Flying manned aircraft into the carnage of a hurricane has given researchers new means of studying tropical storms, beyond what can be learned from the ground or satellites. But do you know what could be even more fruitful (and safer) than that? Sending in aircraft without anyone on board. This is the objective of researchers at the National Oceanic and Atmospheric Administration (NOAA), who have just completed a successful test flight of their Coyote Unmanned Aircraft System designed to retrieve important data from the eye of the storm to improve hurricane forecasting.

Using unmanned vehicles to inspect hurricanes is something we have seen explored by government agencies before. In 2012, NASA sent a pair of Global Hawk UAVs on a month-long mission to study hurricanes off the east coast of the US. In 2013, an imaginative professor from the University of Florida developed small drones designed to actually be swept up with the hurricane, to gather data on the strength and path of the storm while swirling madly about within.

Developed by defense technology company Raytheon, the Coyote is a small unmanned aircraft launched from the belly of a Lockheed WP-3D Orion (P-3), a manned aircraft fitted with instruments to take atmospheric measurements inside a hurricane and is built to withstand large amounts of damage. But there are still parts of the hurricane that are too treacherous even for the P-3 to go, namely the lower sections of the storm, and that's where the Coyote comes in.

The vehicle was first tested in 2014 during the Atlantic hurricane season, when NOAA researchers carried out a series of missions into Hurricane Edouard at altitudes as low as 400 ft (121 m). Here they managed to gather some useful real-time data on the structure of the storm, but immediately set about improving Coyote's capabilities for future endeavors.

This mostly pertained to boosting the range of the UAV, extending the distance it could fly away from the P-3 while still maintaining a connection with its mothership to relay data. So engineers from Raytheon and NOAA got to work on its upgrades, which included the development and installation of a new antenna and radio.

In its latest round of testing, the team launched the Coyote from the P-3 over Avon Park Air Force Range in Florida to put its new gear through its paces. It provided NOAA researchers with real-time data on atmospheric air pressure, temperature, moisture, wind speed and direction while flying as far as 50 mi (80 km) away, a major increase on the 5 to 7 mi (8 to 11 km) range of the first version. This boosted range was a key objective for the team, as it will enable the P-3 to launch the Coyote and continue on its own flight path at a higher altitude.

Also among Coyote's upgrades is a new infrared sensor for measuring sea surface temperature. As hurricanes feed on warm ocean water, the scientists are hopeful these readings will improve our understanding of how a hurricane draws energy from the ocean, and in turn, how it might grow stronger and or change.

"NOAA is investing in unmanned aircraft and other technologies to increase weather observations designed to improve the accuracy of our hurricane forecasts," says Joe Cione, hurricane researcher at NOAA. "This successful flight gives us additional confidence that we will be able to use this unique platform to collect critical continuous observations at altitudes in the lower part of a hurricane, an area that would otherwise be impossible to reach with manned aircraft."

The team is now looking to boost the battery life of Coyote to make for longer flight times, with a view to making the aircraft an operational component of NOAA's hurricane observing technologies. It says data gathered by Coyote will ultimately be worked into hurricane modeling to fill in data gaps left by the lack of coverage in lower sections of a storm.

Source: NOAA