C-Dory25 in 5-7ft Seas (~10ft when stacked) My 1st SeaTrial

[Delphinus]

Just wanted to report that my C-Dory 25 Cruiser did great in 5-7ft seas with occasional stacked waves reaching ~10ft. Waves were fairly steep but not breaking (white-caps everywhere) with periods of about 5 seconds.

Early afternoon, on May 25, 2013, my step-father and I launched from Cape May, NJ, and went out into Atlantic about 10-12 miles. We were at the north-east edge of mouth of Delaware Bay (contributed to increased fetch). West winds were sustained at 20-25mph with 35 gusts (small craft advisory). The previous day winds had been 25-30, with gusts that qualified for gale warnings. Therefore, winds had been sustained for days. This was the roughest he and I had ever experienced in a small boat. He has considerable boating experience and I have a good amount. I needed to know I could trust the seaworthiness of my newly purchased C-Dory 25 "Dori Den" (after sons Dorian and Denny). My previous boat was not sufficiently safe for my family, even in much calmer conditions.

Heading east, 11-14knts, Dori Den surfed well and fast... almost too exciting... had to be careful not to have bow driven into wave ahead. Heading west, 4-5knts, took waves slightly off bow... kind of tacked, by alternating port and starboard, to keep from falling off waves and slamming, and to keep props in water. Noticed that wind would grab bow at top of waves and turn us, so constantly had to point bow back into waves. Took one stacked wave over roof from port side (not breaking) since didn't swing bow back around fast enough...short period between waves. Took a few stacked waves over bow and onto roof. Never had much water in cockpit. Was clear to us that most open boats of similar size would have been in much greater danger.

Saw dolphins and a large sea turtle (about 100lbs). The latter stuck it's big head out of the water and watched us for some time as we charged the waves...no faster than it could swim. I love my C-Dory!

[Chester]

Welcome to the family!

[JamesTXSD]

Welcome aboard. We don't go looking for rough water, but spend enough time out and about, and there will be situations that ... um, increase your confidence level with these boats and expand your experience.

Interesting first post about your first experience with the boat. Easy cruising, fishing, and handling the rough stuff - these boats do the job!

Best wishes,
Jim B.

[DuckDogTitus]

very cool, I wish you had a gopro camera mounted on your boat for that experience.

[Delphinus]

Chester, jim an Joan...Thank you for the for the kind welcome! I have learned so much from the C-Brats website over the past year that I wanted to contribute what I could.

Want to be as accurate with details as possible. At 3:00am, morning of same day, Cost Guard predicted 4-6ft seas and winds as described above. Once we got several miles off shore, steep rollers got taller than when only a few miles off shore. Determined that land had partially blocked west wind. Seemed to us waves were 5-7ft (tallest ever been in) no way of knowing heights of occasional big ones (presumed stacked) except they would dump water on roof...so guessing 8-10ft. When hit on port side by what seemed to be a 7-8 footer (described above), water covered windows and some went onto roof. That was most concerning wave for us because it only takes a wave one-third length to capsize. However, I didn't get feeling we were in danger. We did not roll as much as I did when my previous boat (Catalina 25 swing-keel sailboat) was hit by a ~6 footer on the port beam several years ago. Maybe sliding due to flat bottom or greater buoyancy of C-Dory accounted for greater stability (aware that initial stabilities of sailboats less than power boats, with terminal stability being greater). For what ever reason, felt safer in C-Dory.

Went out again on following day (26 May). West winds reported to be 15-20, with gusts to 30. Again "small craft advisory". (Important detail missing: don't remember if marine forecast was reporting winds in mph or knots...even though I said mph above, might have been knots...sorry for imprecision.) Went west out of Cape May channel this time straight into bad inlet chop...easily 4 footers, steep, periods 5 sec or less. Went around southern tip of Cape May, then north for a few miles. Then turned east and back out to sea. Maintained a heading of 105 degrees until reaching position of 38deg 57' N -74deg 32' W. We were out of sight of tallest structures on land and approx 18 nautical miles from shore based on position calculations. The ocean was not as challenging as previous day...and absolutely beautiful. Average waves ~4ft. We did last radio check to Coast Guard Base Cape May, and put engines in neutral to see that C-Dory points down wind due to much forward windage (cabin acts like sail). Had beautiful jog back in at about 5knts...tacked in...taking waves at ~45deg with net heading of 285deg. Our C-Dory 25 Cruiser, "Dori Den", was wonderfully safe and sea-trial tested...as were its operators. And the girls (as we refer to our twin Honda 90s) purred all the way home.

[Delphinus]

Thanks, Dustin and Christina...

In retrospect, I really wish I had a camera too! I was actually a bit nervous on first most exciting day and was just praying we and the boat were up to the challenge. We had removed things from the boat that could be tossed around. Went bare poles too...with bimini down and poles forward and taped together and taped to aft cabin hand rails/grips.

One thing that really helped stabilize the rider in the passenger seat, or when standing, was a 4-5ft length of half-inch line attached to the inside, port-side, ceiling hand-rail. When sitting in passenger seat and brought over shoulder or under right arm (or when standing), and held with both hands, kept passenger from being thrown around.

Thanks for your input. Best wishes

[thataway]

Welcome aboard--and good seamanship! Yes, the C Dory being a fairly flat bottom will slide sideways in beam seas. I think it would be hard to capsize one unless in the surf (which did happen to the only one I know of which capsized). The dynamics of a sailboat are different--and I have taken a 90 degree roll in the North Atlantic in 40 to 45 foot seas--beam about 14 feet. (The sail area up was only about 10% of working sail area, and was enough to keep the bow down wind, but the seas were confused and from several directions.)

There are 3 major factors which determine wave height: wind velocity, fetch (distance the wave travels) and duration. There are minor factors, which include latitude, depth, type of water, other wave trains etc.

We can estimate waves, but today, fortunately we have offshore buoys which measure wave height and period. It sounds as if you were in some nasty stuff, and you ran your boat extremely well.

[Delphinus]

Thank you Bob, for your kind complement and excellent experience-based assessment! I forgot to mention that water depth ranged from 25ft-40ft. Very glad to hear your take on beam seas...you explained very well what I felt that day. Also, very happy to hear your confidence in C-Dory's ability to handle beam seas...especially if caught in confused seas and unavoidable.




I WANT TO THANK ALL WHO SO KINDLY RESPONDED TO MY POST(s)!! I must bid you farewell, for next several days, as am departing for next adventure

Very Best Wishes for SAFE and HAPPY Boating!
Sincerely,
Gerry
of "Dori Den"

[hardee]

Gerry,

Welcome and enjoy.....the TWINS, for sure. The C-Dory will handle more than most folks are comfortable with. Unlike a sailboat, I doubt they will recover from a 90 degree roll, but they are sure fun the rest of the time.

Harvey
SleepyC

[hardee]

Gerry,

Welcome and enjoy.....the TWINS, for sure. The C-Dory will handle more than most folks are comfortable with. Unlike a sailboat, I doubt they will recover from a 90 degree roll, but they are sure fun the rest of the time.

Harvey
SleepyC

[Delphinus]

Thanks for the welcome, Harvey... I agree, twins do add a measure of confidence!

Also, want to thank Bob again... for making me aware of and appreciate what great resources off-shore buoys are!

In interest of being as accurate as possible, in my above account, as would hate to exaggerate capabilities.
Google search of "Cape May Off Shore Buoy" gave the following:
National Data Buoy Center (NDBC) Station 44009
Buoy location: 38deg 27' N - 74deg 42' W (very near our position)
Buoy Data...
Yr: 2013
Mo: 05
Dy: 25
Hr/mm: 1300
Wdir(degT): 290
Wspd(m/s): 13.0 = 29.1 mph
Gst(m/s): 16.0 = 35.8 mph
WvHt(m): 1.8 = 5.9 ft
SwH(m): 0.2 = 0.7ft
Dpd(sec): 6
Apd(sec): 4.8
Mwd(deg): 346
Steepness: very steep

This certainly took the guess work out of it. It appears our above estimates were fairly close. My only remaining question... how does one estimate max wave height?

Unfortunately, I must depart for several days and will not be able to get messages... However, I GREATLY APPRECIATE ALL OF YOUR INPUT!

Sincerely,
Gerry
"Dori Den"

[thataway]

I would say that Gerry has a very good eye. With the 5.9 feet this will be the average, and there are going to be some "summation" waves, which will be as much as twice as high on occasion. The period is also very short, so thus the "very steep". Most people over estimate the size of seas--but not so in this case.

The wave is measured from bottom of trough to top of crest. Figure the height of your eye at the helm, and then the amount above or below that to the crest when you are in the trough. Experience is probably the best way to judge height, and compare what you think to the buoy reports.

NOAA gives the height from trough to crest, although I have seen others say half way up the wave, implying that "sea level" is half way.

Also NOAA defines as: "Seas and waves are expressed in the terms of the significant wave height, the mean or average height of the highest one third of all waves in a swell train or in a wave generating region. It approximates the value an experienced observer would report if visually estimating sea height. "

[rogerbum]

See - http://www.vos.noaa.gov/MWL/apr_06/waves.shtml .

These are approximations that are based on "typical waves" but:
A significant wave height of 6ft. will have a mean height of .64*6 = 3.8'. 10% of the waves will be 6ft *1.27 = 7.6' and 1% of the waves will be 6*1.67= 10ft'. With a wave period of 6s. You'll encounter 100waves in 600s = about 10mins. So every 10 mins or so, you have one of those 1%-er waves that go 10'+.

[Delphinus]

I sincerely want to again thank Bob (of Thataway) for his kind complement and excellent wave assessments/definitions... and Roger (of Meant to Be) for his very vaulable definitions and formulae for calculating highest 10% and max 1% wave heights and duration between max occurences. Advice I have received here will be entered into my log book for future reference while underway.

I am compelled to mention that I have been given more credit, for seamanship, than I am due. I MUST RECOGNIZE THE ENORMOUS CONTRIBUTION OF MY STEP-DAD, RICHARD RAUDABAUGH, FOR HIS VAST BOATING EXPERIENCE, ADVICE AND POISE DURING OUR ADVENTURE... WE SHARED THE HELM EQUALLY! WITHOUT HIM, I WOULD NOT HAVE HAD SUFFICIENT EXPERIENCE AND CONFIDENCE TO MEET THE CHALLENGE! WE WERE A GREAT TEAM!

Very Sincerely,
Gerald Ballough
(Gerry of Dori Den)

[Sea Angel]

Gerry;

Welcome aboard!

Great account of the CD-25's ability, but more so of a your 'seaman's eye' and helm skills.

What you described reminded me of our 2006 Langford Gathering return run back to our home port in Va. Beach. I really appreciated my '25 with the twin 90 HONDAs on that trip.

I'm looking forward to your future stories.

Art