The Jerusalem Post reported Sunday that the UAV, known as the Eitan -- Hebrew for "strong" -- went down near Tel Nof Air Base south of Tel Aviv "after it performed a maneuver beyond its capabilities, causing one of its wings to break off."
The daily said the craft, built by Israel Aerospace Industries, was flying with "a new navigation component that, the air force suspects, might have disrupted the drone's automatic flight systems."
The air force and IAI are investigating the crash.
The Post reported that the air force commander, Maj. Gen. Ido Nehushtan, said at a conference on air and space strategic studies in Tel Aviv that IAI was testing new technology on the Eitan when it crashed.
There were no other details on that equipment but it came amid growing concerns that Israel was moving closer to launching pre-emptive air and missile strikes against Iran's nuclear infrastructure.
The Eitan reputedly can fly as far as Iran and there has been much speculation that it would be used as part of any assault on the Islamic Republic, either for reconnaissance and surveillance, or armed with air-to-ground missiles.
Nehushtan told the conference that Israel's long-held air superiority in the Middle East was being eroded since the country's adversaries are being equipped with increasingly advanced weaponry, some of which could end up in the hands of terrorists.
The Eitan went into service with the Israeli air force in 2010 and the first squadron equipped with the giant drone had been expected to become operational sometime in the next few weeks after working up an operational doctrine. That could be delayed because of Sunday's crash.
But as far as is known, the 4.5-ton plane, with a range of around 700 miles and a flight endurance of up to 45 hours, both depending on payload, wouldn't be able to fly to Iran and back. The Eitan in its current configuration is primarily designed to conduct long-endurance, high-altitude electronic surveillance missions well above commercial air traffic.
"With 24- to 36-hour endurance and the ability to operate above 40,000 feet, the Eitan certainly provides a noteworthy new capability for Israel," the U.S. global security consultancy Stratfor observed when Eitan was unveiled.
"But the UAV is something IAI has long been capable of designing and producing and it does not materially alter Israel's ability to strike Iran."
Stratfor noted that although the Eitan could reach Iran it would have to fly through Iraqi airspace -- then controlled by U.S. forces -- to get to Iran and that was too "politically sensitive" at that time.
But U.S. forces completed a withdrawal from Iraq in December, making the option of using Iraqi air space less of a problem.
Stratfor noted that the Eitan "does not have the capability to fly around the Arabian Peninsula, reach Iran and return to Israel."
The Eitan is the biggest UAV in the Israeli arsenal. It is 79 feet long with a wingspan of 86 feet. It has a powerful 1,200-hp turbo-prop engine and can carry a 1-ton payload at altitudes of up to 40,000 feet.
In terms of endurance, the Eitan has roughly the same capability as the U.S. MQ-9 Reaper, the latest variant of the Predator UAV, which has been used to eliminate leaders of al-Qaida and the Taliban with salvos of AGM-114 Hellfire ground-to-air missiles.
Israel doesn't divulge the offensive capabilities of its UAVs but Stratfor noted, "While there is little doubt the Eitan can be fitted with Hellfire missiles and perhaps even configured to carry 500-pound bombs, Israel's challenge is delivering 5,000-pound bunker-busters to Iran in order to damage key nuclear facilities."
IAI is one of several companies involved in the development of UAVs and these have become a key defense export item. In July 2011, IAI secured a $500 million contract from France for the Eitan, the first export deal for the craft.
"The deal is expected to lead to additional contracts for IAI as other countries, such as Germany, upgrade their UAV capabilities," the Post reported.