PHRF Hotlaps 2009 !!!!

OK. Which boat is faster, a Trucordia Yawl, an ACC2, a Leetle Cat, or a Tetra 35? And by how much? What are the time handicaps when they race in a mixed fleet? How about a Skutsje, a Fizz, an ACA33v1.6 or ACA33v1.9? Where does the brand new ACA33v2.0 fit? All of these questions can answered by comparing boats using a PHRF Hotlaps system.

PHRF Hotlaps 2008

In 2008 we spent several months collecting Hotlaps data. A couple dozen skippers  jumped in to help, comparing over 30 different types of boat using six different race courses.   Their enthusiasm was  infectious; over that few months the start gun must have gone off several thousand times to yield the final data set of 650 laps scores used to compare boats and generate handicap factors for racing.

Much of the original data was posted on the Forum, and there were many threads and articles discussing the results. The bottom line was pretty clear: Handicap Hotlaps results turned out to be a valid index of boat performance with an extremely high statistical reliability.  Just one example that I’ve talked about before: Liv Leigh last year used the Hotlaps data to question one of the lap time results submitted by Stuart Coche. Stuart immediately agreed that of course something funny could have happened on one particular lap out of so many, and we all decided it would be interesting for him to repeat that lap… but before he did, Liv and I used the tables to predict his finish time. 

Well, Stuart turned out to be better than we thought… (grin). He beat our prediction by one second!

Despite the fact that we used six different courses, shared the raceline with all the regular fleet races and put up with the standard interferences, the PHRF Hotlap results turn out to accurately predict a boat’s lap performance within about 3%. When we originally set up the project, we all thought 10-15% error would be reasonable, given all the potential sources of variance. Three percent was truly remarkable! There was similar consistency among the sailors themselves, and looking across the entire fleet, the evidence appeared to show that slower sailors were actually only slightly behind the fastest ones. That should be huge encouragement to a new skipper, someone who’s been around for a month or two but never seems to finish at the front of the fleet. The pattern of PHRF scores appears to show that there’s no secret  trick to winning sailboat races. That skipper who keeps eating your lunch every day is beating you with only a 1% advantage overall, and that advantage was most likely acquired through practice and skill. It should be strong encouragement that anyone else can do the same thing. 

Madaket PHRF Raceline

We closed the last round of PHRF Hotlaps several months ago as we changed the race courses. When we found out the USS sims would rearrange, we decided to wait longer… it was a depressing time, with several boats crying “test me, please.“    That pile has really grown, and the number of untested boats is now substantial. 

 Well, sportsfans, wait no longer!   I’m thrilled to join with Cynthia Centaur and Fancois Jacques to announce the opening of the PHRF Race Line in Madaket.  The Madaket line is intended primarily for solo sailors, including  PHRF hotlaps or skippers working on their sailing skills. The line will get special attention so that race conditions remain constant, making it easier for sailors to evaluate different racing techniques and allowing them to track their performance over time.

If you take sailing seriously and want to do laps to improve your racing skill, this line’s for you. For exactly the same reasons, if you’re brand-new to sailing and still a bit confused, and think you’re getting addicted and want some quiet time to figure it all out without the pressures of a race director and trash-talking fleet around you,  well… Madaket fits that bill too. The Madaket line is for solo sailors of all levels, with maybe a few match racers thrown in.

So what’s different about the line in Madaket?  I’m glad you asked:

First of all, the Madekat line comes with a guarantee.  Francois Jacques and NYC are the sim owners, and they promise the Madeket line will stay exactly the way you see it now for at least six months. Things change pretty fast in second life, but the new race line and all the parameters will be fixed in place so you can trust the results you get over time. There won’t be any “technical adjustments” because Glida has astigmatism, or weekly squeezing/ stretching the line to accommodate twelve J-Class boats. And, believe me,  you’ll never see the line moved because a resident buys a parcel and doesnt like the raceline view.

This is important since it means that if you do a few laps in February and save the results in the database, you can come back in May and repeat the lap to compare your performance and see where you stand. The line will not change and the data will be comparable. I think many sailors will end up using the line several times a week so they can graphically show the progress of their lap scores with time.

Of course another big advantage of a fixed line is the chance to accumulate phrf lap data to accurately handicap new and older boats alike.

Wind

To keep it simple and error-proof, we are also locking the wind in Madaket, using a single, standard PHRF setting (spd= 11.0m/s and dir=180° (from the South)) with no variance.  A sailor won’t have to waste time resetting and doublechecking the wind.  The PHRF line will always be ready to go. Perhaps much more important, the sailor will never have to wonder whether an upgraded Windsetter or some change in its parameters has subtly affected the lap racing conditions.

 

When you use the line, you should not have to touch the Windsetter. However, if for some reason the Windsetter was shut off, you may need to restart it.  The Windsetter is located next to the red nun on the west side of the line, as shown below. To restart it, type “/44on” within whisper distance of the device. The color should turn from red to blue and you’re all set.  

If you want to so a lap on the PHRF line, first of all find your way to Madaket; its the sim East of Nantucket Yacht Club (shown in the first illustration above). You’ll see the raceline parallel to the southern sim edge. You can rez your boat anywhere in the sim, there’s a 15 minute auto-return. If you’re too clumsy to get your act together in 15 minutes, let us know; we’ll make the autoreturn 16 minutes.

The Madaket PHRF Raceline uses a web-linked database designed by Cynthia Centaur to store and compare lap results.  You’ll find it’s very easy to use, and all the directions and information are contained in a series of posters on the starboard side of the raceline, shown above. If you are confused about any aspect of Hotlaps directions, just click the sign on top (labeled “1.” in the picture). You’ll get a set of detailed directions like this one. “2.” is the display for results and web data, and “3.” is a copy of the race chart shown below.

The Madaket PHRF Hotlaps Course is based on the old “NYC M1 Hotlaps” racecourse. that earlier course was put together by M1sha Dallin and myself specifically for PHRF and discussed for a few weeks in the Forum. We then tested it out in Manning Straight, comparing the data to all previous PHRF courses. M1 proved valid and reliable, similar to all the others. The Madaket PHRF Course is modeled after M1, although each of the legs has at least one additional sim, which should make the lap times correspondingly longer.   

 

Instructions on starting the line

When you are ready to sail a lap, left click the raceline so it will listen to you. (or, if somebody is on the course, it gives you a message that the line is locked).

Shout ” +reset “.
Shout ” + start “ to begin the two minute countdown.

Sail the course.

Posting your good laps on the Web Database 
 

The remaining instructions are only necessary to publish your hotlap on the web display.

PHRF conversions are determined by comparing the average net lap times of different boats on the test course. A skipper should post all of the results that he or she feels represent a typical “good lap,” not just the fastest laps. 

if you don’t save a lap, it will disappear after a few days. if you want to save a lap for the database, however you can do it at any time after the race is finished until the data disappears.

Here are the steps to publish a lap:

After you finish the lap, left click on the red buoy. You will get a pop-up.
Go to the webpage indicated by clicking on the card.
On that opening webpage click “laps (open and closed)”
Put a check in front of the lap you just completed.

 you may see additional blank data fields.  if so, add the specific information requested, such as the name of the course you sailed (“PHRF Course” for example) and then click “Publish.” 
It is just that simple!

PRHF Comparisons

 as PHRF lap scores get added to the database, I will start posting tentative comparisons and hopefully start some discussions about differences between the boats and possible factors that explain them. Last year saw several surprises in the results, so I’m betting this is going to be fun.