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 RVM ACES RVM ACES 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

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?