Log of SV Free Spirit and ships company

The chronicles of the schooner Free Spirit and her crew, embarking on an open ended journey upon the great rolling heap. Free Spirit is currently pursuing humanitarian and commercial goals in the Dominican Republic, on the island of Hispaniola. Working under the Ocean Reach USA and Paradigm Research banners, she is serving as logistics headquarters, workshop, and development laboratory for many ongoing projects. This is the log of her journey.....

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Books and more, at the Schooner Free Spirit Chandelry
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Saturday, April 29, 2006

Back to Alaska

With bittersweet finality, my San Fancisco sailing adventure draws to a close.

We're in the airport awaiting our flight,and as I reflect back on the last few weeks I am both glad to be headed home, and sad to leave the cruising grounds.

I have had many adventures, made new friends, renewed old friendships, and learned many things that will stand me in good stead in the future. Be sure to read the posts below detailing our many misadventures on the way, but for now I look foreward to being with my family and the many comforts of home.

Fair winds, gentle reader, and thank you for visiting!

Suisuin Bay to Owl Harbor

The run from Suisuin Bay to the marina at Owl Harbor began mercifully late at around 1100.

The tide had slackened, and we were rested from the last nights adventures. (see the next story, below) We set off on a starboard reach South from our anchorage at the Northwest point of Sherman Island. When we turned east onto the San Joaquin, our relative wind became so weak that we decided to motor-sail up the river, at least for now. With the doddering 34 year old outboard pushing us onward as best it could, we made good four knots over the bottom. We had previously discovered that this motor prefers not to work too hard, so we were limited to about 1/4 throttle excepting short bursts of "war emergency power".

After we crossed under the big bridge East of Antioch, the breeze began to freshen and we cut the motor as we turned onto a port reach to the Northeast. Fortunately this time we wouldn't be running from the law like the last time we were here, as the rain upstream had subsided and the delta was reopened. The revelations divined from the book of wishes turned out true (no doubt due to the sacrifices) and we had a fair current the whole way, often making over 6 knots over ground upstream, though our waterspeed probably never got much higher than 5.

After a beautiful and relaxing trip upriver (often looking down on the surrounding farmland, an odd sensation) we finally turned the bend that marked the entrance to Westward's permanent berth. Entering the narrow channel to the marina, we took down sail with perfect timing and motored (a guilty pleasure after watching the engineless Knarrs) into our berth at about 1600, well satisfied in our accomplishments.

I'm not telling what happened the next day, though I will hint that Westward performed handsomely in her short career as a cable laying ship. By the way, the crab cakes upriver at The Riverboat are quite edible, and the homeward beat upwind in the dark was challenging if uneventful.

Midnight madness at Spoonbill Creek!

Our departure from San Francisco really began the previous day, with a trip to town to provision with victuals and a short jaunt to the gas dock to fill up a fuel jug. We slept soundly that night, awaiting our sunrise departure. At about 0730
(not quite sunrise, I know)
I rolled out of bed, Raised the main in the almost calm air, and cast off lines.

The engine was running fine, but the boat seemed sluggish in reverse. Powering off the T slip, I became a little more than a little concerned when the propwash aft stopped and we started to drift down on a beautiful Knarr with our anchor leading the way toward the hand polished finish. "CIM!!! Need you on deck, right now" Cim bounced out of bed and was on deck before he knew it. We gently fended off and slowly gained way under the main, ghosting out of the harbor in the mirror smooth water.

The shear pin on the outboard had split, for reasons unknown. As we sailed across the bay, I replaced the pin and we began to motorsail across the shipping lanes into Raccoon Strait. About halfway through the strait the motor unexpectedly quit, and we ghosted the rest of the way through with help from the tide. After much head scratching, I decided that the motor worked fine at medium - low throttle settings, but would quit at higher settings after about 20 minutes. I ruled out fuel starvation - the obvious answer - and I'm still not sure why it doesn't like higher power settings. It could be just that it's thirty some years old, the pistons fit as tightly as a dime in a quarter roll, and it just doesn't feel up to it any more. Geriatric perogative - as long as you keep the throttle down it can go all day.

The wind began to fill in around 1030, and we ran wing and wing up through the San Pablo Straits with suprisingly little traffic to dodge. Our easy run continued through the afternoon, and we made to the mouth of the Carquinez exactly on time to make the tide. Putting Carquinez Strait behind us we reached North-Northeast to the spot in Honker bay where I had anchored on the way south, and settling in for the night we dropped the hook at 1700. Quietly, while we played cribbage, Loki slipped into the cabin unannounced.

Consulting the tide book, I saw that we could, if we left in an hour or so, make the tide change in new York slough (6 miles to the east) by sailing against the slowing current. The tide information cheerfully suggested that the tide would carry us through once we got there, and we might well enjoy a comfortable anchorage on Fraser Shoal for the night. All that progress for just a little night sailing, and besides it was a shame to waste the good wind. The forecast was for calm through the night, and weaker winds the next day. We were concerned that we might have trouble fighting our way upriver, and with the motor being so picky I thought maybe we should sail while we knew we could.

We pulled the hook as the current dropped to less than a knot, and we sailed strongly with the sunset at our back. Soon the darkness fell, as did the wind, and we made slow progress downwind.

I'm not sure when it was, exactly, that I began to refer to the tide book as the "book of wishes".

Despite rosy tide predictions, the current was turning against us. We slowed to half a knot, still a mile away from the fabled slough, and we could see (even in the dark) that we would not be soon entering the land of fair currents. I decided that we should bear north and head for Spoonbill creek for the night. It looked well protected, shoal at each end to keep anything too big out, and wide enough to anchor out of the channel. With the wind almost gone, as forecast, and Spoonbill creek flowing gently north, I felt good about our decision. After all, we may not have made Sherman Island, but we were closer than we were, and still enough time for 6 hours sleep before 0600. We anchored fore and aft with two anchors, bow to the mild current, and drifted off to the sound of frogs.


I jumped out of my berth, and looked out aft to see us pinned against the rip-rap levee wall by a 5+ knot current from astern, and a 20 knot wind from the west. Briefly surveying the situation, I woke Cim and began to attempt an extrication. The rudder was jammed -I was not sure whether by debris or damage - but knowing how strong Westward was built my money was on debris. I tied the stern anchor rode off to a float and cast it overboard.

Despite our attempts to swing toward the channel center, the jammed rudder and the relentless current conspired to pin us against a trash fence for a nearby aqueduct. It was 0130. High tide. We had to get off the levee wall, or we would be trapped as the tide went out. If we dried out here on the steep rip-rap wall, we would probably be tripped by our keel, fill and sink when the tide came in.

I directed Cim to tie the now slack main rode off to a corner post on the trash fence. With heroic effort, he dislodged us from the fence, and helped me warp ship until we hung by the bow from the post. I worked the rudder until the debris cleared, the unseen culprit washing cleanly away astern into the blackness of the night. With our spirits renewed along with our rudder, we motored up on the post, cast our line off it, and retrieved our anchor.

Confident that the current would hold at least for a while, we dropped the hook in the channel center and I maintained an anchor watch while Cim slept. I had the tiller tied over, and occasional adjustments kept us near the middle using the current to hold us against the wind.

As the current slackened, the wind increased. By 0315 I was unable to keep us away from the rocks, so I wakened Cim. We pulled the hook, retrieved our wayward stern anchor, and set out for Sherman Island with renewed faith in the "book of wishes".

You see, during my anchor watch, deep truths from the book were revealed to me. Following the still small voice from on high urging me to "read, read more!!!" , I discovered the tome of currents, the very scripture that would have foretold the ugly events of that early morning.

With faith renewed and wisdom increased, we used the now favorable currents and winds to easily fetch the anchorage off Sherman Island. Wide, protected enough, and with excellent holding, we knew that we would be secure for as long as we chose to stay. Armed with the knowledge that we could rest comfortably until our "ideal current" departure time of noon, we slept the sleep of the enlightened, and I dreamt of fair island maidens.

Tuesday, April 25, 2006

Internet Explorer Technical stuff.....

Due to the increasingly proprietary nature of Internet Explorer, it is getting more and more difficult to write pages that display correctly in all versions of IE.

Many web publishers aren't even going to try anymore. Increasingly, If you want to view many web pages correctly, you will have to switch to Firefox, Opera, or one of the other industry standard web browsers. (Not even to mention the popups, spyware, and virus scripting issues with IE)

There is more at stake here than many realize. In their soon to be released OS, Microsoft is rumored to be exploiting the ability to block or sidetrack websites from being displayed with their browser. Think clicking on Google and ending up on MSN search by default. Want to go to the CNN website? Try MSNBC instead! Click on Yahoo, get MSN Messenger. Not pretty, but if nothing is done, that's where we are headed.

I recommend Firefox. I have provided a link for upgrading for IE users at the top of my page, and will no longer be bashing my head into my laptop trying to write for IE users, so please switch if you haven't already, you won't regret it!

Thanks, and happy surfing!

Crew Change

Raoul has gone back home to Fairbanks, and I have been joined by world famous Iditarod Dogsled Race veteran Cim Smyth (who also happens to be my brother) for the trip back up north to Owl Harbor. While fairly new to cruising, Cim has fished the tough waters of Bristol bay and was one of my early experimental sailing students.

We leave early tomorrow morning, taking advantage of the big tides to give us a push north on what is forecast to be a rousing beam reach followed by brisk downwind sailing the rest of the way. (I'm not holding my breath)

We took Westward out for a short sail yesterday, as well as getting some fuel today, so Cim has had at least a bit of a chance to feel his way around the boat.

For any of you adventurous single ladies out there, Cim is looking -He'll probably bust my chops for posting this- but If you like a real man, adventure in the outdoors, intelligence, and enjoying the warmth of a fire in the wintertime, you should track him down!

Saturday, April 22, 2006

SF Cruisers guide to pizza!

The next time you tie up at the municipal marina (Marina Green) while you do your laundry and have a cup of coffee on Fillmore street, (see Cruisers notebook - San Francisco) stop by Pizza Orgasmica and sample one of their excellent pies.

They are available by the slice or in full, thick or regular crust. I would recommend the flagship "orgasmica" or the Canadian bacon and pineapple in thick crust, both excellent.

While not the cheapest you will find, the pizza is excellent, far superior to the other dine in / take outs in the area - and just across the street from the coffee house with free WIFI.

To get there, walk or take the 30 to Fillmore, then ride the 22 up the hill (or walk the whole way, about 1.25 mile from the marina) to Fillmore and Pixley.

Bon Appetit!


In 1943 under the black gloom of war, the Knarr was born in Norway.

Designed by Erling L. Kristofersen, approximately 150 Knarrs were launched in Norway over the next 25 years, and she became the most popular boat of her size in the region.

Today, the Knarr fleet numbers approx. 120 boats in Norway, approximately 50 in the USA,
and well over 120 in Denmark. In 1954 she was approved as a national one-design class
in Denmark. Borresen's yard in Vejle, Denmark, is the only licensed builder of the Knarr,
with a production so far of more than 160 yachts, since 1974 built in fiberglass.

The Beautiful wooden Knarr Sophia is berthed next to my slip in San Francisco, and this morning I had the opportunity to talk with her crew about her history. Her keel was laid 1963, and she has undergone a couple of refits since, including a complete rebuild from the rail up. She is now in beautiful condition and is lovingly cared for by her crew, daysailing and racing in the bay.

Credit must be given to those who, like the crew of Sophia, keep little pieces of our history alive through their passion and dedication to the task. It is a minor credit to humanity to see works of art such as this little Knarr out sailing as living history, rather than collecting dust in some cryptlike museum - keep up the good fight, lads!

Friday, April 21, 2006

Cruisers notebook - San Francisco

San Francisco is an excellent stop for cruisers on the West coast of the Unites States.

The Marina Green municipal marina (Stone tower, 37 48.482N 122 26.395W 415-292-2013 showers) at Scott street and Marina boulevard has transient slips (up to 30 days) for fifty cents a foot per night, reservations recommended for August - October. This marina is cash or check only. There is a $50 key deposit, and a $150 deposit for a power adapter if needed.

There is also a larger yacht harbor to the Southeast (37 46.791N 122 23.162W 415-495-4911 showers, laundry) where berths can be had for $1 a foot - reservations recommended.

Overnight moorage can be had when available in front of the Maritime museum, (aquatic park 37 48.51N 122 25.46W) in the bowl shaped harbor just to the west of Pier 45 Check in at the small boat shop there in the park or Hyde Street Pier.

Don't bother to rent a car unless you plan to leave the city - it is simply unnecessary. If you have them, bicycles with baskets are most convenient, and the busses have bikeracks for the longer hauls.

The municipal bus system ($1.50 includes transfer) is excellent. Get a route map ASAP. Busses on most routes come by at 5 - 15 minute intervals, and there is a grocery store at Beach and Buchanan that is very accessible from the Marina Green municipal marina by a short bus ride or walk. The busses run both directions, so to go back just cross the street and find a bus shelter or the yellow band painted around a streetlight. The route numbers will be marked, so be sure to check.

For a budget tour, get on the 30 (Divisadero and Beach, near Marina Green, or 3rd st and Townsend if you are at South Beach harbor) and take it south through Chinatown. Hop off in Chinatown (you will know when you are there) and buy a foldable rolling grocery basket at one of the many "Trading Co" or hardware stores - $15 or so, you will not regret it! Still hungry? See the lamposts painted with red green and white bands? Hop off in little Italy for a delightful meal at one of the many restaurants and cafes. On the way back check out the Maritime Museum (2 blocks north from north point and Hyde) and while there pick up a transit map if you don't already have one. From there, a short jaunt east takes you to the fisherman's wharf, home to a bounty of restauraunts and touristy shops, as well as a fisherman's marketplace.

For variety and general shopping, restaurants, clubs, coffee houses, etc the northern part of Fillmore Street is perfect. Bus 22 is your ride up and down filmore, and you can catch the 30 at Filmore and Chestnut.The neighborhood is clean and welcoming, even at night. At Pixley and Fillmore (NE corner) there is a coffee shop with free WIFI and good coffee. A few blocks north on the east side of the street there is a coin-op laundry with free WIFI as well.

For further exploration, the river delta to the northeast has over 1000 miles of canals and waterways, right in the middle of Californias wine country. Countless small towns and marinas dot the map, and Sacramento can be reached upriver as well.


Seemed like an appropriate day to visit Haight-Ashbury, so I did. Once arguably the counterculture mecca of the USA it is now largely commercial, though much of the "aroma" lingers. College students abound, with head shops and grateful dead posters following with a close second place tie. The Kind was ever present, and there was even "public service smoke" being blown into bubbles floating down the street by an automated contraption apparently built and maintained by students - how very accommodating indeed! All the eccentric boutiques and shops made me think of my good friend Rachel - this is really her kind of place. Lots of accessories for the budding moviestarlet!

Wednesday, April 19, 2006

City By the bay

Thursday, April 13 0800

My crew (Mr. Raoul Chapman) had arrived the day before, walking in from the rain that had been soaking the already drenched California Delta for weeks. We set forth from Owl Harbor the following morning, with the good omen of a rainbow under a red sunset the night before. Winds were light and variable, so after backing out of our berth we cut the motor and ghosted out under sail. Our destination - San Francisco - lay some eighty miles to the West and South. Pleasant sailing conditions made for a relaxing day as we worked our way down the river, with an unspecified stop planned to provision along the way.

We raised Antioch some four hours later - under power as the wind had all but quit us - where we were informed that on this side of the river, recreational boating had been suspended due to the rain weakening the aging levees against wakes from passing boats. The fine if we were caught sailing on that side of the county line was a stiff $1000 , and if the sheriff's department caught us, there would be no warning, just straight to the fine, thank you very much - or so we were told. Since Westward ghosting along makes less wake than a duck, we chose to disregard the prohibition and trusted in our ability to slip through the fingers of the law.

We walked into town and provisioned - food, ice, hardware, stove fuel, etc - and returned to the marina just after closing. We scraped off Westward's registration numbers and replaced them with our new Alaska registration, loaded our stores and made haste across the river to the county line - home free! There was no wind, so we motored on up to Honker Bay where we would drop the hook and wait for the daylight and tide to slip through the Carquinez Straits.

The next morning came with rain and wind on the nose for the straits. Raoul pulled up the hook about 0700, and we headed out into Susuin Bay for Carquinez. We made good time with the following currents, and entered the straits with excellent timing. There was plenty of shipping, but a little vigilance and planning kept us well out of harm's way with Raoul's excellent helmsmanship as usual. Coming out of the straits into San Pablo bay, we set the sails and secured the motor, making a close reach to Pinole Point.

By the time we reached the point, the current was just turning against us so we ducked in and anchored off the old pier. Time for lunch, some battery charging, and a game of cribbage. When the current slackened, we set all sail flying for San Francisco bay- a slog to windward of course. The wind was brisk out of the south - straight up San Pablo bay, and we welcomed the opportunity to put Westward through her paces.

As we approached San Francisco bay, the traffic became heavy, as did the wind. With 20-30 gusting 40 forecast, we were pleased to find 15-25 gusting in the 30's an acceptable alternative. This touch of hard weather quickly revealed the strengths and weaknesses of the ship, as hard weather always will. She has an easy motion and is very seakindly for her size. She takes beam seas with aplomb, merely rising and falling with hardly any roll at all. She is tender. The reefing on the main had not been properly sorted out, and this was a serious issue for us as even without the jib she could barely stand up to her rig in these winds. There were issues with the mainsheet routing. Her recalcitrant captain had failed to practice reefing the new main in the harbor. Nonetheless, we were committed now, and there was nothing to do but press on.

Though overpowered, thanks to Raoul's careful helming we were never really knocked down in the gusts. We beat our way to the east of angel island, and with the wind backing to the southwest clawed in to find her lee. Out from the island the stronger winds were tripped down to the water by the summit. These "milliiwas" were in the high thirties or low forties, and we were forced to reef the untested main in order to close with the island, no mean feat at 40 - 50 degrees of heel. With Raoul carefully pinching the main as best he could, I managed a jury reef that would allow us to stand into the little tempest. In the gusts the wavetops would sometimes blow off to clatter into the sides of the hull, greatly adding to the drama of the moment. Finally in the calm lee of the island, we dropped the main, set the hook, and went below for some much needed rest. We were soon rewarded with the glowing skyline of San Francisco under a full moon, and we slept the sleep of mariners.

Checking the anchor occasionally throughout the night we woke to another blustery day, less angry than the day before. The chop was down, and the winds were 10 - 20, on the nose of course. We had a exhilarating beat across the remainder of the bay, this time with proper reefs and an improved mainsheet. There we reveled in the view of the Golden Gate, several tall ships, and a veritable cloud of sail on the bay. In a short time, we were entering the breakwater for the municipal marina where we found a comfortable berth for the good rate $.50 a foot. Having raised San Francisco from the horizon and now just footsteps away from her parlour, our thirst for revelry and the many comforts of the city was quickened.

If it was revelry and comforts we wanted, the city was destined to provide in full suite. We were invited to our friend's club for the evening, and we came out to find "bunnyfest", a rabbit themed rave - party thumping along nicely - the place was really hopping. Mostly present were the Burning Man crowd, and it was a great time to be had by all. Equipped with bunny ears and painted on whiskers, we embraced the human current well into the ebb of the morning.

San Francisco

Honker bay to Angel Island

Sunday, April 16, 2006

Owl Harbor To Honker Bay

Sunday, April 09, 2006

Maiden* voyage

Here you can see Westward with her sails hoisted for the first time *since I have known her. The jib came from a nautical flea market, and the main is a recut racing sail.

They fit well, so I took her out for a little sail! I went about 1/2 mile down toward the river, then back - just a little spin to get a feel for her head in a breeze. She sails quite well, but is a bit tender - I'll be putting some sandbags in her bilges to see if that firms her up a bit. She's a bit of a handfull to singlehand in the narrow channel, so I was forced to make my landing under sail - a good piece of show - seamanship, handily executed if I say so myself. It felt great to sail neatly into my slip while the catalina 27 astern motored into hers, sails and head hung low in shame! (If there was a choice, I'd have motored in too, but its better if I pretend that was my plan all along.)

Harrrr! lets see ya do that, ya lilly livered scoundrel!

The Good...

Well, Im here! And the work is all but done. I hope to be sailng Monday!

Still to do:

Bend on the jib
Check battery capacity
Finish laying on stores
General clean up
Check bottom condition

The Bad

When I arrived, Sacramento was flooding. There had been much more rain than usual, and some areas of the city near the river were under six or seven feet of water. Thanks to good planning, the city per se was minimally affected - just don't try telling that to the folks sleeping on the park benches!

Upon arriving at Westward's berth in Owl Harbor marina, I could see that even there the water was some six feet higher than my last visit. Aside from some little plants sprouting from her rubrail, Westward looked fine. A quick look inside, however, revealed some minor issues. The poorly designed pilothouse windows had been leaking a bit, rain had soaked two of the cushions, and about four gallons had accumulated in the bilge. One of the cusions was dried, the other was a loss - but thats ok, as there is no place to put the "mystery cushion" anyway.

But then I found.....

The Ugly.

A close up of the rotted area, showing the extent of the damage.

After a precursury inspection, the only major problem found was some pretty bad rot under the port pilothouse window. Yuck! Only one thing to do.... rip it out!! This wasn't really in my plan, but she couldn't go to sea with a weakness such as this. Four days and several hundred dollars later, and wallah! Better than new. Below you can see the stages of work....browse on!

Drying time..

It took two days to dry the water out of the soaked wood surrounding the rot. After it is dry, it will be thouroughly soaked with two coats of west system epoxy to provide adhesion to the repair.


Filled in the majority of the void with 2 oz fiberglass mat saturated with west system epoxy.


Filled in with west system and microballon putty. Kewl, gooey, sticky suff!! Hard to mix - think mixing a cloud with bubblegum....


Finished, at last!

Saturday, April 08, 2006


For those of you curious about my situation aboard the little sloop Westward, these pictures will give you some insight.
First, you see the cabin as seen from the pilothouse. Good sea berths port and starboard, head in the forepeak behind the door. My laptop strapped below the pilots desk, binoculars hanging from a support post. The galley is port and starboard, the teapot is here shown on the starboard half. Note the hanging preventer to keep the pot from heeling too much. The home made paper towel holder is right at home in her workboat - style interior.
As you can see, she is built to a simple and rugged standard. Tristan Jones would be proud, and have her halfway to nowhere by now, doubtless!

Heres to my boys!

Of the things I wish I could change about this trip, the one thing I truly regret is that I could not bring my boys with me. There has been many things to learn in the preparations I have been making, and it pains me to have kept them all to myself. The trials of these few days would have been joys with those smiling faces that look to me as dad. So, boys, heres to you!

Love, your proud father.

Busy busy busy!

Wow! The last few days have gone by quickly. As you may know I'm in California prepping Westward, our 27' sloop. I've not enough time to write now, but soon I'll be bringing you up to date on the work I've been doing, including - engine repair, wood repair, provisioning, equipping, and more! More soon, thanks for checking.

Introducing Propcalc 4.0

Use Propcalc to easily match your hull with your engine, transmission, and propeller
Put the known data in the top fields, then hit the Update button to get the answers.
Results, of course, should be verified by a Naval Architect or qualified surveyor.
Data is provided for three bladed propellers of average type
For two or four bladed props, use the modifiers shown below.

Fill out the fields as follows:

Vessel LWL (ft) = Waterline length
Vessel Disp (lbs) = Vessel displacement
(max) HP = Rated Engine Max HP
Engine RPM max = Engine RPM at Max HP
Engine RPM cruise = Desired or estimated cruise rpm
(Cruise or Max) Kts = Speed to work the calculations for
Slip = Propeller efficience. 45% is average for a displacement cruiser.
Gear ratio = 1: Gear ratio of transmission
SL Ratio Adj. = This value will be added (or subtracted, if a negative value) to the calculated S/L ratio.

Key information:

If the "hp required" is greater than the "cruse HP", you have your cruise RPM set too low for your engine parameters.
If the "hp required" is significantly less than the "cruse HP", you have your cruise RPM set too high for your engine parameters.
If the "hp required" is greater than the "Max HP", then your target speed is too high for your engine/hull parameters.
The S/L ratio is calculated automaticaly based on your input. It can be adjusted if necessary, but normally it should be left alone.
If the calculated S/L ratio exceeds S/L MAX, then the results are likely to be non-predictive. Try a lower speed requirement.
SL Ratios of 1.1 - 1.4 are typical of displacement hulls. Semiplaning or planing hulls can go higher.

Typical propeller slip values:

Sailing auxiliary, barges, etc less than 9 Kts............45%
Heavy powerboats, workboats 9 - 15 Kts....................26%
Powerboats, Lightweight Cruisers 15 - 30 Kts..............24%
High speed planing boats 30 - 45 Kts......................20%
V bottom race boats 45 - 90 Kts...........................10%


it is possible to get irrational answers by irrational input , I.E specifying excessive speed for hull type and length
Any attempt to exceed hull speed (1.34 times the square root of the waterline length in feet) with a displacement hull are likely
to fail unless the hull is extremely fine (multihull) or otherwise exceptional. In such cases, an S/L adjustment would be in order.

2 and 4 bladed props:

For two bladed propellers, multiply the diameter by 1.05, and the pitch by 1.01
For four bladed propellers, multiply the diameter by .94, and the pitch by .98

Vessel LWL (ft) =
Vessel Disp (lbs) =
  (max) HP =
  Engine RPM max =
  Engine RPM cruise =
  (Cruise or Max) Kts =
  Slip =
  Gear ratio = 1:
  SL Ratio Adj. =
  Prop rpm max =
  Prop rpm cruise =
  Pitch =
  Diameter =
  Static Thrust =
  Cruise HP =
  Cruise HP% =
  SL Ratio =
  DL Ratio =
  SL Max =
  HP Required =