Download - MVAs and AIXM
MVAs and AIXM
Dr. Navin Vembar
The CNA Corporation
AIXM5 in the Real World
Outline
• What are MVAs and MIAs?
• Modernizing the MVA and MIA Process
• The MVA/MIA Model
• Moving Forward
Outline
• What are MVAs and MIAs?
• Modernizing the MVA and MIA Process
• The MVA/MIA Model
• Moving Forward
What are MVAs and MIAs?
• Minimum Vectoring Altitudes and Minimum Instrument Altitudes– Used to ensure that aircraft avoid obstacles and
terrain
• MVA used by TRACONs with ARSR radar– Each radar has its own MVA chart
• MIAs used by facilities with ASR radars– Usually ARTCCs or large TRACONs
• Need to automate for safety reasons
How Areas are Built
• Each MVA or MIA area is constructed from polygon “modules”– Many areas have
holes in them to avoid particular obstacles or terrain points
• Picture on the right is from the SDAT tool
Outline
• What are MVAs and MIAs?
• Modernizing the MVA and MIA Process
• The MVA/MIA Model
• Moving Forward
The Process, As-Is
• Facilities design their charts– Use sectional charts for obstacle and terrain
information
• They submit the chart by paper to the National Flight Procedures Office– Fill out relevant forms including information about
the controlling obstacles or terrain for each area
– NFPO can reject or accept the chart
– Done yearly
The Modern MVA Lifecycle
RVM, ACES
Design (SDAT) Submit
Flight Procedures (NFPO) Validation
Implement
New obstacle review (using
NASR and OE/AAA)
Concept of Operations
RVMACES
RVMACES
Store (NASR)
SDAT For Automation
• The Sector Design and Analysis Tool (SDAT) is the cornerstone of MVA/MIA modernization
• SDAT allows designers to create MVA and MIA areas– Validates against digitized obstacles– Validates against USGS NED data for terrain– Computes necessary polygon mathematics
(buffering, adding, subtracting)
SDAT For Automation
• SDAT is a tool that has existed since 1998– Currently version 5.12
• Uses AIXM 3.3 for representation of MVA and MIA data– But, we’re talking about AIXM5!
• After approval, the SDAT backend will– Convert to AIXM 5 – Submit to the National Airspace Resources
(NASR) Repository
Outline
• What are MVAs and MIAs?
• Modernizing the MVA and MIA Process
• The MVA/MIA Model
• Moving Forward
Data Model for MVAs
Airspace(from Airspace)
<<feature>>
Unit(from Organisation)
<<feature>>ResponsibleParty
<<datatype>>M
MinimumAlti tudeAreas<<feature>>
Point(from Geometry)
<<object>>
MinimumInstrumentAlti tudeAreas<<feature>>
MinimumVectorAlti tudeAreas<<feature>>
MinimumAltitudeAreaList<<object>>
VerticalStructure(from Obstacle)
<<feature>>
ElevatedPoint(from Geometry)
<<object>>MinimumAltitudeArea
<<feature>>
1
hasUnit
1
1hasDesigner
1
0..*hasApprover 0..*
1
hasRadarLocation
1
1
hasAreas
1 1
hasAreas
1
0..n0..n
1
hasControll ingObstacle
1
hasHighTerrainPointNoBuffer
hasHighTerrainPoint
What Are We Leveraging?
• AIXM 5 Features & Objects– Feature Collections– Airspace– Unit– (Upcoming) Services– ResponsibleParty
Feature Collections
• Key to the whole process
• MVA Charts are features which contain MVA Areas, which are again features
• Solution: Feature Collections
• Features can be aggregated into a larger feature known as a feature collection
Other Features
• Unit – Representing facility information
• Service– Representing facility radar
• The key is reuse– Why model something already done for you?– Attributes and elements are optional, only fill
in what you need
Conversion
• Problem: SDAT creates data in AIXM 3.3
• We want to move to AIXM 5 for new web service and exchange communications– Tool of choice: XSLT– Difficulties
• Different GML models for representing geometries• Converting between DMS and decimal degrees
Implementation Choices
• Now that we have the model, what about implementation?– How to represent aggregate geometries within
an Airspace?• GML+xlink is very flexible and thus brings up this
question
– How much of the dependent feature and object data do we need?
Implementation Questions
• How to implement model while storing and disseminating?– What will be efficient?– What will be useful?
• Model and implementation are separate issues– Consider users and the level of flexibility required
• Persistence Web Server– MVA/MIA: Only one “user”, so specification of implementation
can be limited
• General consumers– Can use any implementation that meets the model
requirements
Implementation - Storage
• Efficient?– As we may reuse modules across different areas,
store those once• Provides spatial value as when the AIXM is moved to Oracle
SDO, these may be indexed separately
• Useful?– We are reusing nodes, but we never manipulate them
• Implementation– Consists of a list modules– Areas use xlink and Airspace aggregation to refer to
the modules
Implementation - Editing
• Efficient?– Again, use shared modules
• Useful?– Now, a user may move a single node and have it
affect multiple areas– Requires node-level data
• Implementation– Consists of a list of nodes– Build modules from nodes using xlink references– Areas use xlink and Airspace aggregation to refer to
the modules
Outline
• What are MVAs and MIAs?
• Modernizing the MVA and MIA Process
• The MVA/MIA Model
• Moving Forward
Plans
• Using Web Services– “Black Boxing” MVA and MIA data
• Achieved decoupling
– Will be used in obstacle proposal process
• Persistence of AIXM data– Using Oracle 11’s GML handling to convert
directly to SDO
Conclusion
• AIXM 5 is contributing to a successful implementation of MVA and MIA storage and dissemination
• Gaining leverage from its components– AIXM 5 features– GML– XML
Questions?