Garmin Enhances Helicopter Navcoms
Garmin’s touchscreen GTN series GPS/navcoms have been optimized for helicopters. The avionics units come in five configurations that meet vibration and temperature testing standards and offer optional NVG compatibility and optional H-Taws.

Garmin’s touchscreen GTN series GPS/navcoms have been optimized for helicopters, with new features that eliminate the need for operators to install the fixed-wing GTN version in helicopters. The new helicopter-optimized GTN comes in five configurations that meet vibration and temperature testing standards and offer optional NVG compatibility and optional H-Taws.

New helicopter-specific features include three databases: obstacles, with about 30,000 additional low-altitude obstacles; terrain, with 2.5-arc second terrain resolution, which “improves terrain alerting by reducing nuisance alerts when operating at low levels,” according to Garmin; and 7,000 additional heliports. The new GTN is available with built-in H-Taws, featuring selectable voice callouts at 100-foot intervals when descending from 500 to 100 feet agl. Another H-Taws feature is Garmin’s Reduced Protection mode, which “allows low-level operations with minimal alerting while continuing to provide terrain and obstacle protection.” H-Taws provides visual alerts, too, and five-color terrain scale. The GTN series offer an optional radar altimeter input; Garmin’s new GRA 5500 can supply that data (see below).

Installation of Garmin GTX 32/33/33D remote transponders allows pilots to control the transponder from the touchscreen GTN. ADS-B OUT-capable versions of those transponders are also available. Garmin’s new GMA 35 remote mount audio processer can also interface with the GTN 750 units, and pilots can use Garmin’s Telligence speech recognition system to control some audio panel functions. Installers can add remote switches on the collective and cyclic for functions such as fly-over mark-on-target waypoints or remote frequency tuning.

The helicopter GTN series have received FAA TSO approval for hardware and software. Prices start at $10,935, and the units will be available later this month. Garmin is developing STCs for installation of the GTN series in a variety of helicopters.

Last month, Garmin (Booth No. N4412) unveiled its new GRA 5500 radar altimeter. The GRA 5500 already holds FAA TSO approval and is available immediately at a retail price of $13,995 (without antenna). The GRA 5500 is an all-digital design that employs digital signal processing technology. The GRA 5500 communicates over a standard Arinc 429 interface, allowing the radar altimeter to work on a variety of Garmin integrated flight decks and displays and third-party products.

According to Garmin, the new digital technology allows the GRA 5500 “to provide smooth altitude tracking resulting in a consistent and highly accurate altitude above ground indication, even over the most challenging environments like rough terrain, tree canopies, sand and choppy water.” Digital technology, including application of digital filters, enables the GRA 5500 to process hundreds of altitude measurements per second “to help detect and mitigate false altitude returns.” The GRA 5500 includes built-in self-test monitors that “continuously cross check the data and system integrity, assuring the pilot of an accurate measurement of the height above ground,” according to Garmin.

In January, Garmin introduced the new GTR (com) and GNC (navcom) series radios, which are available for Part 27 helicopters as well as fixed-wing airplanes. The new radios offer 8.33-kHz frequency spacing, more transmitter power and built-in frequency databases and replace the SL 30 and 40 models.

Features include a frequency database, which helps pilots find frequencies associated with an airport or facility by entering location name or station ID. Confirmation of the correct frequency is aided by the reverse lookup function, which shows the navaid or airport ID when manually tuning a frequency. The GTR/GNC radios also offer a nearest function, for airports, area control centers, flight service stations, weather frequencies and VORs.

All of the new radios include a voice-activated two-place intercom; storage of 20 most frequently used frequencies and up to 15 pilot-selectable frequencies; flip-flop for entering frequencies in a standby window; and a com monitor function. The GNC navcoms add VOR and ILS with glideslope and can display nav indicators on Garmin G500/600, G500H and G3X systems.