Citation Mustang cockpit evolving as G1000 arrives

 - February 1, 2007, 11:20 AM

No doubt many pilots have been asking themselves lately how Garmin has possibly managed to develop an integrated glass cockpit for the Cessna Citation Mustang business jet that will also fly aboard a variety of light piston singles. Can the avionics in a $2.3 million twinjet really be the cousin of an integrated avionics package that costs the same as the equipment it replaces in a Cessna Skylane? Or are the corporate bean-counters at Garmin using fuzzy math?

The answer has a lot to do with economies of scale and Garmin’s tremendous buying power in the consumer electronics and display industries. Last year the Olathe, Kan. company produced a dizzying two million individual products, spanning everything from handheld GPS receivers to car navigation equipment and even fish finders and personal digital assistants with integrated GPS cards. Building such a vast array of products meant Garmin first needed to purchase millions of circuit boards, computer chips and LCD screens. All came from suppliers that are thrilled to count the rapidly expanding avionics maker as a customer.

No manufacturer can come even close to matching Garmin’s enormous economies of scale in the avionics industry. Since the company introduced its popular GNS 430 and 530 all-in-one GPS/navcoms in the late 1990s, more than 41,000 have been sold worldwide. This means that the cost to build just one GNS 430 is amortized over many units, pushing production expenses down and spreading out R&D costs. Few avionics manufacturers can say they have sold 41,000 of anything over such a short period, especially a piece of equipment carrying retail prices between $9,000 and $15,000.

Think of Garmin’s feat in terms of the most basic of electronic gadgets–the pocket calculator. It would be difficult to produce calculators for under $50 a unit if the production run was small–say, 200 calculators in each run. But since the parts used to build calculators are purchased in such high volumes, consumers can buy a calculator for less than $5.

Now apply that thinking to avionics. To a degree, the economic theories at work here translate to the G1000 cockpit, which shares components and technology with the GNS 430/530 and uses glass displays from a variety of long-time Garmin suppliers. By building the G1000 using common display units, low-power Intel XScale processors, a standard Ethernet databus architecture and a low-cost attitude and heading reference system (AHRS), Garmin has been able to offer the G1000 to aircraft OEMs for less than its competitors, namely Avidyne and Honeywell.

Capturing the Imagination of GA
To date, the G1000 has been selected for the Diamond DA-40 and DA-42, as well as Cessna’s 182 and 206 singles and Mustang compact jet. It is also flying aboard the HondaJet, the six-passenger entry-level competitor from the Japanese carmaker that made its maiden flight in December. Garmin spokesman Pete Brumbaugh said that if market projections for the G1000 prove true, the cockpit has the potential of doubling the company’s avionics revenue in two years.

“Garmin is in an extremely strong cash position, and the G1000 has really captivated the imagination of general aviation,” he said. “There’s nothing really novel we’re doing with this cockpit. For the most part it is mature technology. But the G1000 system is scalable, and so it can just as easily go into piston airplanes or into jets.”
Considering that Cessna plans to build nearly 1,000 Mustangs before the decade is out, in addition to an untold number of piston singles fitted with the G1000, it appears the success that has followed the company since it was founded in 1989 by Gary Burrell and Min Kao (the Gar and Min in Garmin) will continue into the predictable future. The pair of former Bendix/King engineers correctly saw GPS as the revolutionizing technology, and together they have created a world-present company that is listed on the Nasdaq 100 and has a market value approaching $6 billion.

Diamond Aircraft will be the first to offer the new technology, in the DA-40 single. That cockpit boasts a pair of 10.4-inch flat-panel displays. The left display shows all primary-flight information and a multifunction display to the right is used for viewing engine and system data, as well as maps, weather, terrain and flight-plan information. A similar configuration is being tested aboard the Cessna singles, with certification of the packages expected within the next few months.

The cockpit in the Mustang, meanwhile, will feature a 15-inch multifunction flat-panel display in the center of the instrument panel flanked by a pair of 10.4-inch primary flight displays. Garmin is supplying the Mustang’s autopilot, FMS, weather radar, terrain awareness and warning system (TAWS), traffic information system (TIS), solid-state AHRS and air-data computers.

In competing for the Mustang cockpit, Garmin beat out Honeywell, Avidyne and Rockwell Collins, enticing Cessna with a combination of simplicity, quality and low price. The capabilities of the G1000 package convinced Cessna to pick the Garmin system over the Apex suite being offered by Honeywell Bendix/King, a move that surprised some industry observers–but not nearly as much as the announcement that the G1000 system was also destined for Cessna’s piston singles, which have flown for years with Bendix/King equipment.

The Mustang’s cockpit will include dual integrated radio modules, WAAS-capable IFR GPS receivers, RVSM-compliant air-data computers, mode-S transponders, dual AHRS, three-axis digital autopilot, weather radar and Garmin’s forthcoming class-B TAWS, said Bill Stone, Garmin’s avionics product manager. The airplane’s FMS will be built on the GNS 430/530 platform, but with enhancements, possibly including a traditional FMS keypad.

In the versions of the cockpit designed for pistons, there is an area on the bezel labeled FMS, but it includes only half a dozen keys and a knob. While this setup would probably be perfectly acceptable to the average weekend pilot flying with a pair of GNS 430s, in turbine-powered airplanes Garmin will need to offer something a bit more traditional. A standard alphanumeric FMS keyboard tied to the multifunction display would satisfy most any pilot who straps into the Mustang.

From Pointers to Pictures
Garmin has spent the money necessary to bring design expertise for the G1000 under its wing. Sequoia Instruments of Los Gatos, Calif., a Garmin subsidiary purchased in November 2001, developed the G1000’s low-cost AHRS, a key ingredient of the system. Garmin also bought an airborne weather radar design from Narco (a radar originally designed by Bendix/King) and hired a group of engineers to develop the Mustang’s automatic flight control system.

Garmin has been testing the autopilot design, the GFC 700, since last March in a Beech Baron 58P from Garmin’s test center at New Century Airport in Olathe. One unique feature of the GFC 700 is that all of its electronic controls are housed in the servos that move the flight controls, and not a central computer. These self-monitoring servos use brushless DC servomotors that are more expensive than traditional motors, but which have the benefit of being able to control their speed and torque electronically for more precise trim response and airspeed command. The motors are also claimed to be far more reliable than traditional equipment and, as an added bonus, they are nearly silent.

Brumbaugh said Garmin is well into testing of the three-axis automatic flight control system and expects initial certification in the second quarter. Obviously, OEM applications such as the Citation Mustang will be first for the autopilot, but Garmin also plans to explore aftermarket possibilities. This would likely be tied to a complete retrofit to the G1000 since the autopilot is being designed as an extension of the avionics, with a common architecture across all platforms from light singles to jets.

For steering clear of storms, Garmin’s airborne weather radar is a reengineered version of the KWX 58 radar known to pilots of older airplanes such as Learjets and King Airs. When Bendix/King long ago was forced to divest itself of the radar, Narco bought the design but never did anything with it. Brumbaugh said Garmin “picked up the radar for a song” and put its engineers to work making changes to the design.

From a mechanical standpoint the radar is the same as the KWX 58, but its electronics have been redone. The 28-volt radar system uses a 10-inch flat-plate antenna and weighs about 10 pounds. It is TSO’d to 50,000 feet and a maximum range of 320 nm. (Garmin is so pleased with the progress it has made on the design that it plans to offer a marine version of the radar.)

The G1000’s displays use thin-film transistor (TFT) technology, the latest innovation in LCD manufacturing. This provides wider viewing angles than flat-panel displays of the past, as well as good sunlight readability. The 1,024- by 768-pixel XGA displays communicate with each other over the Ethernet bus and use a graphics accelerator at a 30-Hz rate for high-performance 3-D rendering. The displays are fully self contained and measure only about two inches deep. Glass is supplied by NEC, Sharp and Samsung, with customized filming and backlighting added to the displays after initial manufacture.

For anyone who ever thought of glass panels as high-tech video games for the cockpit, they’ve never been closer to being right. The computing power represented by the G1000 would be the envy of most PC gamers and is more than required to allow for future upgrades. The G1000 needs to retain its high level of capability far longer than the typical home PC, and so Garmin has ensured there is room for growth.

The PFD and MFD in the piston airplanes are the same part number, meaning they are interchangeable in the event of a failure. If the PFD goes blank while flying, for example, the pilot can simply press a button and the MFD reverts to a primary display. What’s more, if the pilot was to land at an avionics shop and ask for a replacement display, the techs would simply slide in a new screen, tell the display what type of airplane it was in and the electronics would automatically begin configuring over the Ethernet bus.

The G1000 for the Mustang will have dual AHRS and air-data computers (RVSM compliant), which could obviate the need for conventional backup instrumentation. Avionics LRUs can be remotely mounted in the avionics bay or, as is the case in the Mustang and HondaJet, everything can be installed behind the instrument panel. This frees up space for baggage and gives mechanics easier access to the avionics and sensors, which can be worked on by simply removing four screws and pulling out the displays.

Future enhancements to the G1000 include the addition of a “perspective view” to the PFD that would portray terrain and nav information on the blue-over-brown artificial horizon. Brumbaugh said this synthetic view might be included in the DA-40’s avionics package later this year.

Flying the G1000
Garmin offered a demo of the G1000 system in the DA-40 and Cessna 182 from New Century Airport on December 18 (fittingly the first day of aviation’s new century). Flying first with Garmin chief test pilot Tom Carr in the DA-40, it quickly became apparent why GA pilots are so excited about the new avionics. The G1000’s big, bright displays are reminiscent of the latest avionics from Honeywell and Rockwell Collins that fly in multimillion-dollar business jets, yet the system retains the character of the GNS avionics with which so many pilots fly.

The G1000 PFD has a wide-view artificial horizon with V-bar indicator and an HSI in the pilot’s choice of arc mode or full display at bottom center. Vertical tapes to left and right of center read out airspeed and altitude, leaving plenty of room for a miniature moving map and a real-time nearest airport display. A number of soft keys on the bottom potion of the display are used for setting up the display and entering necessary data.

In the air, Carr demonstrated that the G1000’s AHRS does not need to remain stationary to configure itself, as is the case with other systems. After disabling the AHRS and entering both a series of shallow and 45-degree-bank turns to the left and right, the AHRS reinitialized itself within about 30 seconds. Next Carr demonstrated the ease with which flight plans and instrument approaches can be entered into the G1000’s FMS (which for now is connected to a Bendix/King KAP 140 two-axis autopilot). For any pilot proficient with the GNS 430/530, flight planning should be no problem.

In the 182 Skylane, Cessna flight ops pilot Bryan Drayton demonstrated the autopilot’s ability to capture approach courses from difficult angles and showed off the unusual-attitude-recovery cues on the PFD.

Training will be an issue for pilots transitioning to tape-style readouts from traditional flight instruments. Brumbaugh said Garmin provides a “pre-delivery kit” to buyers that contains an interactive DVD and a free-play simulator. The company is also in the process of developing training curricula for flight schools and plans to begin working with a full-flight simulator manufacturer soon to develop the Mustang sim.

At the heart of the G1000 is the GIA63 integrated avionics unit, essentially a GNS 430 that talks to the rest of the avionics over the high-speed databus. Garmin is also developing an XM Radio weather datalink receiver that will provide not only the ability to track storms anywhere in the U.S., but also about 100 channels of CD-quality audio. Other developments in the works are the TIS traffic and class-B TAWS, which should be certified later this year.