Garmin G300 Systems Description for Cessna 162 SkyCatcher

Immediately below the route data, Regardless of the screen set-up, one screen or two, the G300 provides the pilot with the same information. The two-screen system differs in presentation thanks to display space twice as large. Garmin’s G300 Continued from page 69 avionics news • january 2010 71 avionics news • january 2010 71 the single-screen G300 displays engine information. A graphic ana- log and digital tachometer is on the left, complete with green arc and redline arc. To the right of the tach, one above the other, are oil pressure and temperature — both depicted as horizontal bar graphs with a floating needle and digital readout. Next to it are a carburetor tempera- ture gauge and an ammeter employ- ing the same display format as the oil gauges. On the far right, is a trim indicator. Together, the flight-plan and engine-information sectors take about one-fifth of the screen space vertically. Next on the display, and taking up half of what remains, is the PFD and its wealth of information. On the PFD, the air data is split on the left and right sides, with the left getting a vertical indicated air- speed indicator with a magnifying window at the center; marks for flap and stall speeds appear on the inside of the vertical bar, and green, white and red segments make up the vertical bar between the num- bers display and the limit markers. Above the airspeed indicator, a window shows groundspeed while a corresponding window below shows true airspeed. On the right side, altitude and vertical speed appear, again with a magnifying window at the center. The altitude tape also sports a bug that can be set to the desired alti- tude. On the vertical-speed tape, the needle moves vertically with col- ored bars extending from zero to the needle. Above the altimeter readout, a window displays the altitude setting from the altitude bug, while another window below shows the altimeter setting. Between these two air-data dis- plays, the screen sports the combina- tion attitude indicator, compass head- ing, bank-angle indicator and, at the bottom, a horizontal slip/skid ball. On the remaining display space below the PFD’s two-fifths of a screen, the MFD maps and controls appear, along with a 120-degree-arc DG and, along the bottom, the indication of the chosen functions of the soft keys. Continued on following page 72 avionics news • january 2010 The pilot uses the soft keys to access maps and weather pages, change the layout of the PFD, and for control of the display of engine information, XM radio and terrain avoidance functions. It sounds like a lot to cram into a small space, but Garmin’s layout covers the needs without making it seem overly cluttered or confusing. Dual-Screen Version: So Much More The two-screen system naturally airs out the depictions considerably, giving every item more space to play. But there are some differences. For example, the flight-plan data at the top on the single-screen stays at the top of the dual-screen’s PFD; however, the same route information and the engine-information displays move to the right to top off the MFD. The PFD’s AI graphics and all the air-data readouts get slightly more space and remain in the same orienta- tion as on the single-screen version. But the gyro-compass display on the dual-screen system gets the entire lower half of the screen, along with a HSI-type CDI needle and indicators, including the heading bug. The lower half also provides room for four windows, one in each cor- ner of the HSI/DG depiction, with heading in the upper left, course in the upper right, local time in the lower right and OAT in the lower left. A separate window displays wind information, both velocity and approximate direction. On the MFD are the engine and route data and a near-full-screen map — with all the page functions a pilot needs: terrain, weather and maps, as well as access to the flight- planning pages and airport informa- tion available in the database. Special Modes: Just in Case If the MFD of a dual-screen G300 fails, the PFD side reverts to look like the same screen in a single- display G300 system, but with one functional rescission: the satellite- based functions become unavailable because the receiver is part of the failed box; therefore, no WxWorks weather or XM radio. If the PFD side fails, the remain- ing MFD screen does double duty and appears as the single-screen system; however, with the XM func- tions retained. This set-up allows the G300 to retain all of its critical functions and continue to provide information regardless of which dis- play remains, with the XM functions as the only real loss Although both GDUs sport their own WAAS/GPS engines, the G300 cannot provide full navigational redundancy because the GPS anten- na connects only to the PFD in a dual-screen installation. In the SkyCatcher, the GPS is the only navigation system available; there is no VHF navigation avail- able. Beyond its navigation role, the dual-screen G300’s PFD needs GPS input to provide valid attitude infor- mation should either air data or magnetometer inputs fail. Failure of air data has no effect on the AHRS output as long as the AHRS receives valid GPS data. If GPS, airspeed or magnetom- eter fail, the system provides an appropriate flag warning of heading or heading and attitude failure or position-data failure. If the GPS alone fails, the AHRS can continue to provide attitude and heading information as long as air- speed and magnetometer data con- tinue. Using the System As Garmin systems go, the G300 seems more user-friendly in its inter- face than prior systems of my sam- pling — not surprisingly, it shares some characteristics with the G1000 and G600. Garmin’s G300 Continued from page 71 The G300’s overall package, installation, integration and operation more than fulfill the need for a modern trainer set up as an entry point into more sophisticated aircraft and avionics packages — and it does it well. avionics news • january 2010 73 The system starts simply enough, whether dual or single screen: with a click of the Sky Catcher’s mas- ter switch. The G300 begins to sequence through its initialization process; the AHRS starts to align; and the GDU checks its database types and operating dates before prompting the pilot to continue. The system prompts the pilot to keep wings level, but the AHRS can align itself while taxiing or in level flight — helpful in the event of a power failure requiring a breaker to be reset. Once the AHRS aligns and the systems check is complete, the pilot pushes the “Enter” button to con- tinue. The system operates pretty much automatically and autono- mously aside from pilot input for flight plans, screen choices and the like. The pilot can flight-plan and acti- vate the plan using the G300’s inte- gral database of airports, airport information, airways and navies. The pilot can select a map dis- play showing terrain elevation rela- tive to the aircraft’s altitude or one showing the weather overlaying an IFR-type map or on the VFR screen. The pilot also can set a heading bug from the PFD — the twist-knob function of the joystick defaults to the “Heading” function. The soft keys at the bottom can provide for setting either the baro- metric pressure or an altitude bug. When either heading or altitude bugs are set, the PFD shows the selected heading above the AI and on the HSI. The heading and alti- tude bugs both serve a function as settings or references, with or with- out the autopilot. Set an altitude bug, and the altim- eter heading shows the selected alti- tude and a flag appears alongside the selected altitude and works its way to the center, where it high- lights the altitude when reached. The G300 provides an excellent vertical-navigation mode as well, using a pilot-set arrival altitude, air- port elevation data, a pre-selected descent rate, and the aircraft’s alti- tude and position data. When the time arrives to begin a descent at the selected rate, a glide slope-like indicator appears to the left of the altimeter scale and shows how closely the descent rate match- es up with the needed rate. Additionally, the engine data on either single- or dual-screen installations can be switched on or off with alarms still appearing as required. A nice fuel-flow function and precise exhaust gas temperature gauge make easy work of leaning for maximum fuel efficiency. The G300’s terrain and obstacle databases also inform an active alert system that flags “Obstacle” or “Terrain” when the aircraft flies to near or too low. The obstruction flag on the PFD is accompanied by a box showing the location of the obstacle on the MFD; the terrain flag appears when the aircraft drops below 1,000 above the ground out- side an airport area. Both warnings first show up as yellow flags, then red if the threat becomes more imminent. Another useful feature of the G300 is its ability to look up fre- quencies for an airport or ATC facil- ity on the appropriate page, high- light it with the cursor, then load it directly into the standby position of the SL 40 VHF com radio. The system also provides a page for selecting channels to listen to with the XM satellite radio service. Because this is not a FAR 23 air- plane or a TSO’d product, the radio does not have to mute each time the com radio breaks its squelch or someone speaks over the intercom. In a Nutshell: G300 Covers the Bases As a category, the light-sport air- craft (LSA) was created to provide a lower-cost aircraft alternative to the FAR 23 hardware for both pilots and sport pilot license holders. While Cessna equipped the SkyCatcher for day and night VFR work, the sport pilot is restricted to day-only VFR flying, and the G300 system in the SkyCatcher reflects this focus. The GPS provides ample naviga- tion power and accuracy, particu- larly when coupled with the G300’s power blend of airport, airways, navigation, terrain and obstacle databases. The single- and dual- screen installations offer an excel- lent entry into the dominant world of EFIS cockpits and integrated panels. The G300’s overall package, installation, integration and opera- tion more than fulfill the need for a modern trainer set up as an entry point into more sophisticated air- craft and avionics packages — and it does it well. The worst thing it might do — spoil a new pilot for flying anything other than an EFIS panel — likely is not a problem for Garmin or Cessna. q If you have comments or questions about this article, send e-mails to avionicsnews@aea.net.