Measurement at the Air-Sea Interface with the Controlled Towed Vehicle

The Controlled Towed Vehicle (CTV) provides a unique opportunity to make extended airborne measurements over the ocean surface for extended periods of time. Deployed from a tow aircraft, the CTV can operate at altitudes as low as 10 m over the ocean surface with the tow aircraft maintaining a safe altitude of 1000 to 1200 ft. The CTV altitude setting is controlled via a radio link from the tow aircraft, and the CTV maintains flight altitude with an onboard autopilot and laser altimeter. The measurement payload presently consists of 5 port radome for 3 dimensional wind measurements, fast humidity and temperature measurements as well as carbon dioxide and IR sea surface temperature. Data is recorded on the CTV as well as sent up to the tow aircraft through another radio link. Expansion of the CTV capability to make measurements on sea spray droplets is being planned. Currently the only research aircraft setup for towing the CTV is the U.S. Navy CIRPAS Twin Otter. Feasibility studies are underway to operate the CTV from other research aircraft.