No Radio? & No Navaid? Never Fear: It's EASy, Planely a Better Way to Fly

What may be most significant about the two most recent high-end business jet cockpits­Gulfstream's PlaneView and Dassault's EASy­is how much they have in common and how they differ.

Both new cockpits are built around near-identical hardware: Honeywell's Primus Epic. This is a tightly integrated, comprehensive system which includes most of the functions related to displays, flight control and flight management.

In the Epic architecture, there is no "radio" as such, and no navigation system. Instead, the entire system resembles a PC network. Communications and sensor functions­air data and inertial measurement­are assigned to line-replaceable hardware modules, which connect to a standard backplane that provides power, cooling and data connections. Primus Epic also uses large-format full-color display screens.

There was a time when this would have meant that any two Primus Epic cockpits would have been very similar. Gulfstream and Dassault, however, have taken advantage of the system's software-driven design to create "branded" cockpit displays with some rather different features.

What EASy and PlaneView have in common is an emphasis on reducing workload by providing the crew with relevant information. Compared with today's glass cockpits, they make more use of graphical and spatial formats for both input and display, and they "fuse" information from multiple sources into single, integrated displays. Both offer navigation displays that combine the aircraft's track, terrain data from the enhanced GPWS, uplinked weather and TCAS traffic warnings in a single color display.

Another feature of both designs is that they reduce reliance on the control and display unit (CDU), the calculator-like device that resides on the rear of the throttle quadrant. Instead of flipping through four-line CDU pages, the crew will control the avionics and plan their flights by using a cursor to navigate drop-down menus on the main screens.

Dassault compares learning to do this to the transition from DOS to Windows.

The reduced role of the CDU reflects the lessons of the December 1995 crash of an American Airlines Boeing 757 on approach to Cali, Colombia. A major factor in that accident was that the crew keyed the wrong beacon into the flight management system, but were not aware of the fact until the aircraft started to turn. If a crew makes such an error with the new systems, the changed course will appear immediately on the navigation display, but will not be executed until the crew accepts it.

The two cockpits do have some distinctive features of their own. Dassault has drawn on its experience with the integrated and automated cockpit of the Rafale fighter and is overtly focused on safety. The company notes that accident rates have leveled off after years of steady decline, and says that part of the solution is "situational awareness"­the pilot's ability to know where the aircraft is, where it is going and what hazards are in the area, without checking displays or charts.

Dassault has located EASy's four screens in a T-shape. The screens in front of each pilot are "tactical" and are assigned full-time to basic flight information. A feature borrowed from the Rafale is that the horizon display shows a projected flightpath vector rather than attitude. Flight control modes and radio/navigation settings also appear on these screens. The upper and lower central screens carry navigation and systems information. An unusual feature of the navigation display­also to be found on the Rafale­is that an elevation view of the planned trajectory and the terrain appears in a window below the God's-eye-view map.

In its PlaneView cockpit Gulfstream installs all four screens in a single row, which senior VP for programs Pres Henne calls "wall-to-wall glass­it's a natural scan, with no nodding." (While Honeywell's literature shows Primus Epic screens in portrait format, both bizjet manufacturers prefer landscape.) While Dassault installs its cursor control device on the pedestal, Gulfstream­after a great deal of research­prefers a sidewall location.

So far, neither system has reached the point where one nor the other can be considered superior. What is important is that the PC-like environment of Primus Epic has given the airframe
developers' pilots and engineers an unprecedented opportunity to design intuitive, intelligent cockpits.

­Bill Sweetman