1. AVAPS – Dropsonde HS3 2013 Field Program HS3 Science Meeting April 29-30, 2014 NCAR EOL ISF 2014 Terry Hock 1, Gary Wick 2, June Wang 1, Kate Young 1 1 National Center for Atmospheric Research 2 National Oceanic & Atmospheric Administration

2. AVAPS HS3 2014 Field Campaign Hurricane and Severe Storm Sentinel – HS3 NASA Global Hawk AV-6 – 433 Dropsondes – 7 Research Flights for AV-6 – Aug 20 to Sept 19, 2013 – Atlantic Ocean

3. HS3 Data Quality Issue# of soundings% of dataset Fast Falls (complete)214.8% Fast Falls (partial)71.6% No Temperature Data0- No RH Data0- Loss of data near surface due to RFI 81.8% Poor Winds at surface4510.4% Overall Success rate# of SoundingsSuccess rate Perfect Soundings, no issues35281.3% Useful scientific data - Includes Fast falls, RFI, GPS multipath 433100% HS3 2013 Sonde Performance Summary

4. Raw Wind Data Sept 5 Drop 20130905_041459 Horizontal winds GPS Vertical Velocity

5. Actions taken from HS3 2012 to HS3 2013 to Minimize RF Interference Change antenna coaxial cable between AVAPS system in Zone 16 to low loss double shielded coax, such as PIC S22089 (PIC Wire & Cable). Relocate the UHF aircraft blade antenna to the rear of the aircraft behind the zone 61 door hatch – Create a mounting plate such that the antenna mounting is approximately horizontal to flight to maintain good vertical polarization. 5

6. RF Spectral Plot HS3 2012 RF04 Sept 19, 2012 Time Flight Duration Frequency 400-406 MHz

7. RF Spectral Plot HS3 2013 RF07 Sept 19, 2012 Time Flight Duration Frequency 400-406 MHz

8. NSF/NCAR G-V RF Spectral Plots Time Flight Duration Frequency 400-406 MHz

9. Impact of Global Hawk banking during drop - HS3 2012 RF 04 Drop #10 Sonde release

10. Impact of Global Hawk banking during drop - HS3 2013 RF 07 Drop #13 Sonde release Sonde release Drop #14

11. 11 PTU Mean Vertical Resolution (meters) Wind Mean Vertical Resolution (meters)

12. 12 2012 2013

13. 13 2012 2013

14. HS3 2013 Dropsonde Data QC files updated 4/14/2014 Updated geo-potential height values in original QC’ed files released 12/20/2013 Contained negative geopotential heights at the surface Heights integrated from surface upward, rather than from aircraft downward. No other parameters were changed

15. HS3 2013 Global Hawk AVAPS