Would people not have referred to what we now call the US Air Force as the Army Air Corp during WWII instead of the term " Air Force"?

It's spelled Corps, not Corp.

The character in the movie was British, and the UK had a "Royal Air FORCE" then, so it would have been a natural mistake.

And during WW2 there was also an administrative branch of the US Army called the "Army Air FORCES," which included the Army Air Corps.

So yeah, the character in the movie was making a mistake, but it wasn't an anachronism, and the scriptwriters could legitimately have intended for her to say that; it could have happened in real life.

I don't remember it as having been called as anything but the Army Air Corps until it was split off from the Army and made the US Air Force. I was only 8 when the war was over, though.

The Army Air Force was created in 1941 as a more autonomous command. the Air Corps stayed around until 1947. There was a lot of overlap during the war. Many in the Air Force were also in the Air Corps. A bit confusing.

The Army Air Force became the US Air Force, a completely separate military branch, in 1947.

The Army Air Force was created in 1941, and the Army Air Corps and Air Force Combat Command as the major components of it. In 1942, the Army was restructured into three components - Army Air Forces, the Army Ground Forces, and the Services of Supply. The Army Air Corps was pretty much done at that point, and working at the speed of bureaucracy, Congress officially disband it in 1947, a couple months before splitting the Air Force off from the Army, and forming it into it's own branch of the military.

So "Air Force" would have been a proper term to use during the war in a less formal way, with "Army Air Force" being more formal.

Actually, it was known as the "Army Air Force" during WWII.

"Air Corps" was replaced in 1942 with the more modern term.