Comments by "" (@neutronalchemist3241) on "German WW2 Explosive Speed Boats" video.

And better design, and better employment doctrine. To pretend to use explosive motorboats in a mass assault was just stupid. The boats were very vulnerable, so they had to approach the target undetected until it was too late for the ship's weapon to react. Few motorboats could do it, a flottilla was too easily detected.
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In the original Italian boats, the fuse was delayed so that, after the hit, the motorboat sunk below the ship due to the inertia and the shape of the hull, and exploded under it, where the explosion would have made the most damages.
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Even after the war. Their last successes were scored by the Israelis, that managed to buy some war surplus and used them against Egyptian ships in 1948.
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in the Souda Bay raid on 25 mar. 1941, six motorboats were employed, the extremely valuable modern heavy cruiser York (the Brits had few of them) and the 8000t tanker Pericles sunk. In the Malta attack, on 25 lug. 1941, eight motorboats were lost for no losses for the Brits. On April 16, 1945, off the coast of Liguria, a single motorboat damaged the French destroyer Trombe beyond repair. The lesson learned was that the explosive motorboats could be very effective, but only in a limited range of occasions. To attack an heavily defended port was suicidal. The target had to be standing still, or very slowly moving, in a not well protected area. Ships that were assisting a landing or an evacuation, were the ideal targets. On 19 oct. 1948, two former Italian explosive motorboats that the Israeli obtained, sunk the Egyptian flagship El Amir Farouq and damaged a BYMS-class minesweeper beyond repair.
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A good part of the failure was probably due to the attempt to use those motorboats in mass attacks. The Italians succeeded at Suda Bay using only six motorboats. The success of those attacks was tied to the motorboats not being seen until the last few moments but, using a fleet of them, is very likely for it to be spotted early, and the boats to be destroyed by the ships' weapons.
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@thecommentaryking As level of cooperation, that of the Axis was not comparable to that of the Allies, however the Germans used tons of Italian-made torpedos. They surely could have acquired the Italian projects had they wanted, but probably they tought they could do better.
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By looking at the lights at night you can determine if the ship is going left, right (you see only one light) towards you or afar from you (you see both lights, but in opposite positions).
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the Kaiten had been a failure, and the only ship surely hit by a A Kō-hyōteki was an old ferry probably worth less than the sub. It seems that the only axis power that successfully used such devices had been Italy.
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