Tactical question

[scott_c2911]

I bought "Run Silent, Run Deep" and watched it the other day. I was quite shocked at how suicidal the Commander was. He basically played chicken with a jap DD until he was within a 1000yds dived to periscope depth and fired 2 torpedoes at the bow of the DD as soon as the sub levelled off. Would a maneuver like that actually work or would you end up in Silent Hunters version of Davy Jones Locker. I'm inclined to say the later. What do you guys think?

[RussaX37]

I can tell you only that is a movie and that american. watch a german movie
For me das boot rocks

[BigWalleye]

Originally Posted by scott_c2911

I bought "Run Silent, Run Deep" and watched it the other day. I was quite shocked at how suicidal the Commander was. He basically played chicken with a jap DD until he was within a 1000yds dived to periscope depth and fired 2 torpedoes at the bow of the DD as soon as the sub levelled off. Would a maneuver like that actually work or would you end up in Silent Hunters version of Davy Jones Locker. I'm inclined to say the later. What do you guys think?

You might get more satisfactory responses asking this question in the SH4 forum. I don't know if there was ever a U-boat skipper who tried that trick and came back to write a patrol report. I know that Mush Morton did it successsfully in Wahoo (SS-238), but with two important differences to the movie portrayal. First, Wahoo was submerged throughout the engagement, and second, she was cornered in a shallow harbor with no way to avoid the charging DD. Morton was a pretty bold skipper, but even he did not intentionally put his boat in a position where a down-the-throat shot was the only way out.

After Morton and Wahoo returned with the story of their success, some other, even bolder, skipper might have taken it to heart and tried a deliberate down-the-throat setup. I'm not aware of such an incident, but that doesn't mean it wasn't done.

BTW, I do find it amusing to see a carefully crafted piece of anti-war propaganda (Buchheim was an outspoken pacifist.) with its fair share of technical inaccuracies offered as an accurate portrayal of submarine warfare.

[Raptor]

IT IS ONLY A MOVIE - AND A DUMB ONE AT THAT!


FACT: The destroyer's forward battery would have blown the sub to pieces long before they got within 1000 yards of each other. In this movie, the Japanese gunners were the world’s worst shots ever.



As far as the down the throat shot is concerned, my math says it’s not possible, considering the sub starts fully surfaced, then dives to PD and levels off before firing, with only 1000 yards of space.

Given:
A surfaced Gato class sub could do 21 knots
A Fubuki class destroyer could do 35 knots.
A mid-war Gato took 35 seconds to reach periscope depth
The sub begins it’s descent to PD when the two are 1000 yards apart.

Assumptions:
The sub’s speed never changes during the dive (impossible) rather than switching to batteries, which would reduce maximum speed to 9 knots.

The torpedoes were ready for firing in all respects, including opening the outer doors and flooding the tube (highly unlikely while running surfaced at high speed unless a surface firing was planned – which it wasn’t in this scenario).
============
So, we have two objects 1000 yards apart, traveling directly towards each other at a combined speed of 56 knots. The sub starts its dive to PD at this point.

21 knots = 23 mph = 33.7 feet per second
35 secs to PD = 1,181 feet covered by the sub

35 knots = 38.5 mph = 56.5 feet per second
35 secs = 1,976 feet covered by the DD

1181 + 1976 = 3,157 total feet of forward progress
1000 yds = 3000 feet

The DD would have been on top of the sub before it reached PD, let alone had time to fire a torpedo. We won't even discuss the minimum distance the torpedo has to travel before it arms.

Depth charges in the water! GAME OVER ! Nippon wins.

[BigWalleye]

Raptor, a couple of additional considerations:

First, in order to arm itself, the torpedo must travel several hundred yards before impact. Given the closing speed of the DD and torpedo, the torpedo must be launched at least 700 yards from the target (Dick O'Kane's figure. No reason to think he's wrong, although you can work through the numbers if you'd like. "The proof is left as an exercise for the reader.") So, starting at 1000 yards, that only gives the sub 300 yards to reach firing position.

Second, if the sub remains at periscope depth and the vessels stay on converging courses, the DD will certainly impact the sub's conning tower, probably with loss of hull integrity for the sub. (For the DD, too!) So, after firing at range GTE 700 yards, the sub must either go deeper or shear off to one side. And going deeper is not a great option, since the DD will continue forward (and down) even if its bow is blown off. IIRC, Wahoo turned off.

O'Kane's account of Wahoo's shot (he was XO) is pretty gripping. Although they were already at PD, the DD had sighted their scope and they had to keep it extended to observe the DD right to the firing point. (They fired at 800 yards.) Bottom in Wewak harbor was less than 100 feet, so there was no room to maneuver vertically. AND, they had already fired 5 of the 6 bow tubes, so they couldn't launch a spread. VERY high pucker factor!

[Raptor]

Agreed. O'Kane and others made their down the throat shots, but NOT under the conditions described in the movie.

That movie shot was and is impossible. There is not enough distance between the two vessels to allow the sub to get down and fire. It could work if they chose to fire on the surface, but by then the DDs guns would have sunk the sub.

[TG626]

In sh4 I've had successful attacks on DDs by goading them with my scope and pinging them, where upon the charge. We race at one another, while I'm at PD, and I fire on the at about 700 yards. I see them turn, I turn the other way and dive. They turn too late and the fish catches them midships or the stern, usually resulting in a one hit kill. If not they are so badly damaged they run away.

I've done this to clear out 3 DDs leaving an undefended convoy for me to have my way with using my deck gun! :-)

This was stock game and early war. They seem to get a bit smarter in 42-43...

[BigWalleye]

Originally Posted by TG626

In sh4 I've had successful attacks on DDs by goading them with my scope and pinging them, where upon the charge. We race at one another, while I'm at PD, and I fire on the at about 700 yards. I see them turn, I turn the other way and dive. They turn too late and the fish catches them midships or the stern, usually resulting in a one hit kill. If not they are so badly damaged they run away.

I've done this to clear out 3 DDs leaving an undefended convoy for me to have my way with using my deck gun! :-)

This was stock game and early war. They seem to get a bit smarter in 42-43...

Certainly can be done - was done, more or less as you describe. But I wouldn't want to bet money - or my life - on doing it successfully. And, if you said in your patrol report that this was a deliberate tactic, I'll bet Uncle Charlie would be real upset with you.

[maillemaker]

I've got about an 80% success rate taking down escorts in SH3 with down-the-throat magnetic torpedo shots. But it's risky, especially if they approach doing a zig-zag. You have to wait until they level out and start pinging, which they do at about 500 meters. Torpedoes arm at 200 meters. So it is a close thing.

Steve

[Tonnage_Ace]

I either sail in reverse or away from a destroyer, rarely towards him

It's very easy to take out a destroyer this way.

[scott_c2911]

I thought as much. Moral of the story is don't believe what you see in the movies unless it's das boot which is awesome. No offence to any Americans using this site but you like to exaggerate the truth a little don't you especially with war film's

[TG626]

Originally Posted by BigWalleye

Certainly can be done - was done, more or less as you describe. But I wouldn't want to bet money - or my life - on doing it successfully. And, if you said in your patrol report that this was a deliberate tactic, I'll bet Uncle Charlie would be real upset with you.

Just took out another 4 last night this way! Not my fault that when I reported the sighting I got back

ULTRA X CONTACT ESCORTS ARE TO BE CONSIDERED PRIORITY X CLEAR THEM UP FOR FOLLOWUP ATTACKS X

So I sank the 4 DDs and then 7 of the 8 Merchants

Boy do tankers go BOOM when you get a MK14 to blow right under the keel!!

[BigWalleye]

"Realism isn't about the settings. It's about how you play the game." - Rockin' Robbins

[aya]

Hmmm.... from how you described the sequence, seems that it's a very risky manoever. If it were me, I rather be on silent speed or "silent stop", carefully align the torpedoes and fire when conditions are right. If that's impossible, I rather dive deeper and let him pass, if he hasn't seen me - it will be a bad day if he puts me on the defensive, just like this -->

Movies wise, Das Boot is more or less accurate from how they approach and fire torpedoes. The captain there lost sight of the approacing destroyer, which happens to me in rough waters/bad weather. I also remember the moment they attacked the convoy, doing the calculations and all, whilst they forgot that a destroyer is approaching them... ALARM!!!

[BigWalleye]

Originally Posted by aya

Hmmm.... from how you described the sequence, seems that it's a very risky manoever. If it were me, I rather be on silent speed or "silent stop", carefully align the torpedoes and fire when conditions are right. If that's impossible, I rather dive deeper and let him pass, if he hasn't seen me - it will be a bad day if he puts me on the defensive, just like this -->

Movies wise, Das Boot is more or less accurate from how they approach and fire torpedoes. The captain there lost sight of the approacing destroyer, which happens to me in rough waters/bad weather. I also remember the moment they attacked the convoy, doing the calculations and all, whilst they forgot that a destroyer is approaching them... ALARM!!!

Based on their record of achievement and on personal accounts, the KM was far more professional and competent than the portrayal in Das Boot. And the movie was less accurate than the book.