Sailing Wing-on-Wing

I enjoy sailing wing-on-wing occationally. (Yes, I know a direct downwind is the slowest point of sail.) I do it because I think it must look "cool" to the spectators. It's also a bit of a challenge to keep the sails stable on an otherwise ho-hum downwind leg.

But, I've never seen other H-16s try this. Am I just a rebel??? Anyone got pictures of an H-16 sailing wing-on-wing? (I don't know what I REALLY look like, when I'm doing this.)

You're not a rebel; you're just going slower than everybody else.

Every sailboat has a velocity polar graph. Here's one for a J-30 monohull:


Wind direction is straight down; sailing angle to the true wind is the radial axis. Boat speed for various wind strengths is then plotted on the x-y axis. Each wind strength has its own line (there's one for 8 10, 12, 16 and 20 kts on the graph above). Only half the graph is drawn, since it is symmetrical about the y axis.

To determine the maximum Velocity Made Good (VMG) downwind, you draw a horizontal line across the bottom of the graph at the lowest point of the curve, then you can easily determine the gybing angle for maximum downwind VMG.

On the J-30, it varies between 150 and 170 degrees to the true wind direction (you can see the little boats on the graph where the max VMG downwind is).

On a Hobie 16, the curves are more kidney-shaped, consequently, they sail a higher angle to the true wind to achieve max VMG downwind.

Experience has taught us the the optimum angle is approximtely 90 degrees to the apparent wind (not true). I use 12 in. lengths of 8-track tape (cheap, plentiful and perfect width) tied to the bridle to help sail downwind. When one tape points at the other bridle, you're at 90 degrees apparent.

Clear as mud?

have 8 Tracks????

Why am I not surprised!!!

See you in Canadagua!!!

-=0=-

Mbounds, do you know if there are polar plots for the H16 available?

TK - I've got a bunch from when I was in high school (my Mom's '72 Delta 88 had an in-dash 8 track player).

I believe the current selection on the bridle is Stxy "Grand Illusion"

I've also recovered a few left behind in the apartments I manage. My managers know that I'm on the lookout for them, so they save them when they trash out vacants. I have enough to last me the rest of my sailing life.

yes we do, occasionally. one situation is when we are trying to sail down a shoreline in order to stay out of an opposing current. another is when we are trying to stay on starboard to have rights coming down on a leeward mark. also with current considerations. most of the time we like to sail fast on a hot broad reach to go down : )

Most polar plots are the results of a Velocity Prediction Program (VPP), a mathematical model used to predict boat performance. The first VPP's were relatively crude, but as computing power has increased (and you no longer need to pay for processor time on a mainframe), they've become quite sophisticated - and accurate - for larger monohulls.

I have yet to see a "real" polar graph for a Hobie 16. Small boats are tricky (= nearly impossible) to model mathematically for a lot of reasons - mostly related to how light they are (rapid accellerations and turning speeds) and that the crew weight is movable and a high percentage of the total weight (how do you model weight position?). Wave action plays a much larger role, too. A Hobie 16 can sail much lower and faster off the wind when there are waves to surf.

It's only through time and experience that we've been able to emperically derive a rough polar curve of an "optimally" sailed Hobie 16 - and it's very kidney shaped in most conditions.

BTW, Jack Sammons gave this very explanation of "why 16's tack downwind" in his "Welcome to "A" Fleet" books.