The Airbus Zephyr S - which is solar-powered - remained in the air for 26 days in a row and beat the record set in 2018 by the manufacturer’s older model of 25 days.
The aircraft - which has no pilot - soars high into the atmosphere to avoid other air traffic and poor weather conditions. In addition, it has batteries, cancelling out the need to stop to get fueled up.
Data collected after the plane landed showed that it went from take off in Arizona before landing in Belize before making the same journey in return.
A United States Army Futures Command spokesperson told The Drive that these tests are “"intended to test the UAV's energy storage capacity, battery longevity, solar panel efficiency, and station-keeping abilities".
The editor-in-chief of Aerospace magazine, Tim Robinson believes that the feat marked “important demonstration”.
He told BBC News: "They've flown over the range from 2018 when it set the previous record.
It's transmitted out to this area and beyond line-of-sight communications, and it's gone somewhere else.
"I think that's an important demonstration of how you would use it in reality."
One of the benefits of the aircraft is that it can act like satellite, collecting images and other data.
Tim said: "It comes back to you. You can upgrade sensors on it, you can switch the payloads out, you can upgrade it with a new technology."
The aircraft - which was designed and manufactured in the UK - was invented by the late Chris Kelleher in 2003, who Airbus named them after following his passing in 2015.