By Zachary Fagenson

MIAMI Fla. (Reuters) - A pair of aging airplanes that have flown into more than 100 hurricanes to provide data for U.S. meteorologists are receiving a retrofit this month that will leave just one available to fly when storms threaten the East Coast.

Work on the two so-called hurricane hunters has been staggered over multiple years, ensuring one plane is always available to track a storm's intensity and path, according to the National Oceanic and Atmospheric Administration (NOAA), which operates the Florida-based planes.

The retrofit comes at the peak of hurricane season, after the agency last week predicted fewer storms than normal would affect the Atlantic region for the rest of the year.

Without $35 million in upgrades, the planes would be obsolete by 2019. The enhancements extend their lifespan to 2030 and improve fuel efficiency as the planes fly into winds that can exceed 150 miles (240 km) per hour.

“It’s like riding a giant wooden roller coaster,” said Commander Devin Brakob, a NOAA aircraft specialist who has flown into 15 storms over the past 10 years.

The hurricane hunter aircraft, Lockheed WP-3D Orions built in 1976, have become famous in coastal communities over their decades of risky missions. Each carries radar, weather sensors and computers used to track the storm in real time.

Beginning this month, NOAA will install new computers and electronics systems. Work on their wings would begin next March.

The improvements are part of $310 million in federal aid following Hurricane Sandy provided to the Department of Commerce, which funds NOAA. The hurricane hunters help prepare the eastern and central United States for storms, feeding data to forecasters at NOAA's National Hurricane Center in Miami.

The planes, stationed at MacDill Air Force Base in Tampa on Florida's west coast, typically alternated 12-hour flights through an approaching hurricane. Starting next year one of the hurricane hunters will be available for round-the-clock operations, with two different flight crews, while the upgrades are installed on the other plane, said NOAA spokesman David Hall.

NOAA has never lost a plane during a storm. The closest call was in 1989, when a hurricane hunter flew into the eye wall of Hurricane Hugo and two of its four engines shut down after a problem in the fuel control system.


(Editing by Letitia Stein, Alden Bentley and Eric Walsh)