"Depending on what terrain you're in, whether you're in rural or urban terrain, the purpose of angled tiles is so that a blast will go down or upwards, which will allow the impact to deflect outward rather than at the tank crew," Dilling said.
He said the angles of the tiles can be repositioned depending on the situation.
"If you have dismounts on the ground and they're working in close proximity of the tank, you'd want to angle the tiles down so if there was a blast, it would go out and down to minimize the effect against soldiers nearby," he said.
Dilling added, "If you were in an urban environment and you had adversaries shooting from second or third stories or even on rooftops and the tiles were activated, the blast would push out and upwards toward the threat."
https://www.defense.gov/News/Article/Article/1105102/army-unit-bolsters-abrams-tanks-with-reactive-armor
