Depth Under Keel

[Spike88]

I understand that the keel of a ship is the bottom of the ship. And when you ask for a depth under keel its not the depth of the water, but how much water is between you and the ocean floor.
Now my question is, when you ask for a depth under keel report from your navigator, is it always 100% accurate?

The reason I ask this is because I was trying to escape a destroyer, I had already taken moderate damage from depth charges which lead to flooding in the Torpedo room, and also in the two engine rooms. In an attempt to escape I decided to take us low. We were currently at 60 meters and I asked the Navigator for DUK, he reports 24 meters. Not wanting to get too close to the bottom, I order the crew to take us down to 70 meters. We're descending and I can hear the destroyer in the area depth charging close to us. All of a sudden there is a loud sound, and the crew is thrown around. My WO reports that we've taken more damage and that the flooding has worsned. I offcourse cheat and check the external view to see that we have hit the ocean floor. About a minute later we all die due to critical flooding. Is this due to the DUK report being inaccurate or just me making a poor calculation?

[A Very Super Market]

Perhaps a poor calculation, perhaps the sea floor just got higher. The reading is always 100% accurate though.

[Laufen zum Ziel]

If you want a Death Card let me know with a posting of your SHIII Personal file.....
at the D.I.D. thread.Join your shipmates who never returned.......

[Freiwillige]

When you have flooding its harder for your helmsmen to keep the boat trimmed. so ordering a dive of 10 meters probably meant your boat lost controll and was unable to level itself before hitting bottom. How much flooding did you have?:hmmm:

[badwolf]

Hi Spike88,
I usually paddle about in a type IIa and often make attacks in shallow water early in the war. I have often had to skim the bottom at 2-3 metres under the keel in order to get deep as possible to avoid DC's (more maneuvering time). I have found the readings to be very accurate and with my new found skill never hit the bottom.

I can't guess what went wrong in your case.
Here's some of the things I take into account when diving close to the seabed.

1/. Constantly ask for DUK, therefore I have attached the command to one of my 5 mouse buttons for easy access.
2/. When diving you always overshoot your depth until it settles at set depth. The amount of overshoot depends on how big the depth change and speed. Also because of GWX positive bouyancy about 3 metres the sub will rise when settling to depth. So when I calculate the bottom the following is deducted 3 metres for +ve bouyancy + 3 metres for clearence + X metres for overshoot (X depends on depth change & speed). Once the depth is reached, then I make fine adjustments to get to 2 to 3 metres below keel, monitoring that the depth has stablised to that level.
3/. Constantly monitor depth under keel as seabed can rise quite quickly.
4/. Keep at low time compression. Don't increase until depth is stablised (very risky going above 8x).
5/. When making depth changes double check your command before issuing.
6/.Changes of speed alter your depth due to +ve bouyancy, very important when only 2-3 metres under keel.
7/. Watch your crewmen at controls, their actions will help in telling you what the boat is doing.

I had orders to go to East of Fife on a reconnance mission, which is only about 15 metres depth and shore batteries/patrols along the way. Because of the distance I had to travel during the Day 2-3 metres off the bottom. (got back safe though).

badwolf