You're absolutely wrong, period about the V-2. The V-2 was supersonic and there was no warning it was going to hit at all. Only the explosion would be heard.
I did read if one was relatively close to the impact point of a V-2 that a faint whoosh might be heard before impact due to a preceding shock wave but it wasn't loud at all. Being too close to the impact point and one likely wouldn't survive to tell the tail anyways!
The V-1 which was subsonic was correctly identified as the craft one had to be nervous about after the motor cut out. The V-2 there was no audible warning where it would hit. Just a big boom out of nowhere.
My mother's Uncle Clarence was a crew chief (on P-38's) and was in London during both the V-1 and V-2 attacks. He said precisely that. The V-1 one would get nervous when the motor cut out. The V-2 there was no warning and just an explosion out of nowhere.
Uncle Clarence was in the service before the war and was in California early on. Very interesting guy. He related about the early days of the P-38. Standard operating procedure was to bailout with one engine out. He said one day they said Charles Lindbergh was flying to the base in a new (at the time) P-38. When Lindbergh called the tower, word got out to the airbase's men with all eyes to the sky. Lindbergh comes into the pattern with one engine feathered, lands nominally and exited the plane with his r.o.n. bag (remain over nite). Made a comment to the base commander, "It flies pretty well on one engine."
I did read early in the development of the P-38 it was s.o.p. to bailout after losing one engine but I've never been able to confirm the Lindbergh story by other sources.
Sounds plausible though as F.D.R. clipped Lindbergh's wings because of his pre-war pacifist views with the America First movement. Lindbergh volunteered for military service but F.D.R. nixed it as he was pissed at him for his anti-war views.
The day after Pearl Harbor Lindbergh said that it's obvious America First needs to be disbanded (and it was) and he volunteered for service in the military. As said, F.D.R. stood against that and Lindbergh did what he could working for aircraft manufacturers. It's well known he did a lot of flying with the Chance-Vought F4U Corsair and pioneered flying it with very heavy loads and showed the Marines how to use it effectively.
He wrote some about it in his diaries which have been published.
It must be remembered that Lindbergh was pushing 40 when the war started and men were considered "pretty old" when they hit 40 years old. I don't know if there were any 40 year old fighter pilots flying active combat back then as I suspect the military felt it was a "young man's game".
Kurt