Gulfstream IV and V series aircraft remain two of the most capable lines of business jets designed in the past three decades because of their range, speed and cabin comfort. The GIV can fly 4,200 nm and the GV can fly 6,500 nm. Both aircraft routinely cruise at Mach 0.80 or faster and they can seat up to 12 to 14 passengers.

The GIV and GV are equipped with Honeywell SPZ-8000 series avionics systems that were cutting edge when introduced in the late 20th century. But back then, augmented GPS was in its infancy, the airspace was considerably less congested, paperless cockpits were mere science projects and uplinked weather graphics were pipe dreams. And CRT displays were cutting edge.

Fast forward to the 21st century. At the beginning of the new millennium, it became clear to Gulfstream Aerospace, among other OEMs, that older aircraft equipped with this generation of Honeywell avionics would need comprehensive cockpit display, FMS and radio upgrades to operate efficiently in the future.

PlaneDeck is Gulfstream's trade name for its Honeywell Primus Elite flat-panel display retrofit for SPZ-8000, -8400 and -8500 avionics suites. A six-pack of 8-by-8-in. DU-885 AMLCDs, which fit into the same mounting racks, replaces the original half dozen DU-880 CRTs. Additional wiring and connectors, though, are needed to connect the displays to new left and right cursor control devices mounted in the cockpit side ledges, to a new USB thumb drive/SanDisk data loader and to an XM satellite radio weather receiver.

Each flat-panel display has its own internal graphics processors and database that enables it to host specific functions when plugged into a specific rack in the panel. At present, display units 2 and 5, which function as left and right navigation displays (NDs), can host Jeppesen electronic charts, enhanced map graphics with XM radio weather overlays and video provided by on-aircraft visible light or infrared EVS cameras.

Swapping out the CRTs for LCDs has other benefits. The LCDs consume so much less power that they have double the expected life and don't require external cooling fans or air filters that must be changed. The LCD boxes also aren't prone to CRT phosphor screen burn-in, so they don't have to be rotated around the panel every 100 hr. to assure even wear characteristics. So, if you do trade an LCD PFD for an LCD ND, the navigation display won't have ghost images of an attitude indicator, air data tapes and a compass rose.

Each DU-885 LCD weighs about 7 lb. less than a DU-880 CRT, plus there's a weight savings from removing the external cooling fans and ducts. Gulfstream officials say overall weight reduction is close to 50 lb.

PlaneDeck isn't inexpensive, being priced at $725,000. But it's Gulfstream's own conversion program, downtime is only 10 days, it's fully supported by the OEM in the aftermarket and it's available through ASC-476A for GIV/IV-SP/G300/G400 aircraft and through ASC-183A for GV airplanes.

FMS 6.1 is sold separately from PlaneDeck and it's the second and equally valuable part of Gulfstream's avionics upgrade program for GIV and GV series aircraft. It's a hardware and software upgrade for the stand-alone NZ-2000 nav computer boxes and CD-820 MCDUs. (Early GIV aircraft were equipped with NZ-800 FMS boxes. They need to be swapped out for NZ-2000 computers to be eligible for FMS 6.1.) It's available as ASC-477 for GIV series aircraft and ASC-186A for the GV family. FMS 6.1 is priced at $153,000 for dual FMS and $171,000 for triple FMS. Installation time is 15 days, mainly due to the need to swap out GPS receivers and antennae for WAAS GPS equipment.

Generically, Honeywell's FMS 6.1 upgrade offers three key provisions — satellite-based augmentation system (SBAS) GPS/localizer performance with vertical guidance (LPV) approach, Future Air Navigation System (FANS) provisions and required navigation performance (RNP) functionality.

Gulfstream's current version includes a WAAS/LPV approach capability. That provides ILS look-alike guidance to more than 3,340 runways in the U.S., including more than 2,240 that don't have ILS. Notably, Canada now has more than 80 SBAS LPV procedures and Europe has more than 75 EGNOS-based LPVs.

The FANS functions are more limited, more works in progress. Aboard GIV and GV aircraft, FMS 6.1 installs provisions to accommodate controller to pilot data link communications (CPDLC), automatic dependent surveillance — contract (ADS-C) for transoceanic operations and air traffic services facilities notification, essentially the initial communications handshake between aircraft and ATC that's required before either CPDLC or ADS-C can be activated.

For FANS, the MCDU CD-820 control display units also must be upgraded with new faces having an “ATC” button to provide access to CPDLC functions.

FMS 6.1 includes an RNP with 0.3-nm accuracy function. But it cannot yet be used to fly RNP Authorization Required approaches. That will require certification of the FMS, aircraft flight guidance system and autopilot as an integrated system capable of flying with RNP 0.3 precision. One prime reason is that GIV and GV aircraft are not yet certified to fly radius to fix legs, curved segments that are used to construct many RNP AR approach procedures.

The NZ-2000 upgrade also adds circling approaches to the navigation database, a vector to final feature, temperature compensation for cold weather baro VNAV and full vertical navigation, plus automatic hold to altitude, heading to altitude and heading to intercept functions, along with supporting multiple approaches to the same runway, TACAN approaches for Defense Department operators and database cross-loading between FMS boxes.

Make a note. If you're using the FMS to fly down to circling minimums, you'll still have to hand fly the aircraft, or use the flight guidance system's heading and altitude hold modes, to maneuver inside the protected circling airspace and position the aircraft for the final landing approach.

Let’s Go Flying

On Gulfstream's ramp at Savannah/Hilton Head International Airport, we belted into the left seat of GIV-SP serial number 1297, an immaculately restored 1996 model that has both the PlaneDeck and FMS 6.1 upgrades, along with new paint and comprehensive interior refurbishing, plus the Honeywell 36-150 APU upgrade that greatly increases bleed air supply for heating, air-conditioning and engine starting.

Gulfstream's Ron Newton, senior experimental test pilot, occupied the right seat and Kristian Wollan, senior captain for ACP Jets, which manages and charters the aircraft, flew along in the jump seat as safety pilot, advisor and videographer.

Newton explained that all six DU-885 LCDs have the graphics processing, Jeppesen chart database and enhanced map graphics to support PlaneDeck functions, including XM satellite radio weather graphics. Plugging in the display units to the DU 2 and 5 racks, corresponding to the left and right navigation displays, activates all currently available PlaneDeck functions on those two displays.

If one of the six DUs were to fail, the aircraft still can be dispatched with the remaining five displays. But the advanced PlaneDeck functionality is lost because the basic displays are needed to support legacy reversion functions.

Newton says he normally leaves one ND in the legacy display mode, even if all six are operating. He then uses the cross-side ND for advanced PlaneDeck features in flight. The legacy map mode, for instance, has a wind vector display, but the advanced map function does not yet offer those data.

Serial number 1297 also is equipped with an optional Elbit Systems Kollsman general aviation vision system (GAViS), an uncooled IR camera mounted in the top of the radome. IR imagery is displayed on either the left or right ND. GAViS is quite useful for augmenting situational awareness at night or in reduced visibility. But it's not approved as an enhanced flight vision system that can be used for credit to fly down to lower weather minimums in accordance with FAR Part 91.175.

PlaneDeck's video display function also can support external or internal cameras, an approved IR EVS camera and/or Airshow maps, if such equipment is installed aboard the aircraft.

The combination of the PlaneDeck LCDs and FMS 6.1 makes it possible to use the FMS CDU to call up Jeppesen charts on the NDs for the original, destination and alternate airports in the flight plan. Without FMS 6.1, airports must be selected using a virtual keyboard and the cursor control device. We found that process to be awkward at best.

Initialization of the charts function takes about 30 sec. because of the volume of data that must be loaded into memory from storage. The database contains airport, SID, STAR, approach, noise, NOTAM and special-use airspace charts for the entire world. The actual geographic coverage area that can be displayed depends upon an individual's Jeppesen subscription.

Wollan commented that when he flies internationally, he just calls Jeppesen to activate electronic chart subscription for the specific area in which he's flying. Jeppesen provides a product key that the crew enters into PlaneDeck to unlock the coverage. The whole process takes less than an hour.

After initialization, once the origin, destination or alternate airport has been selected with the FMS CDU, a drop-down menu appears on the ND that lists all the available charts for the airport. Departing Savannah, for instance, we clicked on the geo-referenced taxi chart hot link. The airport diagram popped up and a green airplane symbol appeared on the screen, depicting the aircraft's position and heading. The taxi diagram was quite useful for orientation with the airport layout and as an active map while taxiing to Runway 28 for takeoff.

Newton commented that PlaneDeck's electronic chart function has all the redundancy required for Class III paperless cockpit certification. Wollan, though, still uses an iPad with electronic charts as a backup because the whole chart can be displayed in a relatively large size.

Viewing the entire chart with PlaneDeck is difficult at times because of the display's comparatively small screen. So the system has a split screen function that shows the chart graphic in one block plus either the chart header, minimums block or remarks section in a second block. Using the cursor control device, it's possible to zoom in and make part of the image or text larger and easier to see.

While taxiing, we called up the maps function. It, too, takes about 30 sec. to load because of the volume of data. Airports, VORs, NDBs, intersections, high and low altitude airways, and special-use airspace can be called up. Temporary Flight Restriction boundaries will be added in the future.

Weather products include NEXRAD radar, storm tops, satellite imagery, winds aloft, AIRMETs and SIGMETs, clear air turbulence and lightning. We selected special-use airspace, airports and VORs for display, along with NEXRAD weather and winds aloft charts. Care must be taken not to clutter the screen with excess data, but that's true for any current-generation moving map system.

After takeoff, we headed east to W-157A to spend some time exploring PlaneDeck's other map and weather display functions. Newton demonstrated the replay function that allows a sequence of NEXRAD images to be animated. We also looked at winds aloft graphic forecasts for several altitudes. Newton pointed out that he's used the system to deviate around areas of stiff headwinds, resulting in significant time, fuel and cost savings. We used the enhanced map special-use airspace boundary depictions to remain inside W-157A and fly well clear of the AR15/17/21 jetway that runs through the warning area.

We then headed back to Savannah to fly a couple of WAAS LPV approaches to Runway 28. We chose to display the RNAV (GPS) Z Runway 28 on the right ND and GAViS video on the left ND at Wollan's suggestion. Once we neared the airport, a green airplane symbol appeared on the geo-referenced approach chart, providing excellent situational awareness. Switching the right-side ND to the legacy moving map mode, we also could view our position in relation to the approach waypoints and course lines but without the richness of data supplied by the Jeppesen electronic chart.

Once we cleared approach, we arm–ed the system for LPV procedure. Gulfstream aircraft, fitted with original SPZ-8X00 avionics systems, display long-range navigation guidance data in cyan and short-range guidance in green. Even though WAAS LPV is GPS based, the FMS automatically switched from cyan to green at course intercept. Newton said that it was easier to adapt the flight guidance system for LPV approaches by mimicking ILS inputs, so the green short-range nav color convention was retained.

The WAAS LPV approach guidance was indeed ILS-like in its smoothness and precision. Notably, the WAAS GPS signals are not subject to the kind of ground plane interference that can make following an ILS glideslope at some airports feel like you're flying in mountain wave.

The GAViS video also proved valuable during the approach. We could see the thermal signature of the runway pavement in contrast to the vegetation surrounding the field. At night, it would have proved even more valuable because it detects the thermal signature of incandescent runway approach lights, as well as the IR plume of jet engine exhausts, well beyond visual range in murky weather.

We landed after the second approach and taxied back to Gulfstream's ramp.

Conclusions

PlaneDeck and FMS 6.1 add considerable value to GIV and GV aircraft, even though these aircraft don't have Gulfstream's current PlaneView cockpit capabilities. XM satellite radio weather graphics enable pilots to make strategic flight planning decisions that boost safety margins and add operational efficiency. Situational awareness is much better because of the enhanced map graphics, electronic charts and video capabilities.

Adding WAAS LPV, along with circling approach and temperature compensated baro VNAV, plus several ARINC 424 procedure legs, such as vectors to final, heading to altitude, heading to course intercept and auto hold to altitude, provide valuable navigation enhancements. The TACAN approach capabilities should be popular with military and special mission operators.

However, it's the growth potential for PlaneDeck and FMS 6.1 that are most interesting. DU 1 and 6, the display units used for left and right PFD, are slated for a synthetic vision upgrade in the future. This also would be an ideal point to incorporate Honeywell's head-down display imagery that mimics HUD symbology, including adding a flight path vector and an EVS display window in the PFD that's one-to-one conformal with the SVS background imagery. Honeywell officials believe they can use head-down displays with flight path vector symbology and enhanced flight vision system IR imagery to gain credit to fly down to lower weather minimums in accordance with the requirements of FAR Part 91.175.

RNP authorization required approach guidance certification also is on the roadmap. FMS 6.1 positions SPZ-8X00-equipped aircraft for upcoming ADS and CPDLC requirements, including Link 2000+ in Europe. Rockwell Collins plans modifications to GIV and GV TDR-94S transponders that will enable them to support hybrid TCAS II/ADS-B IN (Do-260B) functions.

Gulfstream's ongoing investment in these aircraft is evidence that they have decades of potential service life remaining. Third-party firms, such as Clay Lacy Aviation, Universal Avionics and Duncan Aviation, also offer avionics upgrades to extend the useful lives of these venerable large-cabin aircraft. Gulfstream officials, though, say the firm's ability to integrate the PlaneDeck and FMS 6.1 upgrades into existing SPZ-8000, -8400 and -8500 cockpits and back them with full factory support provides a competitive advantage over outsiders.

The full support of FlightSafety International is another key advantage for the Gulfstream solutions. FSI already is making available to customers Level C and D GIV and GV simulators fitted with PlaneDeck DU-885 displays and FMS 6.1 capabilities. This will be a boon to flight crews who fly with aircraft having either or both of these upgrades.

PlaneDeck and FMS 6.1 together require an investment of $900,000+. But they also add to the aircraft's residual value in the resale market. GIV series aircraft command $8 million to $12 million and GV airplanes go for $15 million to $22 million, according to Penton's Aircraft Bluebook — Price Digest. Historically, factory support upgrades have returned up to 50% of their investment.

Regardless of resale value, GIV and GV aircraft remain two of the most capable large-cabin business aircraft families yet built. Upgrading them with PlaneDeck and FMS 6.1 assures that they'll be valuable air transportation assets for several years to come.