Two French pilots hoping to cross the Atlantic Ocean in a specially equipped helicopter were forced by a fuel leak to abandon the attempt Saturday and land on a tugboat.

Gerard David and Phillippe Boutry were following the path of aviation pioneer Charles Lindbergh, who became the first person to complete a solo trans-Atlantic plane flight during his New York-to-Paris trip 70 years ago.

Shortly after their first refueling at sea, the two French pilots noticed a leak in the auxiliary tanks that had been installed in place of backseats. A weld connecting the tanks to the helicopter engine had come loose, causing the loss of fuel, organizers said.

“The problem was with the connection,” Paris-based flight organizer Madie Pescarolo told The Associated Press.

“It was not able to be repaired aboard the ship.”

The helicopter landed on the Abeille tugboat early Saturday, organizers said. It was being transported to a port in the city of Gander, on the eastern coast of Newfoundland.

David and Boutry had expected to finish the 3,700-mile journey in about 27 hours.

In 1967, two Air Force helicopters completed a nonstop trans-Atlantic flight on the eve of the annual Paris air show, refueling in midair along the way, according to Bill Tuttle, spokesman for Sikorsky Aircraft Corp., a Stratford, Conn.-based firm which designs and builds helicopters.

The Frenchmen’s trip was designed to demonstrate the reliability of a new in-flight refueling system, which organizers said had performed well despite the leak.

The helicopter, built by Eurocopter, a Franco-German company, was expected to refuel six times during the flight - two times over land, and the other four over fuel-bearing ships already in the ocean.

The strategy called for Boutry to take the helicopter’s controls while David maneuvered a hose to transfer the fuel.

About 265 gallons were to be pumped into the extra tank in six minutes, and that fuel would then be routed into the main tank, technical director Bernard Certain said.