Manual Targeting Failure

[Pisces]

Well, the 3 minute 15 second plot is good for getting a quick fix on his speed. But it isn't that accurate. It's better to take an average over a few intervals. 4 intervals are 13 minutes. Which is just long enough what the stopwatch can show. 12 minutes on the small handle, and another lap of the big one. And you get the speed known to a quarter of a knot. Much better the TDC won't take anyway.

But if the target really was at 500 meters in front of you then it should have hit anyway. 1 knot of speed difference alone cannot make that much of a miss at this distance.

The target can speed up if it does see the bubble wake of the type 1 torpedo. So it may have tried to dodge it successfully. Remember the near Tramp Steamer in the torpedo academy mission? How sure were you of your stealth?

Other than that I can only imagine the Torpedo speed setting bug messing up the TDC when switching between tubes with a type 1 and type 2 with different speed settings. In the future you can check this manually if it is correct with a rule of thumb (assuming near 90 AOB):

Lead angle= 60 * Target speed / Torpedo speed

[maillemaker]

It was no more than a minute underwater and I got hydrophone contact and a line showing the merchant on the anticipated course. I raised the observation periscope and tried to find the ship, but I noticed the gyroangle wasn't updating.

Yup, forgetting to turn the TDC on and off can ruin an attack, for sure.

3:15 will give you the exact speed [i]if you are 100% certain of the ship's position at the start and stop of the time.

If you are 100% realism without map updates, then your map solution may not be 100% certain.

I try to shoot at less than 1000 meters, and I still miss, too. It all comes down to knowing their speed accurately.

Steve

[Zosimus]

I'm still not sure why I missed, but I've had better success now that I always set the torpedo depth to 2 meters rather than 5.

[Zosimus]

Yeah I had that happen once, but I figured it out long before I took the shot. The gyroangle was showing zero on the wrong side of the 0º bearing.

[maillemaker]

Yup, that's happened to me before, too.

Also I have tried down-the-throat shots at pursuing destroyers only to realize after firing that I forgot to dial the target speed back down to zero...

Steve

[Zosimus]

I've gone pro! I've recently scored three perfect hits on merchants from as far away as 2300m. It's not nearly as hard as I'd feared. The only problem is they don't go down on the first torpedo. With winds at 13m/s I can't man the deck gun. How long should I wait to be certain the merchant isn't going to sink? An hour? Two?

Tips:

Always measure speed for at least 6:30, not 3:15.
Always determine your gyroangle before firing (11-12º for 6 knot ships).
Measure distance to target down the gyroangle bearing, not the perpendicular bearing.
Don't just call all stop when you are at your desired range: Call back slow until the speed drops to 0 then call all stop.
Always double check your torpedo depth setting.
Always double check that you are on the desired perpendicular heading.

[maillemaker]

I pretty much have resigned myself to two fish per target. It's the only way to be reasonably sure the ship is going to sink in GWX.

It always annoys me when the ship goes up like the Fourth of July on the first hit and then the second fish is already on the way.

Steve

[banryu79]

Originally Posted by Zosimus

Tips:
...
Measure distance to target down the gyroangle bearing, not the perpendicular bearing.

If I position my sub with reaspect to tgt track for a straight 90° attack and I set up the TDC accordingly, with torp speed of 40 kts and target speed of 8 kts, I should read a 000° gyro angle when my periscope bearing is pointing at +/- 12° (firing bearing) from 000° bearing.
So are you saying that the range to input in the TDC is not the length of the perp line that connects my sub to tgt track? But is the length of the line that connects my sub with the tgt itself when it is crossing the "firing bearing"?

If so this is against everything I had red on many, many tutorials out there...

Originally Posted by Zosimus

How long should I wait to be certain the merchant isn't going to sink? An hour? Two?

According to the "Submarine Commander Handbook" under Section IX "Use (Expenditure) of Torpedoes" -- If, in remote sea areas, an early arrival of enemy defence forces is not to be anticipated, the final shot should not be precipitated. Many ships sink only after 2 to 3 hours. --