According to the Smithsonian it was a barrel roll.

Margy

"vincent p. norris" wrote:

As for what they're capable of, remember Tex Johnson(sp?) barrel rolled
the 707 prototype (the "Dash-80").

Actually, an aileron roll, Paul. I know his book, ghost written by
another, says barrel roll, but the tape shows it's an aileron roll.

Among non-fliers, all rolls are "barrel rolls," just as all loops are
"loop-de-loops" and among Southerners, all Northerners are
"Damnyankees."

vince norris