A “Chinese Gybe” (jibe) also known as a “death roll” is feared by many and we need to know how best to avoid them.
You’re sailing dead downwind in windy conditions, and suddenly the boat starts rolling back and forth with increasing amplitude to the point where the boat actually broaches to windward. As the boat is broaching to windward it is also turning sharply to leeward causing it to gybe uncontrolled – “crash gybe”.
See this excellent video clip which captures the action well:
This is quite common on dinghies and also on larger keel boats, especially when using spinnaker. Personally I’ve experienced it numerous times sailing dinghies but only a few times so far in a big boat (40 feet).
Can it also happen with Asymmetrical Spinnakers? Yep, as this lovely clip illustrates and also shows some great crew work recovering from the incident.
What’s the cause?
In order for the death roll to start you normally have a combination of all or most of the below:
- Sailing dead downwind or very close to it.
- Mainsail hasn’t got enough vang on, causing it to twist a lot, hence creating a sideway force.
- Spinnaker too loosely sheeted and not “strapped down”, allowing it to sway from one side to the other
- Boat (slightly) over-powered for the wind it’s sailing in
- Often gusty conditions
- Waves can also help trigger the death roll movements
What to bear in mind
So, what are the steps to take to avoid the rolling to begin?
- Bring on the Vang (also known as “Kicker” in Europe) of the Main very tight, not allowing the twist in the leech. The twist actually causes a resulting force at the top of the sail pointing sideways rather than forward.
Note: This is different from when trying to avoid a broach when sailing on a reach, then you actually release the vang to ease power/pressure from the main.
- If there is a temporary wind gust, temporary set of waves or sail trim hasn’t been adjusted yet the quickest option is to steer up a bit avoiding the dead downwind course.
- The general advice is otherwise to steer to keep the boat under the top of the mast.
- Make sure the crew keeps the weight low, ie no unnecessary standing in the boat. Lowering the centre of gravity makes a huge difference.
- For the Spinnaker we need to bring on the Tweekers maximum, i.e. all the way down to the deck of the boat.
- The spinnaker sheet will also need to be sheeted harder than otherwise (when sailing dead downwind you no longer want the kite to be on the brink of falling in, the normal practice when reaching). You don’t want the spinnaker flying far from the bow of the boat allowing it to shift from one side to the other.
- The Spinnaker pole also needs to be strapped down using the kicker (downhaul) lines to further help control the movement of the kite.
- Let the Spinnaker pole forward a few feet more than you would have in calmer downwind conditions.
If the above actions didn’t seem to help and the tendency to start rolling is still there, well then maybe it’s time to go for a reef or a smaller Spinnaker or go to white sails only. Death rolls are never going to be fast in a racing situation.
If the death roll still happens what to do?
Firstly hang on to the boat for dear life, keeping your head low and avoiding the crashing boom. It is also very important to stay clear of the main sheet and main traveller!
Once the boat has gybed and is down on it’s side the crew needs to take action to get it upright again, and the priority is now to get the power out of the Spinnaker to allow the boat to be raised and also to minimise (further) damage to material or crew. I would suggest “smoking” the halyard, while keeping sheet and brace still on as the safest option which also enables the crew to get the sail in. I’m happy to be told better methods, comments are always welcome 🙂
Here’s some further video advice in the matter: