Tactics :- The Lee Bow

Ga'day and welcome  to our first Bottom Up Boats Tactics post. To kick things off I have chosen to to explore one of the most versatile and attacking moves while working to windward. The Lee Bow. This has to be one of my favourite  maneuvers on the race track as it is one of the few times that the trailing boat can attack regardless if you are on port or starboard.

Understanding the physics behind what makes this so effective and the variety of options you have to deploy it will allow you to pass one boat and then the next while beating to windward.

Click on the video below to see some animations on how it works as well as watching GTR execute a perfect Lew bow to protect the starboard lay line.

How it Works.

While beating to windward most sailors know that a wind shadow is created to leeward and behind a boat. This shadow allows the leading boat to pass disturbed air on chasing boats, slowing them down and pushing them backwards.

What many sailors may not know is there is also a small shadow to windward which is created as the air bends around the sails. If you can get close enough to the boat in front and tack to leeward of it, it is possible for the trailing boat to cast a window shadow on the leading boat.  This enables the trailing boat to do the following to the leader.

• Slow the leader down enough for the trailing boat to get clear ahead.
• Force the leader to tack away, these extra maneuvers can be costly as most of the time they will be down speed tacks (a tack done when not at top speed). Down speed tacks are really costly as more ground is lost as the boat takes longer to accelerate up to top speed on the new tack.

When to use it !

While on Starboard Tack

• To protect the right hand side of the beat.
• To gain control of the Starboard lay line on approach to the top mark.

While on Port Tack

• To protect the Left hand side of the beat.
• To slow the leader and force and over take at the next cross.

How to Master It !

Due to the small pocket of disturbed air to windward it is critically important leave your tack as late as possible, this is the best way to ensure you cast your shadow over the leader and effect the pass. This creates risk as you need to complete your tack in such a way to ensure the windward boat (after you have completed your tack) does not have to alter course prior to you completing your tack to avoid a collision. Here are some pointers to help your approach and tack which will put you in the position to take control.

• Once you have committed to the Lee Bow make sure all your crew is giving ample warning on what you intend to do. This will allow them to prepare for the tack and not get mix messages on the course you plan to take.
• When approaching the cross adjust your height and speed (through sail trim) to aim directly at the bow of the the approaching boat.
• Start your tack early and plan to complete a slow tack. This has two advantages, it shows the other boat your intention preventing it from tacking or ducking before you cast your wind shadow on them. Completing a slow tack also allows you to adjust your position throughout the maneuver the without loosing more speed than necessary.
• Once your tack is completed adjust your hight to close the gap to windward on the leader, if the leader starts to sail over the top of you bear away to step forward before coming up again to cast your lee bow wind shadow on them.

Following these steps should allow you to complete your tack within a boat length to leeward of the leader, it will not be long before you are sailing out from underneath them and extending your lead as you push them further into your shadow.