Kamikaze tactics

Of all the different types of Kamikaze attacks, those involving airplanes against ships seemed the most effective.

Yet I heard that even with 1000 kamikaze planes, only about 30 ships were sunk and a few hundred damaged- but none of the ships sunk were large carriers. This doesn’t seem very efficient- only one in 30 suicide attacks would actually sink a ship. I had heard that Kamikaze pilots often went after individual ships- so each plane would try to find its own ship to smack into. Of course, this probably made them rather easy to shoot down, since only one plane was coming after any given ship.

What if the Kamikazes attacked in concentrated waves against carriers? It seemed like aircraft carriers were their main target, and created such a concern for the US navy that there would often be a Destroyer screen to try to shoot down the Kamikazes as they approached. The Kamikazes would then attack the destroyer picket (I’m sure a Destroyer is much easier to sink with one plane)

The Japanese navy also tried a few other kinds of Kamikaze weapons- Okha jet aircraft (launched from bombers) and Kaiten manned torpedoes. Neither of these were very effective. The Kaiten actually sounds like a workable tactic, though, because the guy inside could steer the torpedo to its target; I would think it would be more accurate than a conventional torpedo (Which just traveled in a straight line). How come the Kaiten weren’t effective?

The Okha didn’t get much success because the bombers would always get shot down before they would reach their target. But I wonder how effective they would be if they actually managed to launch.

From a site on kaitens:

The kaiten was a cantankerous weapon at best; fast, difficult to control, and prone to uncontrollable dives, broaching, and other accidents. Furthermore, it suffered from a number of mechanical problems, including salt water leakage into the control space when the mother sub was submerged, and a tendency to catch fire from oil leaks. Owing to these difficulties, its value as a weapon was probably inferior to a normal Type-93 torpedo. However, the kaiten did have the added virtue of being able to make multiple runs at a target; the pilot who missed once could reacquire his target and attack again. On the whole, though, they were a miserable failure, and their war record certainly did not justify the expenditure of over a hundred kaiten pilot’s lives during the last months of the war.

Kamikazes were hellishly effective, but since for the most part they were inexperienced pilots flying less than top of the line planes, they were torn to pieces by American fighters. Co-ordinated attacks are hard enough to put together with trained, experienced personnel.

The worst hit of American craft were the picket destroyers, who lost their main advantage of speed because they had to remain on-station.

I’d also guess that the mass and density of a ship is a lot greater than a small fighter plane.
To make the planes efficient they have to be very light weight. While a kamikazee plane may have a lot of acceleration (A), it doesn’t have a lot of mass (M) comparable to a ship.
In order to inflict a damaging force (F) you need F=m*a.

Not to say they weren’t effective, but it’d be pretty hard for one small plane to sink a battleship with sheer ramming force unless it hit a sweet spot.

In addition, look at the 9/11 attacks. They took a 747, rammed the side of a skyscraper, and it structuraly stood it’s ground (until the jet fuel melted the steel structure and it collapsed), but the force didn’t do much structural damage.
And a 747 full of passangers is a lot heavier than a kamikazee pilot in a prop plane.

[QUOTE=Hampshire]
I’d also guess that the mass and density of a ship is a lot greater than a small fighter plane.
To make the planes efficient they have to be very light weight. While a kamikazee plane may have a lot of acceleration (A), it doesn’t have a lot of mass (M) comparable to a ship.
In order to inflict a damaging force (F) you need F=m*a.

[QUOTE]

Or TNT. Weren’t the planes loaded up with explosives?

To me, a success rate of 1 in 30 sounds very high, and from a purely practical viewpoint, it would be a very effective tactic. If you compare the cost of a single plane to the cost of the ship it (might) sink, or compare the body count, I’m sure that a ship would cost more than 30 times a plane, and that more than 30 lives would be lost in its sinking. Add in the other ships which were damaged without being sunk and the fact that the pilots didn’t need much skill or training, and it just gets better.

Good point, Chronos. Anyone know if there was any measurable psychological warfare benefit to the Japanese war effort–what impact did Kamikazes have on the morale of the allied sailors?

Correction: Those were 767s which are half the weight (and fuel capacity) of a 747.

Point of clarification:

Aircraft: Boeing 767-200ER, registration: N334AA American Airlines Flight 11 NY Tower 1

Aircraft: Boeing 767-200ER, registration: N612UA United Airlines Flight 175, Tower 2 South Tower

Aircraft: Boeing 757-200, registration: N644AA American Airlines Flight 77, crashed into Pentagon in Arlington, VA

Aircraft: Boeing 757, registration: N591UA United Airlines Flight 93 crashed near Shanksville, PA

A few reasons why kamikazes weren’t as effective as you might think:

  • Navigation: it wouldn’t have been easy for poorly trained pilots to find targets. Especially when flying far from land over sea where there are few features, or in bad weather.

  • Concentration of attacks: again, badly trained pilots would have had difficulty linking-up and mounting a concentrated attack. The less concentrated they were, the easier it was for AA guns and fighters to pick them off.

  • Fighter cover: the US navy had a lot of carriers at the end of the war, and as the kamikaze attacks increased so was the ratio of fighter aircraft on their decks. IIRC, in the big pacific naval battles about 40% of their planes were fighters and the rest were dive bombers and torpedo bombers. Towards the end of the war they carried something like 80% fighters.

  • Radar: late in the war, the navy was very well equipped with radar, allowing controllers to vector in interceptors quite effectively.

  • Misses: even when a suitable target was found, a lot of attacks would have simply missed, or struck ineffectively (clipping a mast or funnel for example). Their targets might have been travelling at up to 35 knots, which is fast enough to be challenging for a rookie pilot.

  • Damage: it’s very difficult to sink a ship with an explosion above the water line. Probably most ships were sunk by secondary explosions, or abandoned when set on fire. The kamikazes would have been attacking from a much shallower angle than a bomb dropped from a plane, and probably travelling at a lower speed. So the explosives would have been detonating less far down into the ship, with less potential to cause flooding. There were cases where destroyers survived multiple kamikaze hits. In any case, actually sinking a ship is far less important than putting it out of action.

  • Protection: the more valuble the target (e.g. aircraft carriers) the more protection the navy gave it. A higher ratio of kamikaze planes would have been lost going after high-value targets.

  • Duds: kamikazes carried bombs, but its likely that a fair number failed to explode. Even in modern warfare, the number of weapon failures is suprisingly high.
    Despite all these problems, kamikazes were a devastating weapon. I’m having trouble finding decent cites, but their success ratio seems to be much higher than conventional dive and torpedo bombing attacks carried out during WW2.

Some info about kamikaze attacks on carriers.

Even so, it’s a hell of a lot bigger than a Zero.

Maybe you don’t consider it “large,” but the carrier USS St. Lo was in fact destroyed by a kamikaze attack during the Battle of the Leyte Gulf, with heavy loss of life. At 500 feet long and displacing over 10000 tons, it wasn’t exactly a canoe.

Aagramm’s comment about the difficulty in destroying a carrier with attacks over the water line is even true of St. Lo, though; what sank the ship was the secondary explosion of the bomb magazine exploding. You will note that many of the carriers destroyed in WWII were scuttled because, while they were engulfed in flames and unusable, they simply refused to sink. At least two or three of the Japanese carriers lost at Midway were scuttled, and USS Yorktown was abandoned because of above-decks damage but was only sunk when a Japanese submarine found and torpedoed her.