1 / 12

Enhancing Air-Sea Interaction Measurements with a Controlled Towed Vehicle (CTV)

The Controlled Towed Vehicle (CTV) is a revolutionary aircraft-towed platform designed for high-resolution air-sea interaction measurements during extreme weather conditions, including hurricane winds. It allows instruments to operate at altitudes as low as 10 meters, safely below the tow aircraft. The CTV is equipped to measure momentum, heat, water vapor fluxes, aerosols, wave heights, and more, making it invaluable for meteorological studies. Its advanced features include real-time data transmission, altitude control, and effective monitoring, enriching our understanding of boundary layer dynamics and improving operational capabilities in challenging environments.

arista
Télécharger la présentation

Enhancing Air-Sea Interaction Measurements with a Controlled Towed Vehicle (CTV)

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Controlled Towed Vehicle (CTV) A new aircraft-towed platform for air-sea interaction measurements Djamal Khelif & Carl Friehe, University of California, Irvine, CA Bob Bluth & Haf Jonsson, CIRPAS, Naval Postgraduate School, Monterey, CA Jesse Barge, Dan Bierly & Todd Morse, Zivko Aeronautics Inc., Guthrie, OK Larry Mahrt, NWRA Bellevue, Washington ONR SBIR and ONR Marine Meteorology

  2. Purpose: Obtain near-surface measurements over the ocean in high to hurricane winds The Controlled Towed Vehicle (CTV) allows Instruments to ‘fly’ at controlled altitudes as low the canonical reference height of 10 m above the ocean while the tow aircraft is safely above. (In general, manned research aircraft do not fly lower than 30 m or 100 ft). It measures: • Fluxes of momentum, heat, water vapor • Mean meteorology (U, T, Td, Ts, P) & profiles • Aerosols, CO2 • Wave height and direction • Other measurements possible –chemistry, radiative transfer

  3. CTV Instruments • Airspeed vector: 5-hole hemispherical nose cap & pressure transducers • CTP motion and attitude: C-MIGITS III integrated GPS-Inertial unit • Static (barometric) Pressure • Air Temperature: Rosemount Pt Wire • Humidity: LI-COR absorption (2 Hz & CO2); Krypton absorption (50Hz) • Sea Temperature: Heinman IR radiometer NACA Duct

  4. Communication & Control • Wireless link between aircraft and CTV to set height • Smart active altitude control system (Meggitt’s) comprises a radar altimeter, a computer and a wing servo to detect and hold the prescribed altitude. • Video from nose camera is transmitted wirelessly to tow aircraft for display in cockpit and at control station. • Data from research instruments are recorded on CTV data system and transmitted via wireless Ethernet link to aircraft computer for real-time monitoring and redundant storage.

  5. Radar Height Control at 36 feet (11 m) Mean = 36.57 feet (~11 m) ; Standard Deviation = 3.2 feet (~1 m)

  6. Temperature and Dewpoint Profiles

  7. Wind Speed and Direction Profiles

  8. CTV on CIRPAS Twin Otter Control Station 250 W Cont. Power 22.8 cm, (9”) diameter Aft Fore 2.1 m, (83”) Weight: 45 kg, (~100#)

  9. Technology Transfer Towed drones are used for military target training. The MeggittTLX drone is towed from small jet aircraft (Lear, Falcon) and contains a radar altimeter-servo-wing system to skim across the sea surface at controlled heights down to ~10m/30ft. TLX drone (orange) and winch (white, blue) wing-mounted on Lear and Falcon jets.

  10. Conclusions The results obtained from the newly developed CTV indicate that research aircraft will have enhanced capabilities such as: • MABL mean and turbulence measurements as low as 10 m. This was only possible from surface platforms (FLIP, ships, ASIT, spar buoys) BUT these lack the spatial coverage aircraft have. • Simultaneous measurements from two different heights inside the MABL or with aircraft in/above clouds and CTV below/in clouds, respectively (useful to clouds dynamics and processes studies.) • Simultaneous measurements of surface fluxes and wave field mapping/imaging would be possible from aircraft during experiments focusing on wind forcing and wave field coupling such as GOTEX (NSF/NCAR C130) with the bonus of optimized flight time. • CTV may be an alternative to the very likely curtailment of low-level boundary-layer flights with NOAA P3s due to recent operational problems attributed to sea salt contamination of the engines during low flights in hurricanes.

More Related