Pilot Report: Garmin G1000 NXi
Next-generation system leaps ahead of the original
This article appears in the March 2017 issue of Business & Commercial Aviation with the title “Garmin G1000XNi.”
The Garmin G1000 made its debut in turbine aircraft at the 2002 NBAA Convention when Russ Meyer Jr., then chairman and CEO of Cessna Aircraft, announced that the system had been chosen for the Citation Mustang, the Wichita firm’s new entry-level light jet. The G1000 was smaller in size, lighter in weight and more powerful than any previous avionics suite in its price range.
When potential customers peered inside the Mustang’s cockpit, they discovered that Garmin had moved upmarket with features and functionality that proved it was ready to compete in the turbine market.
But the original G1000 was developed in the era of the Blackberry, plasma TVs and iMac G4 desktop computers. Now, consumer electronics seemingly are light years more advanced. And so are integrated avionics systems.
In January 2017, Garmin announced the G1000 NXi, a second-generation system that takes full advantage of 15 years of technology advances. The successor system has dual core processors, 250 times more nonvolatile memory and a whole raft of other computer power upgrades that slash boot-up time by one-half, provide considerably better graphics refresh rates and take the lag out of image zooming and panning. In short, the G1000 NXi has been upgraded with many of the bits and pieces used in Garmin’s more expensive integrated avionics systems, such as the G2000, G3000 and G5000. The displays, for example, have adaptive LED back lighting that produces truer colors and crisper graphics.
The next-gen G1000 has been upgraded with dual integrated GSU 75B integrated air data/AHRS boxes that save weight and space compared to the first generation’s separate GDC 74B digital air data computers and GRS 77 AHRS units. Both the GSU 75B and GRS 77 use GPS, magnetic heading and air data for attitude and heading computations. Notably, they have relatively high drift rates when such inputs are lost. And some Garmin integrated avionics systems using the GRS 77 AHRS reportedly have experienced attitude indicator and yaw damper degradation with loss of the GPS signal.
For operators needing higher performance AHRS, Garmin offers optional GRS 7800 units that have substantially lower drift rates and considerably less-restrictive geographic operating limits. The GRS 7800, for instance, is designed for full functionality up to 80 deg. north or south latitudes. And it can provide reliable attitude information for a considerably longer period of time after GPS signal loss than the aforementioned AHRS or AD/AHRS. GRS 7800 boxes are paired with optional GDC 7400 digital air data units to provide AHRS and air data information for the G1000 NXi.
The G1000 NXi has an impressive feature set. Optional or standard are SurfaceWatch, which warns flight crews if they’re attempting a takeoff from a runway that’s too short or a taxiway; Flight Stream Wi-Fi/Bluetooth connectivity that allows transfer of flight plans and avionics databases from iPads and other PDAs; visual approach guidance; and several HSI map modes. Sirius/XM satellite radio weather is standard and the optional Garmin GSR56 Iridium satcom radio adds connectivity for worldwide weather, voice calling and text messaging. Both satcom services require subscriptions.
When buyers opt for extra-cost electronic stability protection software, they also get an autopilot-coupled go-around capability that only requires the crew to press the go-around button and then make thrust or power adjustments and change aircraft configuration to execute the missed approach procedure (MAP). The autopilot handles all the flying chores, just as with the latest integration avionics systems furnished by Honeywell and Rockwell Collins in high-end turbine business aircraft.
The G1000 NXi provides two routes to the Jan. 1, 2020, ADS-B Out mandate. Its twin WAAS GPS receivers and standard operating system generate the extended squitter message set required for ADS-B Out. The standard twin GTX 335R remote Mode S ES transponders transmit the ADS-B set and they’re compatible with the Garmin GTS 820/825 traffic awareness systems or the Garmin GTS 850/855 TCAS I/ACAS I. For aircraft upgraded with Garmin’s optional GTS 8000 TCAS II system, Garmin offers the GTX 3000, a hybrid ADS-B/TCAS II/ACAS II Mode S ES transponder.
ADS-B In can be provided by upgrading from the GTX 335R to GTX 345R that has both Mode S and UAT ADS-B In channels. For aircraft fitted with GTX 3000 transponders, ADS-B In requires installation of the Mode S ES/UAT GDL 88 dual data-link transceiver.
The G1000 NXi has already proved to be popular with original equipment manufacturers. Virtually all general aviation aircraft manufacturers with current models fitted with the G1000 have announced upgrades to NXi. It’s also being offered as a retrofit for the King Air 200, 300 and 350, including those already having older G1000 retrofit systems.
Flying Impressions
We strapped into the left seat of Garmin’s King Air 350 with Scott Frye, manager of integrated flight deck retrofit programs, in the right seat for a brief demo of the G1000 NXi. Our route would take us from San Diego-Montgomery-Gibbs Executive Airport to Parker, California, then back to the San Diego area for approaches at Carlsbad’s McClellan-Palomar Airport and El Cajon’s Gillespie Field before returning to Montgomery-Gibbs.
The G1000 NXi retrofit for the King Air slashes empty weight by up to 250 lb., resulting in the ability to carry an extra passenger with full fuel or fly 125 nm farther with maximum payload. Three displays dominate the instrument panel. Similar to the Citation Mustang’s, there are left and right 10.4-in. PFDs and a central 15-in. MFD. The large MFD allows a full two-column stack of engine instruments on the left side with plenty of room for a moving map on the remainder of the screen. The retrofit package has stand-alone left and right audio control panels that provide one-touch, top-level access to all radios, an audio recorder and the entertainment system. There is a flight guidance system mode control panel mounted below the center of the glareshield. Between the left PFD and MFD, there is a vertically mounted Mid-Continent Instruments Standby Attitude Module with an emergency battery.
The King Air retrofit mixes traditional Beech components with high-tech equipment from Garmin. The left side of the cockpit retains the decades-old Beech fuel control panel and analog quantity gauges. There is no CAS display on the EFIS. Stand-alone annunciator light panels are mounted in the glareshield and below the MFD.
As soon as we turned on the power, the improvements in the next-gen G1000 soon appeared. The displays have the same 1,024-by-768 resolution as the original G1000 screens, but they’re brighter and easier to read in the bright San Diego winter sunshine. The branding flash screens quickly timed out as built-in tests were complete. The boot-up process was considerably quicker than with the original G1000 system, such as the ones with which we’ve flown in the Citation Mustang, TBM 900 and Embraer Phenom 100, among other aircraft.
Creating new flight plans is considerably different than it is with first-gen G1000 systems, Frye explained. The origin and destination airports first are entered into designated fields, along with the active runway for each landing facility. That’s different from the original G1000. It required entry of all waypoints, including airports, into the body of the flight plan.
However, designating the departure airport and active runway enables SurfaceWatch to outline the selected runway with a cyan border to make it easy to identify on the MFD’s airport diagram. The diagram also shows the aircraft’s position on the surface and all taxiways with their names. From the Gibbs Flying Service ramp, for instance, we could see Runway 28R clearly outlined, along with all runway incursion hotspots, plus Taxiways J, H and A that we would use to get to the threshold. Once ADS-B is implemented fully, SurfaceWatch will show the proximate positions of other aircraft and vehicles on the airport surface.
Building the innards of the flight plan is a straightforward process. Typically, it starts by entering an anchor point waypoint for an airway or jet route, as applicable. Then, the airway or jet route is entered by name, followed by the transition or exit point. Published departure procedures and transitions can be added later, as provided by Clearance Delivery.
Approaching the destination, an arrival procedure and transition fix may be added as directed by ATC. Depending upon ATIS information, the active runway at the destination airport may require changing. Similar to entering runway data for the departure airport, entering the active runway for the destination airport enables high-level SurfaceWatch functions, including alerting the crew if the selected runway is too short.
Most flight-planning chores can be accomplished using the Garmin Pilot application for Apple iPads and iPhones, then uploading the plan using the G1000 NXi’s optional Connext Wi-Fi/Bluetooth data links. While that capability was not yet available in Garmin’s King Air 350, we previously explored its features in Garmin’s hangar at New Century Airport in Olathe, Kansas.
The Pilot app is easier to use than Tyson Weihs’ ForeFlight or Hilton Goldstein’s WingX Pro, in our opinion. But it lacks some of the competitors’ features, such as the ability to add an instrument approach to the flight plan. Its trump card is its full interoperability with Garmin flight decks equipped with the dual-band Flight Stream 510 Wi-Fi/Bluetooth transceiver. Do all the heavy lifting for flight planning at home and then just upload it once you’re in the cockpit. It also retrieves worldwide weather data, including NEXRAD, satellite and winds/temperatures aloft images and the full range of text products, plus TFRs. You can also use the Pilot app to file flight plans.
The Pilot app may be used to download FMS navigation databases and upload them to the G1000 NXi using Flight Stream 510. Once airborne, the Pilot app enables the crew to use it as an EFB hosting paperless charts, display NEXRAD radar imagery or even serve as a backup PFD, complete with synthetic vision. But we recommend making sure the cockpit also has USB charging ports for the tablets.
The Pilot app also is handy for passengers aboard aircraft with Flight Stream 510 and the G1000 NXi. They can use it to listen to Sirius XM satellite radio music from the avionics system and monitor aircraft progress along the flight plan route, including watching developing weather patterns.
After engine start, we taxied to Runway 28R. Make a note. As with virtually all first-generation synthetic vision systems, the Garmin PFDs make it appear as though you’re taxiing through tall grass rather than keeping on the centerlines of the pavement. Adding buildings, obstacles and topography, including taxiways, signage and hot spots are opportunities for growth in this SVS’s capabilities.
Once all those King Air prop governor and auto-feather checks were complete, we called for takeoff and headed for Parker VOR via Julian and Thermal. Once level in the mid-20s, we had time to explore some of the system’s new features. Frye showed us the G1000 NXi’s new HSI map overlays, including GWX 70 or Sirius XM weather data, traffic, lightning, relative terrain or topography. As some of these features are buried two or three, or even four, levels down in submenus, it’s best to explore them during prolonged high-altitude cruise or when chocked in the hangar and connected to ground power.
Missing from the system is the choice of HSI 360-deg. rose or 120-deg. arc presentations; full HSI compass rose-only is available. We’d like to see an arc/rose choice function added and we’d like to see it available as a top-level, one-touch switch.
We also explored the Electronic Stability and Protection (ESP) functions that help prevent inadvertent attitude, angle of attack (AOA) and redline airspeed/Mach limit excursions. If, for instance, the pilot exceeds 45 deg. angle of bank, ESP engages to nudge the aircraft back to a 30-deg. bank angle at which point it disengages. Once ESP engages at 45-deg. bank angle, the force with which it helps roll the aircraft back to 30 deg. increases all the way to 75 deg. At that point, the autopilot roll engagement limit is reached and the system disengages. ESP is disabled when the aircraft is below 200 ft. AGL or when the autopilot is engaged.
ESP also engages at predetermined pitch limits. For the King Air, it’s set at 20-deg. nose up and 17-deg. nose down. It nudges the nose up at Vmo or Mmo and pushes it down if the aircraft approaches stalling angle of attack. The AOA protection feature is required for coupled go-around.
Next, we headed to McClellan-Palomar Airport to fly the RNAV (RNP) Y Runway 24 procedure that offers 200-ft. ceiling — 0.75-mi. minimums. We were cleared direct to the ZASOG IAF. There are a series of step-down fixes prior to the LPV glidepath intercept that would give us an opportunity to sample the system’s vertical navigation capabilities.
But a late descent clearance clouded our ability to see how well the VNAV function works despite the prevailing clear weather. Eventually, we captured the 245-deg. inbound course and 3.3-deg. LPV glidepath at the final approach fix and let autopilot fly the procedure.
Just above minimums, we touched the go-around button, added power and configured the aircraft for the missed approach. Air traffic control constraints, though, prevented us from flying the full MAP, including entering the holding pattern about 5 mi. west of the shoreline.
Next, we headed east to fly the Localizer D approach to Runway 27R at El Cajon’s Gillespie Field. The 269-deg. inbound course is aligned with the runway centerline, but high terrain just east of the airport requires a 6.88-deg. plunge from the last fix to the runway. The steep descent exceeds FAA TERPs limits for straight-in approaches, so only circling minima are published.
So, for vertical guidance, we opted to use the visual approach function built into the system. But the only glidepath angle available is 3 deg. We intentionally chose this mode to illustrate the precautions that must be taken when selecting it.
As we approached within 6 mi. of the airport, the PFD’s synthetic vision cautioned us about the areas of CFIT risk as we descended to within 1,000 ft. of terrain ahead by displaying the proximate terrain contours in yellow. At 5 mi., we had descended within 100 ft. of terrain ahead, so SVS displayed those high risk areas in red. When we approached closely to the terrain ahead, we received TAWS aural alerts and warnings.
The takeaway from the exercise was clear. If pilots opt to use the 3-deg. visual approach mode, they must verify that the approach path is free of terrain and obstacle hazards.
We executed a go-around at the TAWS alert and returned to Montgomery-Gibbs for the ILS Runway 28R approach and landing.
Post-Flight Takeaway
The G1000 NXi approaches the capabilities of Garmin’s top-line G3000 and G5000 systems, having greatly improved display brightness and robust graphics processing, plus several upmarket features such as dual-band connectivity with iPads running the Garmin Pilot app, Iridium satcom weather, voice and text messaging, and flight logging.
The next-gen G1000 system provides virtually all the tools needed to enhance situational awareness, reduce pilot workload and warn pilots about traffic, terrain and weather hazards.
Its GFC 700 autopilot is one of the smoothest and most precise with which we’ve flown. It’s capable of flying virtually any type of straight-in instrument approach. ESP, along with autopilot coupled go-around capability, is a strong safety enhancement for single-pilot IFR operations. The next-gen G1000’s terrain, traffic and weather avoidance technologies are impressive. Garmin’s 40-watt, solid-state GWX 70 weather radar is a worthwhile optional upgrade, especially as it can be ordered with Doppler turbulence detection and ground clutter suppression.
But there’s still room for improvement in two key areas, in our opinion. We believe the synthetic vision system would benefit from the inclusion of a 3-D airport view, similar to Gulfstream’s PlaneView aboard the G500 and G600. As noted, we also believe it needs one-touch, top-level access to HSI rose and arc displays. And we’d like to see an adjustable glidepath angle for visual approaches.
Convenience and subordinate features abound, redefining what general aviation pilots expect from their avionics systems. No longer do they only want to use such systems for attitude, heading and performance monitoring, along with position, navigation, communication and surveillance functions. Thus, the G1000 NXi has far more features and functions than traditional avionics systems installed in high-end turbine aircraft.
The G1000 NXi gives general aviation pilots plenty of extras they enjoy, including music, air-to-ground voice connectivity and text messaging, trip odometers, maximum ground-speed records, Ac-U-Kwik airport directory access and even oil change reminders. And they can store individualized pilot profiles so that the avionics system remembers the user’s preferences, just as occurs in high-end luxury cars.
If the G1000 NXi were adapted for automotive uses, automakers likely would disable certain nonessential features while the vehicle is in motion. That would be especially critical to safe operation considering some menus are four layers deep.
But the G1000 NXi has no such restrictions in aircraft. Nonessentials are not grayed out when the aircraft is in motion, when it’s not in stable cruise or when it’s approaching the destination airport. It’s up to the crew to decide when and where it’s safe to explore and use such features. This is a sophisticated system that demands cockpit discipline and crew resource management to keep focused on the time-proven, safety-of-flight priorities of aviate, navigate and communicate.
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