Garmin GNS 530AW Supplementary Manual - Page 5

Browse online or download pdf Supplementary Manual for Marine GPS System Garmin GNS 530AW. Garmin GNS 530AW 12 pages. For continued airworthiness bell 206b
Also for Garmin GNS 530AW: Pilot's Manual Addendum (24 pages), Pilot's Manual Addendum (50 pages), Pilot's Manual Addendum (24 pages), Quick Reference (23 pages), Quick Reference (25 pages), Instructions Manual (23 pages)

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Detailed Description of Feature Changes

1. TSO

TSO C-129/C-129a allowed the use of GPS for

supplemental navigation for non-precision approaches.

An installation meeting TSO-146a requirements allows

the use of your 400W/500W navigators as the primary

navigation device for precision approaches.

See your dealer for detailed information about how the

new TSO affects the operation of your aircraft.

2. WAAS Capable

WAAS (Wide Area Augmentation System) is a

system to provide improved integrity and accuracy of

GPS signals used for navigation. "Wide Area" refers to

a network of ground reference stations that cover the

entire U.S. and some of Canada and Mexico. Imple-

mented by the FAA (Federal Aviation Administration)

for aviation users, these reference stations are located

at precisely surveyed spots and compare GPS distance

measurements to known values. Each reference station is

linked to a master station, which puts together a correc-

tion message and broadcasts it via satellite. The corrected

differential message is then broadcast through one of two

geostationary satellites. The information is compatible

with the basic GPS signal structure, which means any

WAAS-enabled GPS receiver can read the signal. WAAS

capable receivers typically have accuracies of one meter

horizontally and 2 meters vertically.

Basically, it' s a system of satellites and ground sta-

tions that provide GPS signal corrections, giving you

even better position accuracy. How much better? Try

an average of up to five times better. A WAAS-capable

receiver can give you a position accuracy of better than

two meters 95 percent of the time. And you don't have to

purchase additional receiving equipment or pay service

fees to utilize WAAS. WAAS also provides the capabil-

ity of quickly determining when signals from a given

satellite are wrong and removing that satellite from the

navigation solution.

The Federal Aviation Administration (FAA) and the

Department of Transportation (DOT) are developing

the WAAS program for use in precision IFR approaches.

Without WAAS, GPS alone does not meet the FAA' s

navigation requirements for accuracy, integrity, and

availability. WAAS corrects for GPS signal errors caused

by ionospheric disturbances, timing, and satellite orbit

errors, and it provides vital near real-time integrity infor-

mation regarding the health of each GPS satellite.

Currently, WAAS satellite coverage is only available

in North America. There are no ground reference sta-

tions in South America, so even though GPS users there

can receive WAAS, the signal has not been corrected

and thus would not improve the accuracy of their unit.

For some users in the U.S., the position of the WAAS

satellites over the equator makes it difficult to receive

the signals when trees or mountains obstruct the view of

the horizon. WAAS signal reception is ideal for aviation

applications. Your Garmin 400W/500W series system

provides for primary GPS navigation in areas where no

WAAS coverage is available using a Fault Detection and

Exclusion (FDE) RAIM algorithm.

Other governments are developing similar Satellite-

Based Augmentation Systems (SBAS). In Asia, it' s the

Japanese Multi-Functional Satellite Augmentation System

(MSAS), while Europe has the Euro Geostationary Navi-

gation Overlay Service (EGNOS). Once these systems

are fully tested and operational, your 400W/500W series

system will be capable of using these systems.