King Air C90GTi, Pilot Training Manual

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SBAS is much more widely implemented. In the
US, over 2,000 runway ends are served by SBAS
approaches. The FAA has termed this as a Wide
Area Augmentation System (WAAS) because it
does not rely on airport specific towers to cor-
rect the signal and send the correction message.
Instead, it uses data from stations throughout
North America and a correction signal from geo-
stationary satellites. SBAS approved units are able
to receive correction messages from these satel-
lites and create a very accurate vertical and lat-
eral navigation unit. (See gps.faa.gov and the
Aeronautical Information Manual (AIM) for
more information).
Other countries will label SBAS differently when
it is implemented as shown in Figure 16A-1.
The Rockwell Collins FMS version 4.0 is the
unit needed to use the SBAS system in Collins
equipped aircraft. This FMS is used with a
SBAS capable receiver labeled GPS-4000S.
The FMS uses the corrected signal to create
appropriate vertical and lateral navigation dis-
plays during all phases of flight to include
WAAS approaches. SBAS and other software/
equipment upgrades are included with FMS
v4.0 and this addendum will highlight the
most critical. Refer to the appropriate Collins
FMS user guide,
AFM or AFM supplement for
a more complete listing of limitations.
The FMS v4.0 upgrade includes a new Flight
Management Computer (FMC) and proces-
sor. This allows for the increased rate of error
checking and position updates that occur dur-
ing WAAS flight and approaches. Additionally,
updating the FMS database should be faster
through the DBU-5000 since the communica-
tion speed has increased.
KING AIR 90 SERIES PILOT TRAINING MANUAL
16A
WIDE
AREA
AUGMENT
A
TION
SY
STEM
16A-2 FOR TRAINING PURPOSES ONLY
Figure 16A-1. Worldwide SBAS Providers