Garmin International Inc., a unit of Garmin Ltd. said it has been granted the Federal Aviation Administration’s (FAA) first ever approved model list supplemental type certificate (AML-STC) for Wide Area Augmentation System (WAAS) avionics installed in a helicopter.


The AML-STC is for the installation of the Garmin GNS 400W/500W series and includes approval for IFR flight and steep approach lateral-precision with vertical (LPV) guidance. With this comprehensive AML-STC, GNS 400W/500W series units may be installed in approximately 50 different makes and models of helicopters including the Bell 206, Enstrom 280FX, Agusta A109, Eurocopter EC135, MD Helicopters 600N-NOTAR, Robinson R22 and R44 and many more.

“Receiving an STC for a single helicopter is an impressive feat, but to receive an AML-STC for approximately 50 helicopters is an accomplishment many thought would never happen because of the complexity and differences between helicopter models,” said Gary Kelley, Garmin’s vice president of marketing. “We are very pleased that this AML-STC will make it easier for operators of the world’s most popular helicopters to install the GNS 400W/500W series. These pilots will now have access to the unmatched technological advantages and safety enhancements that come with a fully integrated GPS/WAAS product.”

The GNS 400W/500W series received the FAA’s highest level of certification for WAAS navigation. The units utilize satellite-based navaids for precise lateral and vertical approach guidance – similar to Instrument Landing System (ILS) operations – without the need for ground-based navaids of any kind. The FAA has already published over 1,500 LPV and 5,600 LNAV and LNAV/VNAV approach procedures, which exceeds the number of ILS approaches.


The WAAS system improves the accuracy, reliability and integrity of the GPS signal. GPS-WAAS navigators that meet the FAA’s WAAS regulations may be used for sole means of navigation for all phases of flight, including en route through precision approach at airports and heliports – wherever they may be. With WAAS LPV approaches, pilots will have stabilized lateral and vertical navigation, and will be able to navigate as low as 200 feet above the touch down point under instrument flight rules.


As part of the IFR certification, the GNS 400W/500W series is also certified for custom steep LPV approaches for up to six degrees, flying by hand or with a fully coupled autopilot. These custom approaches help law enforcement and medical teams land in areas with urban rooftops, such as hospitals, in the most extreme weather conditions and below public en route minimums.


“Using customized steep LPV approaches will ultimately help save lives because flight crews can increase the services they provide as they pick up patients in need of transport,” said Kell