Airborne Gravimetry at the U.S. Naval Research Lab 1980-Present Mary Flather Peters Early History of NRL Airborne Program – Pre Kinematic GPS 1979 Preliminary Design of System First test of Early Prototype off Carolina Coast Jun-80 Loran C Nav RMS ~ 20 mGal 8 Flights Incorporation of GPS Nav and test off Wallops Island, VA Jun-81 RMS < 6 mGal 2 Flights 12 Flights, no Dec-83 Piggy Back Gravity on Airborne Magnetics Study East of Brazil ground truth Blind Test over Eastern NC for DMA Apr-84 Incorporation of Pressure Altimetry RMS 2.5 mGal 4 Flights 15 Flights, Data May-84 Piggy Back Gravity on Airborne Study of the Angola Basin not reduced 12 Flights, no Feb-86 NSF Funded Study of the Antarctic Margin, Airborne Gravity over Ice ground truth Eastern Seaboard Test for NSWC RMS Jun-86 Difference with NSWC Shipboard Data < 4 mGal 6 Flights Feb-87 NSF Study of Antarctic Margin Average Mis-tie 2.2 mGal 10 Flights Sep-87 NSWC Inteferometric GPS Test 6 Flights Oct-87 NSF Study of Antarctic Margin 9 Flights 1988-1989 Gravimeter, Altimeter and Computer upgrades Nov-89 NSWC/ NRL Interferometric GPS/INS tests 6 Flights Norwegian-Greenland Sea and Eurasia Basin Aeromag Profiles (1973-76) Canada and Eurasia Basin Aeromag Profiles (1972-83) P3-B (heavy) -154589 in Spitsbergen -1999 P3-A -149674, NRL Flt Sup. Det. 2nd P-3 Antarctic Geophysical Surveys Airborne Gravity, Magnetics and Surface Topo – P3, L&R − * 1985 – Rio Grande, Argentina – Weddell Sea (East of Ant Peninsula) − * 1986 – Punta Arenas, Chile – Weddell Sea (East of Ant Peninsula) − * 1987 – Punta Arenas, Chile – Bellingshausen Sea (West of Ant Peninsula) Airborne Gravity, Topo Lidar, Ice Thickness Radar, Magnetics – Twin Otter, BGM ⁻ * 1991-1992 Central West Antarctic 9 NSF Study of Antarctic Margin Average Mis-tie 2.2 mGal Kinematic GPS Era Greenland Aerogeophysics Project 1991, 1992 Greenland Gravity Canada and Eurasia Basin Aerograv/mag Tracks (1992-99) Arctic Aerograv Rampant Lion Project Afghanistan 2006, 2008 Rampant Lion Project Afghanistan 2006, 2008 Rampant Lion Project Afghanistan 2006, 2008 .