In the Stairwell sings 'Castle on the Hill' on America's Got Talent Semifinals

The U.S. airforce acappella group In the Stairwell performs there rendition "Castle on the Hill" on America's Got Talent Live Semifinals on Tuesday, September 12, 2017.

“Thank you for your service. You really touched me. You deserved to be here, you just sound incredible,” said Mel B.

“This time, I really genuinely felt it. I thought you did great and we might see you in the finals,” said Simon.

“You did what you just did and I love it,” said Howie.

“You did good and you gave your 100 percent,” said Heidi.

Results of the public voting will be announced on Wednesday, September 13. Cast you vote here!