failure mode. Other failure modes, which can be far more complex, can and do occur. Both primary and back-up air-data sensors will suffer should a sole pitot/static system experience problems.

Equipment-Specific Knowledge, Proficiency Important

Since the early stages of the glass to analog cockpit evolution, safety investigators have been well aware of how the differences between the two types of panels could impact pilot use and flight safety.

Europe's two-year Collaboration on Transition Training Research for Increased Safety, or ECOTTRIS, project studied glass-cockpit issues as a possible factor in several high-profile commercial accidents.

In the U.S., reports to NASA's Aviation Safety Reporting Service (ASRS) exposed glass-cockpit adaptation and training issues among highly experienced business-turbine pilots. The National Transportation Safety Board in March 2010 published its study, Introduction of Glass Cockpit Avionics into Light Aircraft, which suggested that "the introduction of glass cockpits has not resulted in a measurable improvement in safety when compared to similar aircraft with conventional instruments."

In addition, safety issues in two areas – training and reliability – led experts to conclude that pilots need "sufficient equipment-specific knowledge and proficiency to safely operate aircraft equipped with glass cockpit avionics."

There are particular challenges for operators who retrofit existing aircraft with glass-cockpit technology when it comes to training to proficiency on a new system. Training options and support are more varied: full simulators may not exist for retrofitted aircraft, and instruction offered seldom matches factory-sponsored, professionally performed transition training typical of new-aircraft delivery. Nonetheless, avionics makers and training organizations offer substantial training support.

Training to Type

While glass cockpits provide common data across all makers, differences in appearance, function and interfaces exist among product lines, prompting instructors and safety authorities to encourage system-specific training for pilots transitioning to glass cockpits.

Avionics makers Aspen, Garmin, Honeywell, Rockwell Collins and Universal Avionics, as well as airplane manufacturers, urge specialized training for users of their systems. Courses range from two to four days, and sometimes longer. Regardless, all agree that no pilot should fly a new (or new-to-them) glass cockpit without first training to proficiency and system knowledge.

What Are Some Key Components of Glass-Panel Training?

  • Power sources: How the panel receives and uses power, including standby or back-up systems, their capacities and a method to match load to generating limits in any electrical failure
  • Sensor(s): Failure modes and knowing the impact of failures, which are critical in the event of either a failed Attitude and Heading Reference System (AHARS) or ADAHARS (an AHARS with integral air-data sensing)
  • Reversionary Modes: Comfort and competency using built-in back-up functions so crew can move data from a failed primary flight display to a functional screen, such as the multifunction display
  • Air-Data: Knowledge of the system's connections, with both main and standby instrument clusters; pitot/static system plumbing gives air-data sensors contact with the atmosphere
  • Standby systems: The best stand-by solutions closely resemble the look and function of the main systems they back up, but should run as independently as possible; separate power in the form of a back-up battery is best, compared to one wholly dependent on the main electrical sources; and a dedicated pitot/static system, while rare, could be priceless
  • Flight-Control System architecture: Know whether the autopilot depends on the attitude sensors feeding the PFD, whether the flight-control system employ stand-alone sensors – and how to override a runaway flight-control system
  • Programming and controlling functions such as moving-map displays, alternate screens with traffic or weather, even simply using VHF radios, the GPS or other navigation sensors.
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