Pilots are taught from the first day of flight training that flying an airplane is all about situational awareness–visualizing where they are in relation to the rest of the world. The task becomes more daunting when pilots lose visual reference to the ground, such as during IFR operations, because presented with nothing but two-dimensional graphics or text data, the visualization must take place in the pilot’s mind. When the cockpit workload is high, information overload can occur, resulting in reduced situational awareness.
To give pilots a better view, Rockwell Collins has released an improved Pro Line 4 avionics suite–called PrecisionPlus–mated to the Bombardier Challenger 604 to deliver the first in-service business aircraft avionics system with 3-D graphics. To write PrecisionPlus off as a mere software upgrade, however, would be to vastly understate the system’s impressive list of valuable features that Bombardier said “breaks new ground in the large business jet market.”
Steve Belland, Collins’ v-p of product management, called PrecisionPlus “the next logical step in the Pro Line 4 suite.” The upgrade takes a great leap forward at increasing a pilot’s situational awareness while reducing cockpit workload, especially during the critical phases of flight.
AIN recently observed the operation of this upgrade while it ran on a test rig at Rockwell Collins’ Cedar Rapids, Iowa facility.
Using the Collins FMS-6000 flight management system platform, the standard PrecisionPlus upgrade items new to the 604 include automatic calculation of aircraft V-speeds for takeoff and landings, and N1 thrust settings. The FMS-6000 now blends both observed and actual wind to improve flight time and fuel-need predictions. A pushbutton function also converts fuel measurements from gallons to liters and vice versa.
The upgrade also delivers new Polar navigation capabilities that allow pilots to easily steer above 89 deg latitude, as well as full-time DME readout on the multifunction display and long-range navigation position reporting features. In addition to the new 3-D map presentation option, PrecisionPlus offers as options the ability to generate long-range cruise and maximum cruise Mach speeds, a unique new search-and-rescue function and an expanded flight data recorder that offers Part 135 operators the ability to record the parameters required under FAR 135.152.
Standard on the 604
The PrecisionPlus upgrade was certified by Transport Canada in late May, and the system has been standard equipment on each new 604 to roll off the Bombardier line since mid-June. The upgrade is also available now to the owners of 200 older 604s through a series of Bombardier/Collins Service Bulletins.
In the cockpit, the upgrade requires changing only one item, the engine indication and crew alert system (EICAS) control panel in the center pedestal, which also holds the system’s joystick controller. In fact, the only way veteran Challenger pilots would know their aircraft included the PrecisionPlus upgrade, before they actually turn on the avionics, would be if they noticed the new EICAS panel.
The remainder of the upgrade is accomplished through software and avionics module updates. The installed price for PrecisionPlus is between $60,000 and $65,000 for older Challengers. The upgrade adds about $50,000 to the price of a new Challenger 604.
The concept behind 3-D mapping and the rest of the upgrade was both revolutionary and evolutionary, according to Gary Owen, a senior FMS systems engineer at Collins. Owen is co-inventor with Jim Suitor, another Collins engineer, of the FMS-6000’s 3-D map.
“There was a great deal of navigational information out there, but all on flat maps. But people see things better in three dimensions and relate better to pictures than just text,” Owen said. “We decided to marry all this information into a graphical format that would give the pilot a more direct picture that would be more intuitive and easier to understand.”
Surprisingly, the FMS-6000 was already generating much of the data needed to produce a 3-D display, but this information was just not being used for that purpose.
From Bombardier’s perspective, Challenger 604 program manager Robert Vincent said, “In 1997 we surveyed many pilots and operators around the world on the 604’s avionics. Their responses mentioned a number of system nuisances that we wanted to improve. Pilots also wanted lower workloads and faster FMS operations. We wanted to make a dramatic improvement with [FMS-generated] V-speed and thrust management by making them a primary source of data, rather than a supplemental one.”
V-speeds at the Speed of Light
Any pilot who flies the Challenger on multiple legs in a day will appreciate the
FMS-6000’s generation of V-speed data. The only necessary input from the pilot is an ATIS-reported temperature.
The FMS calculates the V-speeds from an OEM-supplied database and displays them on both the MFD and the primary flight display. Owen said, “This is the first commercial certification [on a business aircraft] of computer-generated V-speeds in which the pilot is not required to check with the aircraft flight manual as a backup to that data. By pressing a single button, pilots can now find a comprehensive one-page takeoff reference page that used to occupy four pages in the old system.”
The takeoff reference page includes V-speeds, runway length requirements, maximum takeoff weight and maximum weight to meet brake and tire limits. As a built-in safety feature, the FMS pulls all takeoff numbers from both pilot displays whenever a change is made. Only after one pilot verifies the new data can the numbers be reposted. The PrecisionPlus upgrade system will also solve both actual and required aircraft climb gradients.
This climb-gradient function alone is a blessing for pilots regularly operating the 604 in and out of areas where single-engine climb performance is a constant concern. For example, if the pilot inputs data on a 100-ft obstacle off the end of the runway requiring a climb gradient of 640 ft per nm, the takeoff reference page will immediately show whether or not the aircraft has the required performance. If not, the numbers are colored in amber. The FMS will also calculate how much weight must be removed from the aircraft to clear the obstacle.
The upgraded FMS-6000 calculates takeoff weight limits for any given runway/temperature conditions based on previous pilot entries during initialization. The pilot can toggle through to the current runway surface conditions–dry, wet, slush, compacted snow or ice.
If the aircraft is overweight based on those conditions, that data would be highlighted in amber on the MFD’s takeoff reference page to call attention to the situation. But the system still allows the pilot to make the final decision whether or not to take off.
As with climb gradient issues, the system displays the solution to an overweight problem, too. The resulting calculations also include the required takeoff runway length under the given conditions, as well as the stabilizer trim setting once the pilot inputs the current aircraft c.g. location.
The FMS additionally determines the appropriate N1 settings for takeoff, climb, cruise and maximum continuous thrust with automatic power reserve or a particular target power setting. After the calculation is complete, those thrust parameters are sent to the EICAS and displayed as a cyan bug on the N1 graphic. The pilot can also toggle through various engine bleed settings–wg+cowl, cowl, 10th and off–through FMS line-key functions. These results are automatically sensed and the corresponding thrust setting is calculated.
In addition, PrecisionPlus solves polar navigation problems. “One problem about flying over the poles,” Owen said, “is that above 89 degrees things converge mathematically. We wondered how to present the North Pole since we did not want to use a grid system like the military does. We eventually developed a method to allow the guidance system to operate the same it does below 89 degrees. It goes into a coast mode for the minute or so an aircraft might be in that convergence point over the pole.”
Not surprisingly, a few basic FMS features, such as holding, SIDs and STARs and navigation related to any fix located in the polar region, are not available in the polar region.
Pilots who regularly fly the North Atlantic Tracks know that accurate logging of the trip is almost as important as accurate navigation. In fact, ICAO requires all navigational logs to be stored for a period of six months to track possible gross navigational errors. The upgraded Collins system displays remote oceanic crossing information in a format organized the way the pilots must read the information to ATC. It also stores the previous 100 waypoints in the FMS’ memory.
Listed as an option to the PrecisionPlus upgrade is the revolutionary 3-D flight-plan map, which delivers an intuitive graphical representation of the programmed flight plan and predicted path on both pilots’ MFDs. The central-panel joystick allows each display to be fully customized to the most effective view for each pilot.
The graphical interface uses an aircraft icon to help orient crews to the Challenger’s position in space. The 3-D system offers pilots the opportunity to position their view from just slightly behind the aircraft’s icon or in front with the aircraft coming directly at them, or some combination of these perspectives.
Another new feature that comes bundled with 3-D mapping is long-range cruise and maximum cruise Mach calculations, which are retrieved from the OEM tables resident in the FMS. With the recently announced STC for the Challenger’s Safe Flight autothrottle system, the FMS-6000’s speed outputs can be directly inputted to the autothrottles for fully synchronized, hands-free operation.
Inside the cockpit, the upgrade adds a few new functions to current buttons, as well as one entirely new control. The FMS’s old up, dn and skp buttons now perform their primary functions related to checklists, but thanks to a context-sensitive format the FMS also knows when the aircraft is no longer in the checklist mode.
This allows the skp button also to function as the basic on/off toggle switch for the 3-D mode. The up button produces an instant plan view of the flight plan on the MFD, while the dn button cycles through to a side view of the flight plan or approach chart.
Once the 3-D mode is selected, the pilot may use the pedestal joystick to orient the picture to any comfortable view between zero and 360 deg laterally and zero and 90 deg around the vertical axis.
Owen added, “What is really significant about the joystick is that it allows each pilot to orient their 3-D picture exactly the way they like to see it for optimal understanding of the information. The possibilities are almost infinite.” But to some pilots, infinite implies too many choices, so Collins offers a few preselected views.
As an example, if a flight plan is stored in the system and the pilot pushes the plan button, he or she will see a traditional 2-D display of the departure route. Pressing the 3d button automatically changes the map view to a 22-deg lateral and 75-deg vertical presentation, relative to the inbound course to the map’s center. Sequencing the 3d button several times toggles the view between 22 deg left and right of the selected course.
The other new button is sel/auto. Selecting auto maintains the same relative 3-D picture each and every time 3d is selected without additional user input.
Collins has maintained the same display color-coding and line composition as on previous FMS models. Solid white lines represent the course across the ground. A solid green line indicates what the aircraft will actually fly in a coupled Lnav/Vnav configuration. A dashed line, in either color, represents a change to the original course or climb profile.
When operating in 3-D mode, there is also a cyan-colored aircraft that moves along the ground track on the display in what Collins calls “shadow” mode, as verification of the aircraft’s path in relation to the programmed course. There are also pointers on the predicted path lines to avoid confusion over the direction of the aircraft.
The aircraft symbol in the 3-D mode banks its wings and raises or lowers its nose when climbing or descending as a reality check as well. Collins cautions, however, that the aircraft icon is for information only and should not be used for aircraft control. The entire 3-D presentation hovers over a grid across the simulated horizon, with range marks and cardinal directions marked on the grid to keep things in perspective.
For an example of 3-D mode in action, consider a nonprecision approach. The pilot previews the procedure, including a synthetic glideslope, as well as the aircraft’s position relative to that glidepath.
Without looking at the vertical speed indicator, the pilot can tell instantly, once the approach has begun, whether he is above or below the glideslope simply by looking at the miniature aircraft’s position relative to the slope. While the aircraft icon is not to be used for actual navigation, it represents the first time a pilot can see a graphic depiction of the airplane’s deviation from the glide.
Life in 3-D
3-D presentations truly shine in high-workload situations because there is little pilot interpretation necessary to understand the situation. Consider when poor weather raises the distinct possibility of a missed approach. Many crews will try to memorize their first actions should the miss occur.
But now, with the ability to preview the missed approach in 3-D, the miss is much easier to visualize. In preview, the ground track of the missed approach procedure is displayed in cyan while the predicted flight trajectory is outlined in solid green lines above. The cyan color changes to white when the missed approach becomes active, while the flight trajectory remains green.
When the aircraft enters a hold, the 3-D presentation constantly moves, offering pilots the best view possible of what their aircraft is actually flying. The PrecisionPlus upgrade includes an automatic scaling feature that delivers the largest possible version of the presentation on the MFD for increased accuracy.
The idea for a 3-D presentation of FMS data, as well as the other unique features of PrecisionPlus, evolved partially from users, according to Owen. “Our customers said they were taking the plan and the profile views and trying to turn them into 3-D presentations in their heads anyway,” he said. “They wanted more vertical information about their flight plans. Much of what the update incorporates came from direct user input at Collins’ annual operator’s conference as well as input from the company’s own 604 pilots.”
Owen also admitted, however, that development of the 3-D concept most likely would not have happened much sooner than it did in 1997 because “we were pretty much pushing the envelope on the computer processor’s ability to do the job at that point.” Having the right people in place at Collins at the right time also helped.
Owen, a former Sperry engineer, has a background in FMS, while his 3-D co-inventor, Suitor, was an expert on information display.
PrecisionPlus began life as a series of computer simulations that evolved into a prototype and finally a certified finished product in search of a home that it found on the Challenger.
“We started out with a version on a PC that we could show to pilots. They fell into two groups, those with lots of FMS experience and those with very little or none,” Owen said. “We moved from a computer simulation on a desktop to an airworthy prototype in a fair amount of secrecy in less than two years.
My partner and I presented a paper on the prototype of the 3-D map in spring 1997 and the feedback was very positive. But we faced two problems with this technology. One was solving the 3-D issues and the other was finding an airframe manufacturer whose aircraft would work for us. I never felt our problem was solved just by developing the technology. It needed the right application platform.” The timing was perfect with the Challenger.
Collins’ Belland said the number of changes necessary during the prototype stages of the certification process did produce a few revelations. “It was probably more of a surprise to us because we thought we had so much of this upgrade finalized before Transport Canada and the FAA [saw the prototype]. Many of the changes were subjective from people who had never before seen a 3-D presentation. They included things like color, which was always an issue, or how the picture rotates or how we would deal with potential pilot confusion issues. We thought the certification process would take only a few months, but it actually took nine months.”
But Belland also believed this upgrade certification experience would change the way Collins approaches future endeavors. “We’re looking for ways to get written approval earlier in the [certification] process, not just verbals.”
Cockpit information overload can overwhelm a pilot, leading to cockpit confusion and distraction. AIN asked Owen how his team knew how much information was too much.
“We took our best shot with a prototype, quite frankly. We then gave it to our own pilots to review early on in the development cycle, as well as other professional pilots, human factors experts and regulatory pilots,” he said. “What made this upgrade easier was that we were not really changing anything, but rather adding more information to the system. But the layout was not arbitrary by any means.
“We had many meetings with our FMS user group and asked them directly what they liked about the current system, what we should add or what might need improvement. Then Collins and Bombardier prioritized all the possible changes, knowing full well that not everything could be included. So Collins and Bombardier went with the things the majority of users felt they needed as soon as possible. The pilots are the ones who told us they wanted a North Atlantic position-reporting page, for instance. They also told us how they thought it should be set up.”
Interestingly, Owen said that input often came from customers who used competitive products. “People would tell us what not to do, as well as things they thought we should add.”
Collins has updated its Vista (visual integrated software testbed for avionics) training system to provide hands-on FMS training to users at training centers around the world and directly at flight departments whose computer hardware meets Vista’s heavy system requirements. There is also a less memory-hungry version that will run on a laptop to aid pilots in learning how the upgrade works.
When it comes to the 3-D portion though, Owen said he saw pilots hop into the cockpit after just a short classroom briefing on PrecisionPlus and easily grasp what was happening in the aircraft. “The system is that intuitive,” he noted. “But that simplicity came after considerable prototyping and in-house evaluation.”
If there is a downside to this upgrade, albeit even a small one–and from the perspective of myself after observing the Collins rig for only a few hours–it is that a poorly trained pilot could end up with an overwhelming 3-D display covered in colored lines. I saw just that the first time Owen previewed a missed approach before shooting an “actual” approach. Having someone along for the first few flights who can quickly clear a cluttered screen would be a big help.
Another potential issue was how easily a poorly trained pilot could orient the display in a way that might be confusing, rather than helpful. When the 3-D model is flying away from the viewer, figuring out which way is left and which is right is easy. But if the pilot selects a view that has the aircraft appear to fly at the viewer, figuring out what the aircraft is really doing can become chaotic–right is left and left is right–hence Collins’ warning about not using the 3-D presentation for aircraft guidance.
Additionally, a pilot can orient the 3-D display so that the traditional north picture is no longer at the top of the screen. The top might now be east. While all of these issues will most likely right themselves with just a few hours of flight after the upgrade, 3-D may still take a little getting used to.
Any pilot who views the 3-D map will almost immediately ask, ‘Why not integrate the 3-D picture with an Enhanced Ground Proximity Warning System (EGPWS)?’
Collins certified the PrecisionPlus upgrade with the 3-D map as a starting point in the technology. Owen admitted that adding EGPWS is “a natural direction [for PrecisionPlus] to go. But we just aren’t there yet. EGPWS is coming, as is TCAS. But we need to move ahead in small steps first.”
Since Collins bought Flight Dynamics in 1999, developing a link between the Head-up Guidance system and 3-D would also seem natural. Owen said that while that might happen in the future, pilots should not lose sight of the fact that the 3-D system is for enhanced situational awareness and not aircraft guidance.
Belland concluded by saying, “This upgrade included everything we wanted to present to our customers. Another major upgrade should not be required for at least three to five more years.”