The ScanEagle’s launch-and-catch system made it a natural fit for ships, which have no room for a runway. The US Navy contracted for it in 2005 and flew it from destroyers, amphibious ships and patrol craft. In April 2009, when Somali pirates held Captain Richard Phillips of the Maersk Alabama in a lifeboat in the Indian Ocean, a ScanEagle launched by the US Navy helped watch the stand-off that ended in his rescue.

In 2011 the destroyer USS Mahan flew ScanEagles over Libya during NATO’s Operation Unified Protector, and Insitu later said the system had been used to great effect, as AIN Online reported. In 2013 the US Coast Guard used a ScanEagle from a cutter in the eastern Pacific during the seizure of a large cocaine cargo from a fast boat, the first time a cutter-based drone had taken part in a drug interdiction. Navies from the Netherlands, Italy, Brazil, Indonesia and others followed; the Brazilian Navy signed for six aircraft with launch and recovery equipment in December 2019 through the US Foreign Military Sales programme.

On 4 December 2012 Iranian television showed what it said was a US ScanEagle captured after it had violated Iranian airspace over the Gulf. The commander of the Revolutionary Guards’ navy claimed the capture; the US Navy said none of its ScanEagles was missing. Iran then said it had captured two more and, later that month, that it was starting production of a copy.

In September 2013 Iran unveiled the Yasir, delivered to its army ground forces. David Cenciotti of The Aviationist reported that it appeared to be a modified copy of the ScanEagle, with a twin-boom tail and an inverted V tail in place of the original’s tailless layout. Several were shown in Tehran, some partly dismantled to fit in a carrying case. Whatever the truth of the capture, the episode showed how widely the small drone had spread, and how easily such a simple aircraft could be imitated.

• SeaScan: Insitu’s original civil drone for fish-spotting and weather data.
• ScanEagle (Blocks A to E): the military production standard, with day or infrared camera turrets; the US designation was later MQ-27.
• NightEagle: a Block E aircraft with an infrared camera for night operations, announced in 2009.
• ScanEagle 2: introduced in October 2014 with a heavy-fuel engine, a larger nose able to carry day and night sensors together and more electrical power, at the cost of shorter endurance.
• ScanEagle 3: a larger development first shown publicly in 2018.
• ScanEagle X200: a civil version with a restricted type certificate from the US FAA.
• Yasir: Iran’s unlicensed copy, shown in 2013.

In US service the ScanEagle has been flown by the Marine Corps, the Navy, the Air Force and the Coast Guard, and by civil agencies including NOAA. Boeing noted that eight allied nations had adopted it early on. Later users include Australia, Canada, the United Kingdom’s Royal Navy, the Netherlands, Italy, Japan, Singapore, Malaysia, Indonesia, the Philippines, Colombia, Brazil, Kenya, Cameroon, Lebanon, Iraq, Afghanistan, Lithuania, Romania and Pakistan, among others; Defense Industry Daily described it as having achieved wide adoption among US allies.

In August 2022 the United States announced that it would give Ukraine 15 ScanEagles as part of a US$775 million aid package, the first time the type was included, as PBS NewsHour reported. ScanEagles supplied to the Afghan army were reported among the equipment that fell into Taliban hands in 2021.