ARINC Meteorological Data Collection System: Enhancing Aviation Weather Forecasts

1. ARINC Meteorological Data Collection and Reporting System (MDCRS)Communications Segment of NOAA’s AMDAR Program January 14, 2007

2. Introduction to ARINC • ARINC has provided information and communications services for the airlines and others since 1929. • We operate one of the most flexible and sophisticated private networks in the world to ensure mission-critical communications for more than 700 transportation industry companies and government agencies, including: • Approximately 100 airlines worldwide • FAA and National Weather Service • For the commercial aviation industry, we provide a global air/ground communications network with voice and data services for airline operations control and air traffic control. • Headquarters in Annapolis, MD, with offices and facilities to serve customers in 140 countries.

3. Communications Management Unit (CMU) • Air Traffic Services Unit (ATSU) • AIMS • Aircraft router • AOA Aircraft Conditioning Monitoring System CMU/ATSU/AIMS Printer Multi-functional Cockpit Display Unit VHF Data Radio (VDR) Flight Management System Central Maintenance Computer • VHF Digital Radio (VDR) • Digital, multimode radio • Voice: 25 kHz, 8.33 kHz • Data: ACARS, VDL/AOA-ATN VHF Antenna Air-Ground Communications Services • Airlines use VHF air/ground data link service to communicate air traffic control, airline operational control, and airline administrative control between ground-based organizations and the cockpit.

4. Air-Ground Communications Services • HF/VHF Voice • VHF Data Link ACARS/VDLM2 • SATCOM • HF Data Link (HFDL) Virtual 100% assurance of message delivery

5. Typical Data Link Applications Aircraft Communications Addressing and Reporting System (ACARS) Taxi From Aircraft Link test/clock Update Fuel/crew information Delay reports Out To Aircraft PDC ATIS Weight & balance Airport analysis V-speeds flight Plan-hard copy Load FMC Departure From Aircraft Engine data Ascent Weather reports To Aircraft Flight plan Updated weather En route From Aircraft Position reports Weather reports Delay info/ETA Voice request Engine info Maintenance info To Aircraft ATC oceanic clearances Weather reports Re-clearances Ground voice request (SELCAL) Take-off From Aircraft Off Approach From Aircraft Provisioning Gate requests ETA Special requests Engine info Maintenance infoDescent Weather reports To Aircraft Gate assignments Connecting gates Passenger & crew ATIS Landing From Aircraft On Taxi From Aircraft In Fuel info Crew info Fault data (from central maintenance computer)

6. History of MDCRS • In late 1980s the concept of an automated aircraft reporting system for collecting weather observations was developed. • FAA and NWS funded implementation and operation of the Meteorological Data Collection and Reporting Service (MDCRS). • ARINC fielded MDCRS in 1991 • 3 Participating airlines; Delta, Northwest, United • American, FedEx, and UPS participation added. • Southwest joined in 2005. • ARINC has continually provided the service under contract with the FAA.

7. Importance of MDCRS • MDCRS is an important data sources for aviation weather forecasts. • Data show temperature inversions that forecast ceiling and visibility at airports in the LA basin. • Useful in forecasting wind gusts & LLWS in terminal areas. • Used in RUC model for aviation forecasts. • Benefits to the airlines • Accurate wind forecasts enable efficient routing and fuel savings • Greater predictability of weather hazards • Improved forecasting of local conditions, freezing levels, icing, phases of precipitation, wind shear profiles and turbulence, potential for fog. • More accurate forecasts of temperature, wind, clouds, and storms. MDCRS has become an extremely useful data source enabling a significantly better understanding of atmospheric conditions. (American Meteorological Society, Feb. 2003)

8. Airline Participation • Today’s numbers • 7 participating airlines • American, Delta, FedEx, Northwest, United, UPS, Southwest • 1500 aircraft report Winds and Temps • 60 UAL a/c report Turbulence (EDR) • 25 UPS 757s report Water Vapor • >100,000 observations per day, >3M per month. High resolution 3-D meteorological data from commercial aircraft have been shown to improve the accuracy of forecast, from short term (1 hour or less) to 1 week time projections.

9. Airline Participation – No. of Observations • 3,291,986 Observations from 1,462 aircraft – June 2006

10. Content of Typical MDCRS Messages • ACARS Header info contains Aircraft ID, Departure Station, Destination Station. • Time of Observation – Day, Hour, Minute (6 char.) • Latitude in Deg, Min, Tenths (6 char.) • Longitude in Deg, Min, Tenths (7 char.) • Pressure Altitude, feet (4 char.) • Wind Direction (3 char.) • Wind Speed (3 char.) • Static Air Temperature – degrees C (4 char.) • Roll Angle Flag (1 char.) • Phase of Flight (when available) (4 char.) • Turbulence (when available) (4 or 5 char.) • Icing (when available) (4 char.) • Water Vapor Mixing Ratio (when available) (4 char.)

11. Computers Airline NADIN II BUFR Messages MDCRS Data Processing by ARINC ACARS ARINC Data Network Service NOAA/OAR RUC Dev NOAA/OAR ESRL/GSD NOAA/OAR AMDAR Page Central Processor NOAA/NWS NCEP ARINC Packet Network NOAA/NWS“Gateway” BUFR NOAA/NWS NOAAPORT Messages ACARS GTS • Remove message headers • Extract raw wx data, validate format • Remove airline and flight IDs • Convert to binary (BUFR) format MDCRS Server

12. More than 100,000 Observations per Day • Some regions provide few observations and some provide more than are necessary. • Adding aircraft to improve coverage in data-sparse regions will increase data overall. • 86% of soundings come from 51 airports; 13 airports account for 31% of soundings. • NOAA Objective - Minimum 1 sounding/2 hours from 100 geographically dispersed airports.

13. Optimization Concept • NOAA desires a minimum of 1 sounding every 2 hours from 100 geographically dispersed airports. • Model for implementing an optimization system • 2 soundings per hour from 25 major airports • 1 sounding per hour from 15 airports • 1 sounding every 2 hours from 60 smaller airports • 1,700 soundings per day from 100 airports (assuming 18 hours of operation each day). * Sounding collection tuned to more fully reach 100 airport/2 hour goal. * Better data coverage and cost effectiveness. • Enable selection of specific aircraft to provide only essential data to meet needs of forecasting agencies. • Reduce number of meteorological reports being transmitted from aircraft without degrading forecasting capabilities.

14. Top of Climb (TOC) Top of Descent (TOD) Taxi Take-Off Departure En Route Approach Land Taxi 60 sec interval to ON 6 sec interval to 90 secs from OFF 20 sec interval to 510 secs to TOC 3 min. interval to TOD Typical ARINC 620 Reporting 91 samples during a typical 2:15 flight • Aircraft must be able to accept commands from the ground to configure reporting.

15. Requirements of an Optimization System • Send uplink message in ARINC 620 format to enable or disable reporting from aircraft based on a/c departure or destination airport and scheduled time of departure of arrival. • Command reporting “On” for ascent, descent, en route, or for more than one phase of flight. • Accept pre-planned schedule from NOAA for an entire day. • Accept changes from NOAA to pre-planned schedule as often as once per hour. • Accept flight schedules from participating airlines. • Match airline flight number and aircraft tail number. • Assign higher or lower priority to aircraft based on reporting capabilities.

16. Summary • Commercial aircraft are an important source meteorological observations for NOAA through the MDCRS program. • U.S. airlines have been participating in MDCRS for 20 years. • Currently about 1,500 aircraft operated by 7 carriers provide over 100,000 observations a day. • While more data are received from many areas, some areas are not well covered. • More aircraft can be added. • Optimization systems can be used to select aircraft and flights that provide the most useful data and potentially more cost effective.