Most of the pics you see of u-boats is when they are in port(coming or going) and the flag is flying. I was wondering if they just left the flag on the whole time sumerged or not, or if they removed it.. Of course with crash dives and all that, if they didn't just leave it on the mast the whole time, they probably wouldn't put it out very often while at sea. As I want mine depicted as at sea I am debating putting the flag on it

Blaster,
As I understand it the "crash dive" is a bit like an urban myth. Apart from a test dive to check the trim of the boat all dives were made as quickly as possible. Why train to do it slowly when you'd need to do it fast in an emergency.
Flags? I'm not sure, but if the boat was in an operational environment, surely it would be running submerged unless the weather was bad or at night to charge the batteries, so who'd see the flag anyway?
Tom

I have recently read the book "Operation Drumbeat" about the U- boat offensive along the American coast in early 1942. The book follws the exploits of Reinhard Hardegens U-123 and the defensive measures (or lack thereof) taken by the United States. From what I gathered from the book, the U-boats ran on the surface much more than submerged. This allowed them to travel faster, keep the batteries charged and more easily spot smoke plumes and silhouettes on the horizon. They would then submerge to manuever into position and make the attack. They would also stay submerged when in dangerous areas such as the Bay of Biscay, and when danger was imminent, such as day light hours along the coast. Also they would need to "crash dive" if Allied aircraft were spotted. The U-boats would also submerge in rough seas for a bit of respite and to go over the inner works of the torpedoes. This activity was dangerous in rough seas, and it had to be done often.

As for the victory pennants and the flag, they were flown after they had reached the relative safety of the port waters where they were met and escorted in by surface craft. No mention was made of their being flown upon departure from port. If they were, I would assume they were taken down a soon as they were leaving the port waters and escorts behind. I saw no photos of U-boats in combat action flying a flag in this nor any other books I have read.

That's kinda how I figured it too. Now I can use the flag on my 350 scale Bismarck. Or swap out the one on my S-boat kit