Have you every wondered why Alex Thomson's Hugo Boss is often under water, or why he has that upside-down bow, or whether he'd be faster with a traditional bow and less water on deck?

In today’s video we are going to answer all of these questions.

You might be more familiar with a traditional raked bow, which is the most common design found on sailing yachts. They provide lots of space inside the boat, for V-berths or anchor storage, they provide for a relatively dry ride because they deflect spray away from the deck and back down towards the water, and they provide a convenient place to mount and launch an anchor, without having to worry about the anchor or rode banging against the hull.

The most notable downside is speed. The ability for a sailing boat to go faster is directly proportional to the waterline length. But with a flared bow you have boat length that isn’t in the water, not contributing to your speed, but you still have to pay for it with your annual moorage, because the marina typically charges for overall length, regardless of what the length is used for.

To maximize waterline length and speed many racing boats use plumb bows. A plumb bow is straight up and down, the way a plumb bob would hang from the front of the boat. For a given boat length, and all other things being equal, a boat with a plumb bow would faster than the same boat with a flared bow. But the builders also need to be a bit more creative in providing places to launch and store the anchor, because it can hit the bow on the way down. Plumb bows also aren’t as good at deflecting spray back down into the water, so you might wind up with more spray in the air, more water on the deck, and a slightly wetter crew, but for racers a bit of wetness is worth the speed.

Most boats will punch their bows through waves going upwind, and it’s not really a big deal because the boat and waves are going in opposite directions, the wave passes fairly quickly, and the water on the deck spills back into the ocean.

But downwind is another matter. A fast boat will climb up the backside of a wave, ride over the top, and accelerate down the face. Depending on the steepness of the wave the bows will submerge a bit when they encounter the back of the next wave. A little bit is not a problem, but if the bow fully submerges, the deck can act like a scoop and slow the boat dramatically. This causes the apparent wind to swing aft at the same time the wave behind catches up with the boat, which can cause the boat to capsize or pitchpole, which you really don't want.

Instead you want a bow that is shaped more like an inverted knife, which can easily slice its way back up to the surface when it submerges.

Disclaimer:
- This content is offered solely for your education and entertainment.
- There are no warranties, expressed or implicit, about any content or its fitness for a particular purpose.
- There are risks of injury, death, drunkenness, and financial hardship involved in sailing.
- The skipper is always responsible for the safety of their vessel and crew.
- Sailing Tips is not responsible or liable in any way for anything that happens on or anywhere near your boat or any boat that we are not in command of.

#sailing #invertedbow #howtosail #learntosail #sailingtips

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