Pirate attacks vary quite alot. I've read countless reports, many of them attempting to engage crew in conversation, or pretending to be in distress. It depends on the quality of the Radars as to whether they will be seen, and the quality of the officer on watch. We usually had difficulity with small fishing boats on radar, but the ones who didnt want to end up at the bottom of the ocean kindly provided lights at nighttime so they were visible. I've only been chased by pirates once, and they gave up after about 20 minutes, think 25 knots and a 13 metre freeboard might have sent them off for a nice easy bulker. Witnessed one attack, 2 high speed fishing boats went alongside a ship underway. Fortunately for them a US destroyer was in the area and responded on the VHF. Pirates must have had a radio aswell, they didnt stick around for long. Both these incidents were in the Gulf of Aden and Arabian sea.
Pirates are well organised, and have much the same equipment as a ship has in terms of communications and navigation. A vessel may only have an officer on watch and maybe a lookout in the middle of the night, when everybody else is asleep. It is very easy to miss a tiny fast moving target on radar.
As for the issue of being armed, I couldn't have imagined our puny water hoses doing much except give them a nice refreshing shower. Weapons, primarily guns, would most likely increase the risk to the crew. Perhaps the crew could successfully repel an attack, but what if they don't? The pirates would, i reckon, be much more willing to kill the crew if they had tried to kill them.
My two pence anyway.
