Poorer performance on starboard tack vs port tack

[Jimski]

I race my Catalina 30 TM. A few races back, I was doing well on a port beat relative to the fleet, making 5.4-5.8 knots. Then tacked at the lay line. On the starboard tack, I was doing well to even hit 5 knots, mostly only able to go 4-4.5 knots (SOG via gps). Two boats passed me on that tack. There was a lot of chop and I attributed the lower performance to nose into the chop and current. The past 2 races I noticed that even in flat water with not current, my speed on starboard is noticeably slower than on port.

I have some very talented crew doing sail trim. We are all at a loss to think of what we should be doing different, or what to check.

Any ideas will be greatly appreciated.

Jim

 

[Alan Gomes]

I race my Catalina 30 TM. A few races back, I was doing well on a port beat relative to the fleet, making 5.4-5.8 knots. Then tacked at the lay line. On the starboard tack, I was doing well to even hit 5 knots, mostly only able to go 4-4.5 knots (SOG via gps). Two boats passed me on that tack. There was a lot of chop and I attributed the lower performance to nose into the chop and current. The past 2 races I noticed that even in flat water with not current, my speed on starboard is noticeably slower than on port.

I have some very talented crew doing sail trim. We are all at a loss to think of what we should be doing different, or what to check.

Any ideas will be greatly appreciated.

Jim

Mast tune, e.g., not centered athwartships? Keel and/or rudder cockeyed/not in alignment?

 

[dlochner]

Are you reading the speed from the GPS or the knot meter? It is not uncommon for the knot meter have different readings in the same conditions on different tacks. It has to do with the impeller placement. As the boat heels the water flow over the impeller is different, thus the readings are different. The best place for the impeller is on the centerline where there is no turbulence. Often a placement there is not possible, so it is placed off to the side.

Assuming the knot meter is correct, then rig tuning would be the main suspect.

 

[Roland5048]

Another thing come to mind. How is the weight in the boat dispersed? On my h30, with the batteries ( 4 golf carts and 1 12v starting batt.) and a 33 gal water tank on the port side, she sails a bit faster and more upright on a port tack. Sorta like having built-in rail meat.

 

[rgranger]

Another thing come to mind. How is the weight in the boat dispersed? On my h30, with the batteries ( 4 golf carts and 1 12v starting batt.) and a 33 gal water tank on the port side, she sails a bit faster and more upright on a port tack. Sorta like having built-in rail meat.

That is where I was going. Does your boat list at all in the slip?

 

[Davidasailor26]

Has the wind been in the same direction each of the races? Could the differences in GPS speed be related to current? Other than that I'd guess as others above about differences in rig tune, trim (fairleads, traveler?) and weight.

 

[Alan Gomes]

That is where I was going. Does your boat list at all in the slip?

Most Catalina 30's tend to have a bit of a port list. What do you notice on yours, Jim?

 

[Jimski]

Speeds measured are GPS - Speed over ground. I dont have a paddlewheel, so dont know speed though water.

I have owned the boat for 5 years. This condition has developed just over the last year or so.

I cant imagine keel/rudder alignment changing over time. I can imagine the rig stretching and changing.

There probably is more weight on port side. Holding tank and galley are on port side. Batteries are stbd. Water tank is stbd but it's empty. I did just empty the holding tank after last week's race. I have not noticed any list in the slip.

This week's races are going to be a drift-a-thon with wind forecast to be 4 gusting to 5.

 

[PaulK]

You report that your gps SOG on one tack is slower than the other. This appears to be regardless of the wind or current direction: starboard tack is slower. Since this has been developing over the past few seasons, weight distribution is not a likely cause - the weight distribution in the boat has probably not changed much. Since everything else (underbody, rudder, hull...) has to be the same on both tacks, it seems possible that something in the rig is making this happen. Are the shrouds the same lengths Port and Starboard? (Replicate the Port shroud setting to starboard, if Port is faster, of course.) Are the jib cars in the same positions P&S? Does the same jib trimmer handle both sheets, or do you have different crew trimming the sheets P&S ? Is the main traveler setting the same on both tacks? Details like these can easily cost a half knot or more, and are also easily overlooked in the heat of competition.

 

[Jimski]

Yes it is the same crew doing the trim. I dont have adjustable cars so we evaluate car location before every tack. If the find is below 12 we can probably get the car moved by standing on the sheet. But yes checking the car position is something we verify before every tack.

I will have to check the shrouds. Its been a couple years since the rig was tuned.. All the standing rigging was replaced 4 years ago.

 

[dlochner]

I will have to check the shrouds. Its been a couple years since the rig was tuned.. All the standing rigging was replaced 4 years ago.

This is most likely the reason. Top racers will tune their rig before each race and in between races during a regatta.

Tuning is more than just getting the shrouds equally tight. the masthead has to be centered between the chainplates and the there needs to be proper rake and prebend in the mast.

 

[Dave Groshong]

It's unusual to not have an adjustable track on that boat, can you show pictures of the lead?

 

[rgranger]

a quick and dirty way to check the rig alignment is to take a halyard from the mast to the toe rail and set the length so that the shackle just touches the toe rail. Then go to the other side of the boat and see if the shackle just touches the toe rail. If not, then you need to tune your rig.

 

[Ken13559]

My h326 has an inherent list to starboard at berth. She seems to do better sailing on starboard tack.

Ken Y

 

[smokey73]

Another thing to check is the lee shrouds in a stiff breeze (say 12 to 15 kts) when close hauled. When you are close hauled on the Port tack check how slack the shrouds are on the lee side. They will be a some tension less than the windward shrouds (possibly even nearly slack). Then tack over to the other side and see if the lee shrouds are about the same tension as the were on the Port tack. Most rig tuning guides say to do this after you have done a static tune dockside.

You mentioned that you had new standing rigging about 4 years ago. After the intitial tuning with the new rigging did you re-tune after a few good sails in a stiff breeze? Even if you're not racing, it is a good idea to check the rig tuning after a few days of brisk sailing when you have installed new rigging. Just my 2 cents and about all that is probably worth.

 

[Roland5048]

That is where I was going. Does your boat list at all in the slip?

Yes, more so when the water tank is filled.

 

[Alan Gomes]

a quick and dirty way to check the rig alignment is to take a halyard from the mast to the toe rail and set the length so that the shackle just touches the toe rail. Then go to the other side of the boat and see if the shackle just touches the toe rail. If not, then you need to tune your rig.

This will give you an approximate read--perhaps close enough. But bear in mind that your main halyard sheave is offset to one side. What would be better is to hoist a sail slug to the top of the mast with a tape measure attached to it. This will be centered in the mast.

 

[Alan Gomes]

Also, while sailing to windward on each tack in maybe 12 knots or so, have you sighted up the mast to see if it is in column?

 

[Jackdaw]

Going upwind, your speed is HIGHLY effected by your angle to the wind. Sailing tighter, your speed will drop off quickly, much more so than the higher angle makes up for.

Now if a boat is trimmed and driven well on both boards, but is faster on one than the other?

An off-center rig will cause this, making you foot slightly on one board, and pinch on the other. This will not be noticeable in the sail, and the trim will look fine. But it for sure be effecting the keel and rudder, slowing the boat. Check that.

 

[rgranger]

But bear in mind that your main halyard sheave is offset to one side. What would be better

True for some boats, not true on mine. I also have a jib halyard sheave that comes directly out of the front of the mast about 3/4 of the way up.