For Questions That Don't Merit Their Own Thread

[DDE]

1 hour ago, wumpus said:

No idea if the brits could have mounted proper bombs to the Swordfish

The Swordfish was fully certified for dive bomber ops.

2 hours ago, wumpus said:

The armor was in the right place for the aircraft used against it

Utterly false. The main belt ended about 1500 mm below the nominal waterline. Lower than that, as usual, were the longitudinal bulkheads, sacrificial compatments and fuel tanks forming the integrated, non-bulging torpedo “bulge”, butressed by a mere 45 mm of Wotan weich soft steel.

[wumpus]

1 hour ago, DDE said:

The Swordfish was fully certified for dive bomber ops.

Utterly false. The main belt ended about 1500 mm below the nominal waterline. Lower than that, as usual, were the longitudinal bulkheads, sacrificial compatments and fuel tanks forming the integrated, non-bulging torpedo “bulge”, butressed by a mere 45 mm of Wotan weich soft steel.

From: https://forum.axishistory.com/viewtopic.php?t=210236

"When using an impact pistol, 2-3m (6-9 feet) would be a normal/typical depthsetting."  So it should have hit below the belt.

I'm assuming a mark XII torpedo (thanks to this link: http://www.navweaps.com/Weapons/WTBR_WWII.php ).

But I doubt the armor belt mattered at all in taking out the rudder.  And I'm not sure anyone wanted to dive bomb the Bismark with a biplane.  Staying far away and dropping a torpedo sounds much better.

[DDE]

18 minutes ago, wumpus said:

Staying far away and dropping a torpedo sounds much better.

WWII experience brutally disagreed. Most sources indicate the dive bombers had it easier than the torpedo bombers coming in nice, slow and low.

[magnemoe]

4 hours ago, wumpus said:

The rudder was destroyed by a biplane carrying a torpedo.  The armor was in the right place for the aircraft used against it (of course, had it lasted longer it would have been obsolete soon enough), but I'd expect any sort of anti-aircraft to be able to take out a biplane (although riddling cloth with bullets isn't all that effective).

No idea if the brits could have mounted proper bombs to the Swordfish or knew enough about the Bismark's construction (how do you hide the construction of a battleship?) to mount bombs.  Sometimes its better to be lucky.

You would need an huge bomb to take out an battleship. So you needed an heavy bomber, have fun trying to hit an moving target. 
Torpedoes hit below the waterline and the water increased the explosion effect. they also only have one axis to miss in. 

Yes you can use dive bombers to take out the AA guns like the US did against Yamato. Most of the AA guns just had gun shields so this and staffing worked taking them our or suppressing them so the torpedo bombers could do an run.
US used some hundreds planes, second line of defense was 6 battleships. 
No it was not as stupid as it sounds some US carriers at the end of WW2 had a gun deck below the runway like an old ship of the line stacked with 20mm guns, 

And dive bombers worked against carriers as they was mostly lightly armored and even if armored it would damage the runway stopping air operations for some time. 

[tater]

27 minutes ago, wumpus said:

Staying far away and dropping a torpedo sounds much better.

Far away?

WW2 aerial torpedoes were typically pretty ineffective in general, and when they did work (actually hit), they were usually dropped close.

The USN eventually ended up not using them often, often loading TBFs with bombs, instead (not that glide bombing was very effective, vs dive bombing).

The most successful low altitude anti-shipping attacks in the PTO were probably skip-bombing attacks. Spray MG fire on ingress (keep the AAA gunners' heads down), drop bomb, it skips like a stone a couple times, then hits waterline.

[DDE]

2 hours ago, magnemoe said:

You would need an huge bomb to take out an battleship.

Not if you’re accurate enough to send it right down the smokestack or land an 225 kg or 450 kg delay-fused AP bomb hit on the magazine, neither of which was egregious. Lots of one-hit-kill scenarios; plenty others capable of causing grievous damage, or at least a fire, which can easily have devastating consequences. It were rocket-armed fighters that did the AAA suppression.

[wumpus]

5 hours ago, DDE said:

WWII experience brutally disagreed. Most sources indicate the dive bombers had it easier than the torpedo bombers coming in nice, slow and low.

Sure.  But by that point the British had sunk the Graf Spree and little else.  While the Bismark might have registered zero hits after the biplane attack, it still appeared a heavily armored mass of guns.  Launching a torpedo from up to 3km (ok, that's way too far.  But easily 1km (which only needs 7 degree accuracy.  2km needs about 3.5 degrees) [which allows an additional 10% faster torpedo] away that you only need to be accurate in a single dimension (which could be the whole 240m length) sounds a better tactical chance of getting a chance to launch another torpedo.

I suspect that the "had it easier" involved carrier supplied air cover.  In Midway, the Japanese zeros swooped down and massacred the initial wave of torpedo bombers (there was a single US survivor who bounced off a carrier deck and was taken prisoner).  When the next wave of US dive bombers came in high, the zeros were far to low to do anything about it and US pilots pretty much attacked Japanese capital ships at will.  I really don't think that swooping down on a battleship is going to be safer from the AA than firing from a km away (but going low and slow makes you a sitting duck against enemy fighters).

(far more detailed claims are made here, referencing a work I've heard is good [it points out that my story is part myth and part oversimplification] : http://ww2f.com/threads/battle-of-midway-torpedo-bombers-faulty-torpedoes.39656/

Note that the claim (from my link) "it is very difficult to stop a dive bomber after it begins its dive".  First, the USN was not using biplanes at the time and second that doesn't mean it is any easier to get close enough to begin to dive or safe to get away after you completed your bombing run.

[Xd the great]

Dive bombing is more effective. Torpedo bombing is way too slow, even if each torpedo packs more punch.

Oh, and dive bombers csn strafe, but torpedoes cant, which means they can do Anti Anti Aircraft stuff. 

[magnemoe]

11 hours ago, DDE said:

Not if you’re accurate enough to send it right down the smokestack or land an 225 kg or 450 kg delay-fused AP bomb hit on the magazine, neither of which was egregious. Lots of one-hit-kill scenarios; plenty others capable of causing grievous damage, or at least a fire, which can easily have devastating consequences. It were rocket-armed fighters that did the AAA suppression.

I hope the force is strong in you for you need it

 

[DDE]

5 minutes ago, magnemoe said:

I hope the force is strong in you for you need it

 

I don’t need the force, my plane is faster than a drunken snail carrying a bottle of nitroglycerin.

 

[kerbiloid]

2 hours ago, Xd the great said:

Dive bombing is more effective. Torpedo bombing is way too slow, even if each torpedo packs more punch.

The skip bombing.

Spoiler

 

 

[Xd the great]

11 minutes ago, kerbiloid said:

The skip bombing.

  Hide contents

 

 

This is hard, as you have to gauge altitude and speed and whatnot, often missing the target.

Dive bombing is relatively easier, just point your plane at the ship and kaboom.

[kerbiloid]

4 minutes ago, Xd the great said:

This is hard, as you have to gauge altitude and speed and whatnot, often missing the target.

This is a common practice of WWII.

When you are dive bombing you have to target even more accurately, and every miss is a miss.

Edited January 30, 2019 by kerbiloid

[tater]

16 hours ago, wumpus said:

(there was a single US survivor who bounced off a carrier deck and was taken prisoner)

Source?

Ensign George Gay survived the the Torpedo 8 (VT-8) attack of the Kido Butai at Midway. He dropped at ~800 yards, and flew over Soryu's flight deck. He was subsequently wounded and his Devastator cartwheeled, but he none the less survived. He was picked up by a PBY (US) almost a day and a half later. He was not captured.

16 hours ago, wumpus said:

I really don't think that swooping down on a battleship is going to be safer from the AA than firing from a km away (but going low and slow makes you a sitting duck against enemy fighters).

That also assumes appropriate amounts of AAA available. The Kriegsmarine had OK surface combatants (though basically none of them) for WW1, but they were not acceptable for WW2, they had no AAA to speak of. As I said above, Bismarck literally had less AAA capability than a single USN DD from 1944.

The IJN similarly increased AAA capability on all their vessels as the war progressed, but even early war USN/IJN ships were more capable than Bismarck in that regard.

 

[Gargamel]

8 hours ago, Xd the great said:

Dive bombing is relatively easier, just point your plane at the ship and kaboom.

No.... just no..

There's a reason the swordfish was mainly used as a torpedo bomber.    It is much easier to get into a standoff position, coming straight on to your target, and release a torpedo.  To dive bomb, you must first get overhead, then execute an accurate bombing run.  The act of getting into that position exposes you to a lot more AA fire than a torpedo run would.  Plus, a torpedo is lot more efficient at sinking or disabling a ship than a bomb is. 

[ARS]

The fact that Bismarck's rudder jammed probably accounts for the condition of the ship the moment the torpedo hit. It was maneuvering at battle speed, where, aside from rudder being turned, the ship's propeller spins at high RPM. An exploding torpedo on ship's stern could deform the structural parts of the ship which could jam the rudder or destroy the propeller (also happened with HMS Prince of Wales, which is sunk after just a single torpedo hit). There are reports that the personnel on board tried to destroy the rudder connection to prevent Bismarck being steering locked, with the propellers being used for turning (which is very difficult, considering Bismarck has triple propeller layout instead of quad, making it very limited in terms of being used as a substitute rudder)

[p1t1o]

6 hours ago, ARS said:

 could deform the structural parts of the ship which could jam the rudder or destroy the propeller 

The propellers were apparently in perfect condition, but the explosion did cause a "whiplash" effect in the larger structure, transmitting violent forces which can cause quite widespread structural damage.

Edited January 31, 2019 by p1t1o
How did that part end up in a quote?

[DDE]

16 hours ago, Gargamel said:

It is much easier to get into a standoff position

No such thing as a stand-off position with torps from that era, they all required venturing into 20 mm range.

Furthermore, torpedo design imposed a pretty hard cap on the maximum speed at release. And the torpedoes were noticeably heavier than practical dive bombs.

In addition to that, AA effective range takes shape of a flattened dome, so dive bombers would be less exposed on approach, and reach wing-snapping velocities by the time they ventured into the innermost AAA radius, reducing their exposure time. Finally, a poor man’s AAA was shooting impact-fused artillery to send columns of water up in front of torpedo bombers.

All of this translated into dive bombers being more survivable.

16 hours ago, Gargamel said:

Plus, a torpedo is lot more efficient at sinking or disabling a ship than a bomb is. 

It’s not. Bombs tended to strike something on the fairly valuable superstructure, while torpedoes end up hitting the thick lard of specialized sacrificial compartments, leading to a slow demise at worst. By WWII anything bigger than a destroyer was fairly well-hardened against torpedoes and associated flooding, and destroyers died from an angry stare anyway.

[wumpus]

19 hours ago, tater said:

Source?

Ensign George Gay survived the the Torpedo 8 (VT-8) attack of the Kido Butai at Midway. He dropped at ~800 yards, and flew over Soryu's flight deck. He was subsequently wounded and his Devastator cartwheeled, but he none the less survived. He was picked up by a PBY (US) almost a day and a half later. He was not captured.

That also assumes appropriate amounts of AAA available. The Kriegsmarine had OK surface combatants (though basically none of them) for WW1, but they were not acceptable for WW2, they had no AAA to speak of. As I said above, Bismarck literally had less AAA capability than a single USN DD from 1944.

The IJN similarly increased AAA capability on all their vessels as the war progressed, but even early war USN/IJN ships were more capable than Bismarck in that regard.

The "bounced" was from memory of an exhibit at the Smithsonain, which I thought was using quotes from Ensign Gay.  Being picked up by the US seemed vastly improbably considering he must have gone down close to the Japanese fleet, but that would explain his survival.

Had the British used dive bombing attacks, I'd expect the Germans to provide a counter as soon as possible.  I don't see any mention of bombers in the sinking of the Graff Spree (an early British navy victory), and it doesn't appear to be something they thought important (like US admirals, only worse.  See the "rum, sodomy, and the lash" quote from Churchill).

[Guest]

On 1/5/2019 at 4:28 AM, Mad Rocket Scientist said:

On mobile, accidentally quoted and now can't remove it. I'm sorry.

Internal combustion engine-related question.

From what I've heard, two valves per cylinder allow for greater power in the lower RPMs, whereas four valves per cylinder push the power to the high end of the RPMs.

In order to get the best of both worlds, what complications would arise from making a "hybrid" camshaft, as in half of the cylinders having 4 valves, and the other half having two?

I imagine the overhead camshaft would be more complicated, but not by much. Could there be any problems with balancing forces, or something else that would make this undoable?

[tater]

38 minutes ago, wumpus said:

Being picked up by the US seemed vastly improbably considering he must have gone down close to the Japanese fleet, but that would explain his survival.

The Kido Butai had to high tail it out of there after losing 4 of 4 CVs, and the US was obviously going to keep patrolling. Yeah, had he been captured his chances of surviving as a POW would have been pretty lousy.

52 minutes ago, DDE said:

It’s not. Bombs tended to strike something on the fairly valuable superstructure, while torpedoes end up hitting the thick lard of specialized sacrificial compartments, leading to a slow demise at worst. 

Yeah, main guns ideally wanted to be at long range to guarantee "plunging fire" through the decks, vs at shorter range where flater trajectories put rounds into belt armor (and arriving at an angle, increasing effective thickness).

 

52 minutes ago, DDE said:

By WWII anything bigger than a destroyer was fairly well-hardened against torpedoes and associated flooding, and destroyers died from an angry stare anyway. 

 

Not always, look at Taffy 3. USN DDs decided to attack the main IJN fleet (that was blasting US Escort Carriers) near Leyte. They rushed in, and their lack of armor, and tiny size meant that they would get hit by large guns, and the AP rounds literally went in one side, and out the other.

[tater]

17 hours ago, Gargamel said:

No.... just no..

There's a reason the swordfish was mainly used as a torpedo bomber.    It is much easier to get into a standoff position, coming straight on to your target, and release a torpedo.  To dive bomb, you must first get overhead, then execute an accurate bombing run.  The act of getting into that position exposes you to a lot more AA fire than a torpedo run would.  Plus, a torpedo is lot more efficient at sinking or disabling a ship than a bomb is. 

Reiterating what was already said. There was no "stand off position" for aerial torpedoes in actual use, they planned for farther ranges before the war, but experience quickly showed that dropping torpedoes at any distance was a waste of time and men. 1000 yards would have been dropping far away, any farther and the ship would comb them.

Dive bombing would have been a little harder for the Axis vs the USN because of the radar-fused 5/38 DP that was on pretty much every single US ship in the Pacific (they didn't use it in the ETO until late in the war since they ddin't want the Germans to ever figure out we had it).

[kerbiloid]

_{As I wish to add something clever, but can't, so just leaving a link.}

Spoiler

 

 

[DDE]

46 minutes ago, tater said:

Yeah, main guns ideally wanted to be at long range to guarantee "plunging fire" through the decks, vs at shorter range where flater trajectories put rounds into belt armor (and arriving at an angle, increasing effective thickness).

Oh, it’s worse. There’s a not-so-sweet spot where both deck armour and main belt are at a very inconvenient angle.

[tater]

51 minutes ago, kerbiloid said:

_{As I wish to add something clever, but can't, so just leaving a link.}

Nice link. That's of course extremely late war. The Japanese, OTOH, dropped a little higher and substantially faster than early war USN torpedo bombers did (the IJN had by far the best torpedoes of the war (air and ship/submarine launched)).