1. Previous radar-intensive, multi-aircraft programs (incl. TOGA-COARE, MAP, BAMEX) serve as useful models Key considerations: Identify communications pathways, including associated hardware/software requirements Refinement of planned tracks to integrate Doppler, in situ and dropsonde observations Give simultaneous attention to flight safety (platform separation, dropsonde releases at safe distance from lower-level aircraft) -and- efficiency in meeting RAINEX scientific objectives In-flight Aircraft Coordination and Communications for RAINEX

2. BAMEX* Communications Overview (*Bow Echo & MCV Experiment, St. Louis/MidAmerica Airport, 20 May – 6 July 2003)

3. VHF Radio Subject to line-of-sight + ‘P-static’ interference limitations Primary conduit for flightdeck-to-flightdeck communications, navigator coordination etc. Backup route for scientific coms (VHF1/VHF2); useful for more extended discussions between/ among chief scientists Communications Pathways

4. Digital Data bursts via satcom RAINEX will require periodic (ideally automated) transmission of aircraft locations and selected in situ quantities AC locations at 1 min resolution desirable for ingest into Zebra and generation of track plots Presumably requires medium-bandwidth (e.g. GlobalStar 9600 baud or better) pathway vs. ASDL Ops Center integrates data from existing operational pathways (e.g., NHC dropsonde relay) with specialized RAINEX data (e.g., track info + non-QC’d flight-level data) Communications Pathways

5. Interactive Text Messaging (e.g., IRC Chat) Requires continuous satcom PPP connection Supports rapid platform/mission status updates, efficient and accurate exchange of waypoints Conduit for Ops Center input to airborne science team re: mission strategies, contingency plans etc. Communications Pathways

6. Image Files Key data sources include GOES satellite imagery and lower-fuselage (LF) surveillance radar maps from lead NOAA P-3 Critical to rapid assessment/response to both initial and evolving eyewall + rainband structure Following download of LF data from lead P-3, Ops Center integrates multiple-platform track history, LF and/or satellite data, then re- distributes retrospective view + proposed tracks Bandwidth limitations require careful attention to geographical scope and resolution of imagery Communications Pathways

7. Communications Priorities/Limitations  Lead NOAA P-3 executing Module-2 (eyewall-penetrations) may track beyond VHF coms range limit w.r.t. Module-1 AC  Realistic turn-around times for LF download/re-distribution likely approach 30 min, during which precip patterns may both translate and evolve

8. Desirability of geometrically simple tracks (~straight-line or smoothly-varying curvilinear) for highest quality dual-Doppler sampling of rainbands Other Coordination Issues

9. Tightly-timed tracks (e.g. coordinated dual-AC “quad-Doppler”) bring special challenges Navigators, working closely w/ scientists, often pivotal in successful execution Coordination Issues (cont.)

10. 100 km 3 a/c mission NRL-black Piggy-white Kermit-blue GIV/C130-red

11. 100 km 2 a/c mission NRL-black Kermit-blue GIV/C130-red

12. Dropsonde Coordination Suggested tracks of GIV,C130

13. RSMAS C130/GIV NRL/P3 Kermit Piggy ATD NHC JOSS air ground Simplified RAINEX Data Flow HRD