TEL NOF AIR FORCE BASE, Israel – Israel’s air force on Sunday introduced a fleet of huge pilotless planes that can remain in the air for a full day and could fly as far as the Persian Gulf, putting rival Iran within its range.

The Heron TP drones have a wingspan of 86 feet, making them the size of Boeing 737 passenger jets and the largest unmanned aircraft in Israel’s military. The planes can fly at least 20 consecutive hours and are primarily used for surveillance and carrying diverse payloads.

At the fleet’s inauguration ceremony at a sprawling air base in central Israel, the drone dwarfed an F-15 fighter jet parked beside it. The unmanned plane resembles its predecessor, the Heron, but can fly higher, reaching an altitude of more than 40,000 feet, and remain in the air longer.

”With the inauguration of the Heron TP, we are realizing the air force’s dream,” said Brig. Gen. Amikam Norkin, commander of the base that will operate the drones. ”The Heron TP is a technological and operational breakthrough.”

The commander of Israel’s air force, Maj. Gen. Ido Nehushtan, said the aircraft ”has the potential to be able to conduct new missions down the line as they become relevant.”

Israel’s military refused to say how large the new fleet is or whether the planes were designed for use against Iran, but stressed it was versatile and could adapt to new missions. The plane’s maker, state-owned Israel Aerospace Industries, has said it is capable of reaching the Persian Gulf, which would put Iran within its range.

Israeli defense officials said the Heron TP could be a useful tool against Iran. It could provide surveillance, jam enemy communications and connect ground control and manned air force planes.

The officials requested anonymity because they were discussing sensitive military technology.

Israel considers Iran a strategic threat because of its nuclear program, long-range missiles and repeated references by its leaders to the Jewish state’s destruction.

Israel has hinted at the possibility of a military strike against Iran if world pressure does not halt Tehran’s nuclear program. Israel and the U.S. believe Iran is trying to build nuclear weapons; Iran says its program is for peaceful purposes.

Unmanned planes have been used in long-range surveillance and attacking enemy targets with guided missiles in conflicts like Iraq and Afghanistan, where anti-aircraft systems are rudimentary.

They have proven much less successful in conflicts where the opponents possessed better anti-aircraft weapons.

During NATO’s aerial onslaught against Serbia in 1999, for example, Serbian quickly forces shot down 42 U.S. drones, drastically reducing the effectiveness of the campaign.

”We are aware of the dangers such an aircraft can meet in the battlefield, and we do whatever we can to protect it,” said air force Lt. Col. Eyal.

Eyal, whose last name was not disclosed in line with military guidelines, would not comment on how the plane could protect itself from anti-aircraft systems.

Israeli defense analyst Shlomo Brom, a retired general and security expert at Tel Aviv University’s Institute for National Security Studies, called the new drone a breakthrough.

”Its staying power and the height it can reach means it is able to cover ground continuously and it is able to cover large territory,” he said.