1

Introduction to Categorical Amendment Criteria (CAC)

Joe JureckaAviation Program Leader NWS Lubbock, TX Commercial Pilot ASMEL Instrument

SAWS IIIPhoenix, AZ23 Mar 2010

2

Contributors

Cammye Sims, Aviation Services BranchBrad Sipperley, WFO Fairbanks, AKAaron Tyburski, WFO State College, PADavid Hotz, WFO Morristown, TNJoe Dellicarpini, WFO Boston, MATodd Lericos, WFO Caribou, ME

3

Presentation Outline

Why change? Review of Standard Amendment Criteria CAC Methodology, Thresholds, and Limitations Amendments Using CAC Benefits of Using CAC Implementation

• To provide the aviation community with a more responsive product tailored to their regulatory needs

• A more concise productis possible when theforecast is tailored toaeronautical decisionsand impacts.

Why make a change?

Standard Amendment Criteria

Review ofStandard Amendment Criteria

Standard TAF Amendment Criteria

Impacts of Standard Amendment Criteria

• Non-standard individual airport minimums ignoredOnly 200 feet and 1/2SM used (CAT I ILS)Airfields served only by non-precision

approaches are not represented

7

Impacts of Standard Amendment Criteria

• Aviation community receives too many amendments that do not have an impact on airport operations

• Forecaster time is diverted from sites/tasks needing attention

• TEMPO groups may restrict operations resulting in flight delays and impacts the National Airspace System (NAS)

8

CAC Methodology, Thresholds, and

Limitations

CAC Methodology, Thresholds, and Limitations

Employs the following important concepts:Ceiling and Visibility meet specific airport

requirementsGroup Ceiling and Visibility together into

categories to match FAA RegulationsTEMPO groups checked immediately against

METARS to notify forecasters of resulting customer impacts

10

Methodology

TAF Amendment Current

TAF Amendment Break Down the Wall

TAF Amendment CAC

ATC FLOW

PRECISION NON-PRECISION

Customized Airport Minimums

• Airport minimums tailored and grouped together to meet specific airport requirements

• Eliminates unnecessary or non applicable amendments

• Example: Airport minimums 400’ AND 1SM (not standard 200’ AND/OR 1/2SM)

• Eliminates need for amendments once ceiling or visibility falls below 400’ and 1SM

• Also applies to alternate minimums14

• WFOs have the ability to meet the special needs of the airport or local Air Traffic Management with additional amendment criteriaExamples

• Phoenix Sky Harbor (KPHX)– Visual approaches: Minimum ceiling of 5000’

• Boston Logan Airport (KBOS)– Circling approaches: Minimum ceiling of 1400’ and

visibility of 3SM

• Increased service to our customersThese are new, customer-driven thresholds only available using CAC

15

CAC Local Thresholds

CAC Limitations

Example: KLBB - Runway 17R Category A Minimum:

200’ and 1/2SM- Runway 35 Category A Minimum:

600’ and ¾ SM

• CAC uses the lowest airport minimums, which are 200’ and 1/2SM

Only addresses categories for ceiling and visibility

Does not include wind or RVRThresholds are not “runway specific”

• Limited to one value for each category at each airport

• Categorical Amendment Criteria:The lowest element of ceiling or visibility is

considered “controlling” for amendment purposes

• Standard Amendment Criteria:Software prompts for an amendment based on

ceiling OR visibility

17

CAC vs. Standard Amendment Criteria

• Better customer service amendments based upon specific airport criteria Regulatory needs of the flying community addressed Quicker response to customer needs, including out of category

TEMPO groups

• Forecaster’s time maximized Improved situational awareness Allows focus on sites needing attention amendments only issued for meaningful

thresholds• Fewer amendments

(WFO FAI decreased by 23%)• Comparable reduction seen in Lubbock

18

Benefits of Using CAC

19

WFOs using CAC as of April 2010

Fairbanks, AK

• Notify Users well ahead of transition date– Airlines– FBOs– ATC Facilities (TRACON/ARTCC/AFSS)– FAA Safety Team (delivery to GA community)

• Modify AVNFPS to display CATegory well in advance of transition date.

• Transition to CAC and remove CIG/VSBY from AvnFPS

• Follow-up with your aviation partners20

CAC Transition for NWS Offices

21

Questions???joe.jurecka@noaa.gov

Introduction to Categorical Amendment Criteria