KEEP IT MOVING
Varying the height of your boom can have a surprising effect on your rig’s behaviour.
Lowering it can give added control and pin the nose down in tricky, overpowered conditions.
Raising it can create extra lift and assist with early planing.
Some of these effects come from the way they change your stance, but also because of the way they influence your sail’s outhaul setting.
For example, lowering the boom also increases the outhaul tension, while raising it loosens the tension to create more draft.
Changing both boom height and adjusting outhaul (and downhaul) together can give even greater range and settings for your rig to cover a wider tuning band without changing sails. (Add in mast-track positioning and you get even more variety. Forward for control and high wind – back for lighter wind/earlier planing!)
A General Guide:
Down for Higher Wind
Up for Lighter Wind
‘Ideal’ boom height also depends on the type of harness (waist or seat) you use as well as the length of lines you have on the boom – as hook height and the distance you are under and/or away from the boom have a great effect on your stance and how that influences the way you transmit the rig’s power into the board.
Board width also plays a large part in influencing where the boom ‘should’ be set. (The further away ‘outboard’ you are from the rig the lower the boom feels.
WHERE TO START FROM
One general guide to define a starting point for any combo of harness line lengths, boom widths and harness hook heights is to stand, as if sailing off the plane, standing slightly in front of your straps on your board on the beach - across the wind – and hook in and then raise/lower the boom until you feel slightly suspended.
Failing that, try just under shoulder height if you’re standing close to the rig on the board with the sail upright as a starting point to experiment from. Go a little higher for larger sails and wider boards.
An extreme low would be considered just below nipple height and eye level as very high.
Specialist disciplines such as wave or speed sailing also have any number of ‘ideal’ combinations dependent on preference and conditions. (E.g., a lower boom helps with leveraging more radical bottom turns, especially in light wind. Riding waves in onshore wind brings other opportunities for boom-height variation.)
Speed sailors also vary on whether they like low booms and short lines to hold-down power to higher booms and longer lines for lift - and any combination of those to suit the day and find their most effective or efficient stance.
Again, these are all a matter of personal preference.
The best advice is to make small increments of adjustment and feel the results one step at a time.
The best thing about changing boom height for a fast, easy tuning method, is that you can do it on or in the water and do not need to return to the beach.
A change of height can be highly effective if you are suddenly over or under powered and are far from land and unable to adjust your mast track or out/downhaul lines.
Try it next time you’re out sailing and see! Small steps at first and then add in other changes such as mast track and down/outhaul for even better results!