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The Falcon 5X underwent its first simulated flight, completing an important milestone in the development program, in November 2013.

Dassault magnifies focus on its 5X

The “glass cockpit” concept transitioned very rapidly in commercial aviation, replacing familiar analog cockpit layouts to embrace the adaptability of multi-functioning displays and the flexibility to incorporate vastly more information, enabled by the digital revolution.

Today, even the smallest general aviation aircraft can come equipped with advanced digital displays and avionics systems. However, within the civil sector, following several high-profile air incidents, there is a growing view that information overload and perhaps an over-reliance on automation in the digital environment can sometimes present pilots with a very challenging situation, especially when things go wrong.

The debate continues as to where exactly the balance should be between systems that have a high degree of autonomous functionality and the need for pilots to retain a wider 3-D perspective, especially if the computer software is overwhelmed by conflicting data being input from damaged or non-functioning sensors. The problems can be compounded even more when the pilots are flying at night or in storms with few if any visual cues, such as a horizon seen through the cockpit windows.

But things are changing to reflect this concern and one step toward a solution in the cockpit and incorporated in the latest iteration of the EASy flight deck on Dassault Aviation's new 5X business jet is to separate out the immediate priorities in presenting data for managing safe flight, and follow-up actions required later during the flight.

Of course, at all times key information must be available regarding the totality of the flight, both aboard the aircraft and outside where the aircraft interfaces with such factors as airport activities, air traffic management, navigation, weather, and local terrain. But a more intuitive approach on the flight deck can deal with these factors in a logical sequence and help the pilots to react quicker by giving them exactly what information they need, when they need it.

Dassault refers to this as tactical and strategic decision making by the pilots. Developments in avionic systems now allow all the information required by the pilots, from pre-flight checks to final shut down, to be shown automatically, in the right sequence, but presented in a way that makes it easier and safer for the pilots who remain in full control of the aircraft at all times.

The latest EASy II system aims at doing just this, and such is its potential. Four 14.1-in multifunction display units (MDUs) in a “T” configuration can show all the information from the aircraft sensors affecting systems, communications, navigation, and flight management and are key to the pilots’ control over those functions.

The two outboard screens are directly in front of the pilots and are dedicated to short term “tactical” information essential to piloting the aircraft. The traditional presentations are permanently accompanied by data on engine parameters, aircraft configuration, and a crew alerting system.

Two inboard MDUs are stacked vertically in the center of the cockpit to be visible to both pilots and are configurable so they can show selectable ”strategic” information. Typically, the upper MDU would be used to control and display navigational functions, with the lower MDU handling the FMS, systems pages, and checklists.

A new feature is the interactive nature of the automated checklists. As soon as an action has been performed it is automatically checked off through auto-sensing and changes color from blue to green and then opens up the next item on the checklist. It also provides secure options to over-ride or defer any item if need be.

EASy checklists are linked to synoptic system displays. For example, if a fuel-related item is selected on the checklist, a fuel system diagram will pop up adjacent to the checklist window. It shows the real-time position and operation of pumps and transfer valves with a graphic description of fuel quantities in each tank.

Dassault brought into the 5X's design flight controls and displays experience not only from the Falcon family of business jets but also from the advanced Rafale multi-role combat fighter. This is particularly important for it incorporates many thousands of hours of operational military flying aboard air combat planes, and this brings direct first-hand technological feedback that is unavailable to most other manufacturers of business aircraft.

The EASy II system provides a very precise flight path control and automatic trim, with adjustments during configuration changes, and the autopilot functions through the side-stick controllers for setting heading and altitude, with full envelope protection through the digital flight control system. This allows pilots to extract the maximum aircraft performance (such as extreme angles of attack) in instances of instinctive reactions, such as wind shear or collision avoidance maneuvers, without over-stressing or stalling the aircraft.

This is an area where at the design and development stage, Dassault’s fighter heritage is much evident. The new digital flight control system will command all the flight control surfaces, including the slats and flaps and each control surface will be multi-functional to give peak performance at all times. An example of this flexibility can be seen on the aileron, which can function as an aileron, but also act as an air brake.

The Falcon 5X is the first aircraft in the business sector to use flaperons—active high-speed deflection control surfaces that can act as flaps or ailerons. The flaperons will always operate in active mode and will enhance roll authority, but the benefit will be seen very effectively on approach, especially in a steep descent where the flaperons will act like a traditional flap because they will increase drag while maintaining a high lift coefficient. This will allow a pilot to be able to fly a steep approach without increasing the approach speed, even on a normal approach. According to Dassault, this will maintain optimal control while giving a good forward visibility, enhanced by cockpit windows that are 32% larger than on average business jets.

The synthetic vision system (SVS) on the 5X allows the pilot to see the exact position of the aircraft even in instrument flying conditions, and is an important bonus when flying into an unfamiliar destination. The SVS creates a highly realistic image of the surrounding terrain in a simulated daylight VFR condition, using the head-up display symbology and advanced 3-D terrain simulations.

As well as the SVS, the aircraft also has an enhanced vision system (EVS) with nose-mounted sensors that are fully integrated to give even further SA during takeoff, approach, and landing, and also during ground maneuvering at busy airports. This provides an image on the new-generation wide-angle Elbit-supplied HUD and on flight deck displays and gives an improved image of terrain near the airport and of the airport environment in conditions such as fog, haze, and at night.

The Falcon EVS uses LCD HUD technology features unavailable elsewhere. This gives a brighter video presentation with a unique two-mode setting, optimizing the video for either an approach configuration or a more general purpose configuration. It also takes advantage of special IR video processing developed specifically to minimize distortion.

The 5X is still two-three years from entering service, but its highly sophisticated avionics systems that are at the heart of the aircraft undoubtedly help project flight safety capabilities in the direction many pilots have been calling for in recent times.

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