GPS in Civil Aviation: Safety, Capacity, and Efficiency

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GPS in Civil Aviation Safety, Capacity, and
Efficiency

• Captain Rocky Stone
• Chief Technical Pilot
• United Airlines

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What does GPS do for civil aviation?

• Space-based navigation allows more aircraft in
  our airspace
• Guarantee of a 27-30 satellite constellation will
  reduce en-route and terminal spacing
• GPS will reduce fuel burn and greenhouse gas
  emissions
• More direct, time-based routings
• GPS Timing better precision operations
• GPS Surveillance for safer and more efficient
  operations due to position awareness
• Reduced runway incursions
• Provides greater situational awareness
• Increased capacity with increased safety

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NextGen is GPS!

• RNAV/RNP
• VNAV
• EFB
• FANS/Data Communications
• GBAS/LAAS
• WAAS
• ADS-B
• CDTI
• Curved Path - Approaches
• Surface Traffic Applications
• ASDE-X, RAAS, TIS

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NextGen GPS dependency

• RNAV/RNP - GPS
• VNAV - GPS
• EFB - GPS
• FANS/Data Communications - GPS
• GBAS/LAAS - GPS
• WAAS - GPS
• ADS-B - GPS
• CDTI - GPS
• Curved Path Approaches - GPS
• Surface Traffic Applications - GPS
• ASDE-X, RAAS, TIS

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ATL departure paths before RNAV
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ATL with RNAV accuracy!
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RNP Enables Lower Minimums
Slide courtesy of
Juneau
Procedure
Standard
Alaska Non-RNP
Alaska RNP
724/1
Runway 8 arrival
2,880/4
1,000/2
Day800/2 Night2,000/5
Day800/2 Night2,000/5
Runway 8 departure
RVR 1,600
RNP also enables increased maximum takeoff weight
Runway 26 arrival
None
None
337/1
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Slide courtesy of
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Juneau Approach
Video courtesy of
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Optimum Profile Descents are the future of all
approaches huge fuel savings!
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United has pioneered the use of Tailored
Arrivals Ex HNL-SFO Fuel Saved 1600 lbs!
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UAL Surface Moving Map Test
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RAAS SystemApproaching Runway - On Ground
44 of Runway Incursions in our study
involve loss of position awareness.

• Conditions for advisory
• Advisory depends on aircraft groundspeed, heading
  and nearest runway end
• Earlier call-out at higher speeds
• Inhibited above 40 knots
• No distraction during take-off/landing ground roll

Approaching One-One
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GPS based Terrain Awareness

• Using RNP enabled by GPS in the vicinity of high
  terrain increases safety margin and adds capacity
• Much better performance from the Terrain
  Awareness and Warning System (TAWS)
• No RADAR required!

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What is ADS-B?
ADS-B Enables Safety In the air and on the
ground

• Automatic
• Dependent
• Surveillance
• Broadcast

Surface / Terminal / En Route / Oceanic
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SFO Paired Approach Concept
Final Approach Path
RW28R
Collision Danger Area
Final Approach Path
RW28L
Trailing
Aircraft
No Wind
Window
Wake Vortex
Hazard Area
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ADS-B for Wake Vortex Avoidance

• Adding wake vortex avoidance information in ADS-B
  allows for ground based wake vortex capacity
  prediction systems and air-to-air wake vortex
  visualization systems
• Ground based system needs to accurately predict
  capacity at least two hours in advance
• Needed parameters
• Wind, Temperature, Aircraft Wake Vortex Category,
  Eddy Dissipation Rate, Flap setting

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Motivation for Wake Visualization
IFR vs. VFR Separation
FAA Regulated Separation Distances for IFR
Leader Aircraft
Follower Aircraft
Note Distance behind 757 is 4 nm for all
aircraft.
Distances in nautical miles
Slide courtesy Dr. J. David Powell, Stanford
University
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Wake Visualization Display
Picture courtesy Dr. J. David Powell, Stanford
University
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How does GPS benefit civil aviation?

• Precision Navigation MORE CAPACITY, MORE ALL
  WEATHER OPS
• Reduced fuel burn
• Reduced block times
• Position Awareness SAFETY, INCREASED CAPACITY
• Precision Timing BETTER FLOW MANAGEMENT

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Thank you!