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UPS Airlines Use of AMDAR. Randy Baker 09 NOV 2011 UPS Airlines Senior Meteorologist. Why Did UPS get involved in AMDAR?. FOG: UPS operates into airports around the world within an hour or two of sunrise…the most likely time for operational impacts due to fog.
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UPS Airlines Use of AMDAR Randy Baker 09 NOV 2011 UPS Airlines Senior Meteorologist
Why Did UPS get involved in AMDAR? • FOG: UPS operates into airports around the world within an hour or two of sunrise…the most likely time for operational impacts due to fog. • Boundary layer temperature/wind/moisture is critical. • http://www.meted.ucar.edu/dlac/website/resources/upspaper.pdf
Fog Forecasting Example #1 • Moisture Increasing with Height • Inversion/Light Winds
Fog Forecasting Example #1 3 hours later… 0812z RVR 1000-2800FT 1254z RVR 600-1000FT
Example #2Fog Forecasting – SDF 29 Mar 05 Moisture decreasing with height Favors shallow ground fog
Fog Forecasting – SDF 29 Mar 05 AC#362 TYS->SDF starting at 29-Mar-2005 03:47:00 with 85 obs descent sounding ending at 29-Mar-2005 04:25:00 S F HHMM lat/lon Alt wd/ws t / td ( RH ) code 0 0 0421 38.0370/-85.7060 3300 338°/020 9.0/-1.10 (48.9%) 3930 2 0 0421 38.0150/-85.7030 3400 338°/020 8.6 0 0 0422 38.0600/-85.7150 2840 340°/022 10.3/-0.20 (47.9%) 4130 0 0 0422 38.0820/-85.7220 2400 339°/022 11.5/0.000 (45.0%) 4130 2 0 0423 38.1000/-85.7270 2040 331°/022 12.2/0.200 (43.5%) 4130 0 0 0424 38.1150/-85.7340 1710 324°/020 13.0/0.700 (42.8%) 4230 0 0 0424 38.1320/-85.7370 1360 328°/018 13.8/0.800 (41.1%) 4230 2 0 0425 38.1640/-85.7490 700 279°/003 11.5/4.700 (62.9%) 5430 0 0 0425 38.1720/-85.7510 580 130°/002 11.0/5.500 (68.9%) 5730 The First Descent report at 0425z confirmed the model forecasts of a sharp decrease in moisture with height. Furthermore, there was a 3C inversion with 18 knots of wind, indicating still mixy conditions, helping to mix the drier air down to the surface.
Fog Forecasting – SDF 29 Mar 05 • Earlier in the day rain had occurred (0.34”), followed by clearing late in the day. • Using the UPS Fog Forecasting method, the Crossover temperature was 8.3C, and with expected clear skies, calm winds, and a forecast low temperature of 4C, fog was of some concern. • Soil temperatures were on the warm side (9C), and BUFKIT ETA output showed good dry advection just off the surface until about 04z, followed by decoupling and possible fog conditions by around 07z. • Based on the model forecast of moisture decreasing with height, UPS meteorologists forecast ground fog with no operational impact at SDF where, due to runway construction, visibility below 3 miles would have caused significant delays to our Next Day Air inbounds.
Fog Forecasting – SDF 29 Mar 05 LOU (Louisville Bowman Field) did report 1/4 SM mile in ground fog, which was patchy across the city, especially in low-lying locations. SDF never dropped below a sector visibility of 2 1/2 SM. SDF 0356 00000KT 7SM MIFG CLR 08/07 A2978 REMRK A02VIS W 2 1/2 SLP084 T00780072 SDF 0456 00000KT 6SM MIFG CLR 07/07 A2979 REMRK AO2 SLP087 T00720067 401170067 SDF 0556 10003KT 4SM BR CLR 05/04 A2979 REMRK AO2 SLP090 T00500044 10106 20050 51012 SDF 0656 00000KT 5SM BR CLR 06/06 A2981 REMRK AO2 SLP096 T00560056 SDF 0756 00000KT 6SM BR CLR 05/04 A2982 REMRK AO2 SLP100 T00500044
UPS AMDAR History • UPS joined MDCRS program in early 1990s (automated reports every 510 seconds) • UPS deployed high rate Ascent/Descent report and added time-based option to ARINC 620 Specifications in Summer 1994. • UPS deployed first water vapor sensor 1996 (thinned film capacitor – measured RH) • UPS deployed laser diode water vapor sensors in 2004 – measured water vapor mixing ratio
UPS AMDAR History (cont’d) • Most recent water vapor sensor installed in 2009 with excellent results. Added Petersen encoding scheme. • UPS currently has 25 water vapor sensors installed on 757 aircraft. • UPS Fleets with routine AMDAR data: 757, 767, 747, MD-11 (167 total) • Automatically thin out KSDF hub Ascent/Descent reports and most International reports. Water Vapor data is not thinned at all.
UPS AMDAR History (cont’d) • Current Default Specifications • Ascent 1 every 6 seconds for 90 seconds • Ascent 2 every 20 seconds until 590 seconds have elapsed • Profile available on GSD website within 5-10 minutes • Enroute every 3 minutes; 5 reports transmitted in one report (every 15 minutes) • Descent Report every 30 seconds.
UPS AMDAR Lessons Learned • Programmable DFDAU (Digital Flight Data Acquisition Unit) allows UPS to make changes without significant additional cost. (Teledyne) • Pressure Altitude can be negative for stations near sea level with high surface pressures. • Wind information can be tricky…easy to reverse the sign of the N-S or E-W wind components, computing wind directions up to 180 degrees off. • Data bus 429 has a lot of similar information (such as position data), make sure you are getting the best possible information.
Recent GDL AMDAR Soundings RAOB GDL airport
UPS Use of AMDAR Data • Data used in operational forecasts • Fog forecasting (boundary layer moisture profile) • Thunderstorm forecasting • Southern California marine layer (low stratus/fog) • Winter storm precipitation type and timing. • Case study reviews of major weather events • Santa Ana Winds at KONT • Tropical Depression Ike at KSDF
Winter Precipitation Types SDF 15-16 Feb 2003
KSDF 151843Z 06015KT 2 1/2SM RA BR OVC013 01/M01 A3001 RMK AO2 RAB30 RAIN
METAR KSDF 160156Z 05009G17KT 5SM -PL BR OVC020 M01/M04 A3009 RMK AO2 FZDZE55PLB55 SLP192 P0001 T10111039 = FZRA, FZDZ, PL
KSDF 160556Z 04009KT 4SM -PL BR OVC018 M03/M04 A3006= KSDF 160456Z 04010KT 6SM -PL BR OVC020 M02/M04 A3007= ICE PELLETS
Santa Ana Winds • Causes Severe Cross-winds • Can prevent opening/closing cargo door • Wind events of 4-12 hours 30 gusting 60 knots • Strongest events are mountain waves
Mountain Wave Strongest Wind in and near Stable Layer
Jet Core East of ONT, Moderate to Strong Santa Ana event Mountain Wave
Tropopause Jet Tropopause Jet Stream Front Mountain Level – 10,000 Ft Ground Level BUR ONT PHX
Hurricane Ike Remnants • Previous Large Hurricane hit Texas coast near Galveston as a Category 2 storm 13 SEP 2008 • Downgraded to Tropical Depression in Arkansas 06z 14 SEP 2008 • Later that day, SDF was expecting Rain with winds 20-30 Knots. • Instead, SDF got 3 hours of winds 30 gusting 65 knots (tower 85 knots at 220 feet AGL). 70% of city without power. • SDF airport closed for several hours. • Region experienced $1 Billion damage,12 fatalities.
Data Quality Control IssuesTemperature Errors • 10% of our fleet have at least a +1C warm bias at all levels • 5% of our fleet have at least a +2C warm bias at all levels • At +3 to +4C Engine Condition Monitoring program detects possible TAT (total air temperature) errors. • Cause of errors: foreign objects (insect parts), lightning damage.
Data Quality Control IssuesPosition Errors • Some fleets used single inertial position information instead of combined position information (3 inertial systems plus any GPS/VOR updates). • As a result, some aircraft positions were in error, drifting at a rate of 1-5 nm per hour of flight time. • In process of changing data source to use FMC (flight management computer) best position information. Early 757s cannot be corrected at this time.
Data Quality Control IssuesWind Errors • Data bus provided instantaneous (4Hz?) wind information. • Turbulence can cause instantaneous changes in wind direction +/- 20 degrees and speed +/- 20 knots (continuous moderate chop). • Enroute reports going to 10 second averaging, Ascent/Descent reports going to 2 second averaging to minimize these wind errors.
Data Quality Control IssuesMoisture Errors • Early mixing ratio reports were coded with two significant digits. This resulted in loss of resolution going from 9.9 g/kg to 10, 11, 12, etc. Solution: Employed Petersen encoding scheme. • Air Sampler design can allow water from heavy rain (in flight) to flow into the unit, creating a moist bias until all moisture is flushed out. This can take several flight segments. • Air Sampler hoses can become blocked with foreign material, causing moisture readings to be nearly constant during all phases of flight.
Aircraft N411UP WVSS-II installation pictures at Goodrich during “C” check in May 2004. • Air Sampler (View looking inboard) • System Electronics Box (SEB) (View • looking outboard) • Air Sampler (View looking outboard)