The Air Force said Sunday that it doesn't appear any regulations were broken when a military crew flying from Alaska to Kuwait stopped off in Scotland and stayed overnight at a resort owned by President Donald Trump.
But it has decided to investigate all such sleepovers anyway, it said, because of a possible perception that it's "not being good stewards of taxpayer funds."
The stop in March at Trump Turnberry, about 40 miles southwest of Glasgow, has been the subject of an ethics investigation by the House Oversight and Government Reform Committee for weeks, but it wasn't publicly disclosed until Politico reported the trip on Friday.
In a letter in June to Patrick Shanahan, who was acting defense secretary at the time, committee leaders said they were investigating whether Trump may have benefited from "receipt of emoluments in violation of the U.S. Constitution."
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In a statement Sunday, the Air Force's chief spokesman, Brig. Gen. Ed Thomas, said the trip was booked routinely through the Defense Travel System using "the closest available and least expensive accommodations to the airfield within the crews' allowable hotel rates."
While Thomas didn't explain why the joint Air Force-Alaska Air National Guard flight was routed through Scotland to get to Kuwait, Thomas stressed that, in general, "the stopover of a U.S. Air Force C-17 in Glasgow, Scotland, is not unusual."
"We have found nothing that falls outside the guidelines associated with selecting stopover airports on travel routes and hotel accommodations for crew rest," he said.
Still, Thomas acknowledged that appearances matter, and he said the Air Force's in-house travel agency, Air Mobility Command, was reviewing "all guidance pertaining to selection of airports and lodging accommodations during international travels."
"We understand that U.S. service members lodging at higher-end accommodations, even if within government rates, might be allowable but not advisable," he said. "Even when USAF aircrews follow all directives and guidance, we must still be considerate of perceptions of not being good stewards of taxpayer funds that might be created through the appearance of aircrew staying at such locations."
Thomas told NBC News that C-17s have increasingly used Glasgow Prestwick Airport as a stopover location since 2015 because it's open around the clock, while other military stopover locations aren't. It also has better weather and is less crowded than comparable Scottish airports, he said.
And Thomas said aircrews regularly stay at commercial properties when "military billeting is unavailable due to capacity limits."
On this mission, the crew — seven active-duty Air Force personnel and Alaska Guard members — stayed at Turnberry on its way to Kuwait and at a Marriott hotel on its way back. The cost for both hotels was below the Air Force's allowable daily rate of $166, he said.