6a supp

Item No. 6a_supp 
Meeting Date September 12, 2017 
Ground Based Augmentation
System (GBAS) 

1

GBAS Location 
Location 




Seattle Tacoma International Airport Site Map 
2

GBAS System 


How it works 
3

Instrument Landing System (ILS) 
First installed in 1940 
ILS is a combination of
radio signals and
lighting systems that
provide horizontal and
vertical guidance. 
DC-3's carried 75% of passengers in 1940 
Instrument Landing System History 
4

Why GBAS? Why Now? 
A proven technology. 
Existing Instrument Landing System is affected by objects
in close proximity, GBAS does not have this limitation. 
Aircraft increasingly come equipped with GBAS Landing
System technology. 
Airlines want GBAS. 
FAA Air Traffic Control Tower endorses GBAS installation. 
Free upgrade by Honeywell leverages the Port's investment. 
Future environmental benefits. 
Keep current with technology 
5

Limitations of Translatable Documents

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