SBIR-STTR Award

The need for atmospheric pressure, temperature and wind (PTU+wind) vertical profile data over the data sparse open ocean remains a significant problem. Ship-based upper air stations provide synoptic observations but also act as homing beacons for the fleet. Few air-deployed dropsondes are deployedusually only in hurricanes by specially-equipped WP3 and C-130 aircraft. Future advances in the accuracy and capability of Numerical Weather Prediction (NWP) models, particularly in littoral regions near large population centers, hinge heavily upon accurate initial condition data. This data can ideally be provided by in-situ dropsonde observations. What is needed is a low cost and reliable mechanism to enable more routine at-sea soundings. We propose to develop a highly rugged dropsonde technology that is mechanically-compatible with the thousands of ALE-47 electronic countermeasure dispensers widely deployed across multiple DoD manned and unmanned aerial vehicles. The miniature dropsondes will be preloaded into one or more ALE chambers and automatically activate upon release. While in flight, the dropsonde will telemeter PTU, GPS winds, and sea surface temperature to low earth-orbiting data satellites. Near real time data will feed sounding data to the Fleet Numerical Prediction center's NPW models. We call this concept the Automated Dropsonde Atmospheric Measurement System 0x9D (ADAMS).

Benefit:
The technology should reduce the cost of routine soundings and potentially increase the spatial and temporal sampling frequency, improving NWP model accuracy. Dropsondes compatible with existing electronic countermeasure dispensers would significantly leverage the government's substantial investment of thousands of ALE-47/39 dispensers in operation across the fleet. Assuming they are deployed at stand off distances, dropsondes would eliminate the need for expensive ship-based soundings, and in turn eliminate narrow band RF signals near the release ship. Using dispensers will avoid certification costs vs. a new dispenser.

Keywords:
ELINT, ELINT, Weather, sea surface temperature, Meteorology, ALE-47/39, radar chaff, dropsonde, PTU+wind sounding

We will develop a fast response, commercially-available bulk polymer sensor to our field-proven eXpendable Digital Dropsondes (XDD). This task is not only sensor development, but requires developing a precision, automated system to perform multi-point absolute calibration of each polymer sensor plus a means to store these values onboard. This capability will enable real time vertical profiles of RH in engineering units to support direct ingest into meteorological numerical weather prediction models. Reliable, repeatable precision individual sensor calibration represents a major technical task. The second option task involves developing new telemetry receiver hardware and software algorithms supporting very long range UHF data communications. Improved telemetry reliability is essential to eliminate data drop outs that cause discontinuities in observations. Data availability, especially down near the ocean surface in heavy precipitation as is frequently encountered within the inner core of TC/hurricanes, is a key goal. The result will produce a flight-demonstrated practical real time water vapor observation system capable of measuring moisture from the ocean surface to the top of the storm up to 18km, or flight level 650.

Benefit:
Although many scientific meteorological programs would benefit from this technology, our near term primary justification is to support TCI. In the fall of 2015 ONR funded the deployment of 840 XDD devices, using the High Definition Sounding System (HDSS). The HDSS was flown on the NASA WB-57 high altitude research aircraft into four TC/hurricanes (Erika, Marti, Joaquin, and Patricia.) Hurricane Patricia actually evolved into the strongest hurricane on record within the western hemisphere, and ONR was there to observe it. While the HDSS performed reliably, the RH sensor used in the XDD exposed a number of issues, including inability to resolve below -20C frost point temperatures, very slow speed time response and frequent catastrophic failures, most likely due to direct contact with liquid rain hydrosols. While XDDs successfully retrieved high resolution wind speed and direction, temperature, pressure and sea surface temperatures (SST), the lack of RH is problematic to a number of important meteorological research focus areas. Our goal is to fix this core measurement problem and provide accurate moisture initialization of operational and research numerical weather prediction models, specifically to improve the accuracy of TC/hurricane intensity.

Keywords:
Radar Ducting, dew/frost point humidity, upper air sounding, Moisture, polymer sensor, TC/hurricane outflow, Meteorological, RF propagation