Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 13-11-2012, 05:33   #1
CF Adviser
 
Pelagic's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Boat: Van Helleman Schooner 65ft StarGazer
Posts: 6,896
Useful Sea-Trial Tips and Tests

Thought we could start a Thread on certain checks or tests, prospective buyers should consider when they are at the stage of actually Sea-trialing a chosen boat.

For example: Steering test:
I ask the Owner/broker to go (at minimum) half throttle in reverse and do at least 3 figure 8’s, while I am down inspecting the rudder quadrant for any undue movements or stress cracks in the structural steering system.

Reason: What you are doing is simulating rudder forces in a large following sea, which generally put the most forces on the system.

Any other Tips to pass along?
__________________

__________________
Pelagic is offline   Reply With Quote
Old 13-11-2012, 05:56   #2
Registered User

Join Date: Jan 2009
Location: Marathon Fl.
Boat: Columbia 45 / Iroquois 30
Posts: 113
Images: 3
Re: Useful Sea-Trial Tips and Tests

Propulsion - underway

Full power forward then to full stop to full reverse as fast a possible. - On navy ships it was basically slamming it in reverse from a flank bell. but we had a budget to replace the transmission.
Emergency Shut down and recovery from full power. Shut down an isolate as fast as possible including closing of thruhulls. (30 seconds would be a good target)
Idle engine for an hour or so - unassisted. Just drift. This really is a very good test of how well the engine is balanced and tuned. The go to full power for 15 minutes.
Disconnect battery(simulate battery failure)

Steering
hard full rudder at full speed. shift your rudder hard. Complete a Williamson turn at full power. this will also show how the boat is balanced since it should heel quite a bit during the turn.
Complete several times. port first, starboard 1st.
Back down at full do the same rudder shift.

Im working on a dock trial doc to pre-underway everything since on my boat everything is almost totally redone. basically simulate running everything at sea while tied up the dock. I have put the engine under load as well. this also tests how good your dock cleats are attached to the dock itself. I pulled one - turns out it was attached with a deck screw.
__________________

__________________
sushirama is offline   Reply With Quote
Old 13-11-2012, 07:14   #3
Moderator Emeritus
 
GordMay's Avatar

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 31,596
Images: 240
Re: Useful Sea-Trial Tips and Tests

Accept no mysteries!
Determine cause of, and solution to, anything that confounds or worries you.

Some general advice for evaluating any survey report, or answers to your questions:
1. Take my positive comments with a grain of salt.
2. Take my inconclusive comments as negative.
3. Take my negative comments to the bank.
4. Accept no mysteries.
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 13-11-2012, 07:27   #4
CF Adviser
 
Pelagic's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Boat: Van Helleman Schooner 65ft StarGazer
Posts: 6,896
Re: Useful Sea-Trial Tips and Tests

Hi Gord… Brilliant as usual…. Hope you are well!
__________________
Pelagic is offline   Reply With Quote
Old 13-11-2012, 08:02   #5
Registered User

Join Date: Oct 2005
Posts: 341
Send a message via Skype™ to gosstyla
Re: Useful Sea-Trial Tips and Tests

Sea Trials Check List
I. Components, Machinery, Equipment and Systems Tests
  1. All automatic systems to be tested.
  2. Rig tuning
  3. Full load and Prop Match tests of engine
  4. Functional/capacity testing (and adjustments as necessary) of all equipment, instruments and systems (including piping)
  5. Compass calibration
  6. Maneuvering and steering trials, including low and high speed, forward and
    reverse, sharp turns and docking-like maneuvers. Crash stops. Steering should be checked by going hard over to hard over for 10 cycles at 50% and 75% of full throttle, do this by hand and then by autopilot. In reverse, at least 12 times, at 25% of full throttle let steering run so the rudder fetches up against its stops. Back at dock check condition of rudder stops.
  7. Noise level, acoustic privacy monitoring and vibration survey
  8. Motors endurance and speed trials at maximum power. Run motors under power
    for 2 hour stretches at 25%, 50%, and 75% of full throttle. Make a final full speed run for 15 minutes. Check reverse by going from 50% forward to 100% reverse at least 6 times. Obtain recommended test procedures from Glacier Bay.
  9. All electronics switched on and view critically and allowed to operate continuously during sea trials. Also a) Does depthsounder go blank when motors are running; b) Does a VHF transmission cause wavy lines to appear on the radar screen; c) Does the GPS crash when the motors are started;
    d) Is there static in the SSB radio when the genset is running.
  10. Windlass tested under load, i.e. drop anchor.
  11. Use the heads.
  12. Check pressure water system.



II. Sail Tests
  1. Roller Furling and supporting gear.
  2. Mast alignment
  3. Hydraulics
  4. Winches and winch motors tested under load.
  5. Proper number of winch handles
  6. Leads, turning blocks, halyards, whipping, and all other deck hardware
  7. Standing and running rigging
  8. Shroud boots
  9. All sails to be hoisted and inspected for shape and wear and sheet positions and
    adjusted for every point of sail to insure that running rigging is properly placed
    and in good operation order. Check that reefs are correctly placed.
  1. Jam the boat hard in a stiff breeze to determine if stability is satisfactory.
  2. Check above and below decks for proper handholds, movement of bulkheads,
    squeaks and other noises.
  3. Can she tack upwind without jib.
  4. Make a log of suggested sheet positions, twist, and sail usage.
  5. Do a few crash jibes.
Back at dock inspect a) prop-shaft alignment b) all oil, water, and fuel lines for evidence of leakage c) wires and hoses for signs of chafe d) exhaust lines for vibration damage and leaks e) belts for signs of fuzz, or wear on edges f) motors and genset to be sure they are clean.
Tests will be carried out first in optimal wind and sea conditions and then in heavier wind and sea conditions. Following the completion of trials, any item of equipment that is defective, will be repaired or replaced. If major repairs are necessary, the trials are to be rerun until all equipment meets the requirements.
__________________
gosstyla is offline   Reply With Quote
Old 13-11-2012, 08:13   #6
CF Adviser
 
Bash's Avatar

Cruisers Forum Supporter

Join Date: Dec 2008
Location: sausalito
Boat: 14 meter sloop
Posts: 7,260
Re: Useful Sea-Trial Tips and Tests

Quote:
Originally Posted by sushirama View Post
Propulsion - underway

Full power forward then to full stop to full reverse as fast a possible. - On navy ships it was basically slamming it in reverse from a flank bell. but we had a budget to replace the transmission.
Emergency Shut down and recovery from full power. Shut down an isolate as fast as possible including closing of thruhulls. (30 seconds would be a good target)
Idle engine for an hour or so - unassisted. Just drift. This really is a very good test of how well the engine is balanced and tuned. The go to full power for 15 minutes.
Disconnect battery(simulate battery failure)
Regardless of how the navy decides to treat warships, I don't feel that destructive or dangerous testing such as recommended above is a legitimate activity for a sea trial. Only a fool goes from full power forward to full reverse "as fast as possible." As for disconnecting the battery while underway, that's just plain goofy.
__________________
cruising is entirely about showing up--in boat shoes.
Bash is offline   Reply With Quote
Old 13-11-2012, 08:14   #7
CF Adviser
 
Pelagic's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Boat: Van Helleman Schooner 65ft StarGazer
Posts: 6,896
Re: Useful Sea-Trial Tips and Tests

Great list Gostyla
__________________
Pelagic is offline   Reply With Quote
Old 13-11-2012, 08:17   #8
cat herder, extreme blacksheep
 
zeehag's Avatar

Cruisers Forum Supporter

Join Date: Jul 2008
Location: furycame alley , tropics, mexico for now
Boat: 1976 FORMOSA yankee clipper 41
Posts: 17,779
Images: 56
Send a message via Yahoo to zeehag Send a message via Skype™ to zeehag
Re: Useful Sea-Trial Tips and Tests

find out how it sails. if you do not like the way she sails, do not proceed.
zeehag is online now   Reply With Quote
Old 13-11-2012, 08:23   #9
CF Adviser
 
Pelagic's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Boat: Van Helleman Schooner 65ft StarGazer
Posts: 6,896
Re: Useful Sea-Trial Tips and Tests

I agree with Bash…. Only Steam engines were designed for repeated crash stops…
Modern propulsion needs to be reversed with care to avoid damage.

When we do new ship sea trials under Class Survey, (Lloyds) it is discussed and understood by all parties involved that a crash stop is performed "intelligently"
__________________
Pelagic is offline   Reply With Quote
Old 13-11-2012, 08:34   #10
Registered User
 
Sailormantx's Avatar

Join Date: Sep 2012
Location: Newfoundland
Boat: 42' Colvin Gazelle
Posts: 253
Images: 2
Quote:
Originally Posted by Bash
Regardless of how the navy decides to treat warships, I don't feel that destructive or dangerous testing such as recommended above is a legitimate activity for a sea trial. Only a fool goes from full power forward to full reverse "as fast as possible." As for disconnecting the battery while underway, that's just plain goofy.
Bash, crash stops are standard fare during sea trials on.commercial vessels. Determines minimum stopping distance and proves controls are set up right. Sometimes parameters are even specified in the builders contract. On.small boats with mechanical controls you need only to allow rpm's to reduce to idle before reversing, with electronic controls the delay is programmed in.
__________________
Sailormantx is offline   Reply With Quote
Old 13-11-2012, 08:36   #11
Registered User
 
Stray-Cat's Avatar

Join Date: Sep 2012
Location: B.C.
Boat: Chris-Craft 38
Posts: 126
Re: Useful Sea-Trial Tips and Tests

Quote:
Originally Posted by Bash View Post
Regardless of how the navy decides to treat warships, I don't feel that destructive or dangerous testing such as recommended above is a legitimate activity for a sea trial. Only a fool goes from full power forward to full reverse "as fast as possible." As for disconnecting the battery while underway, that's just plain goofy.
+1

I took a brand new $750,000 trawler out for sea trials for a friend
Present was the couple that owned the yacht hull no1 and the Canadian importer
The first thing he said to me before I took the helm was to watch that I waited to go from forward to reverse, as the transmission was not like the commercial vessels heavy duty twin disk I was accustomed to

BTW the boat failed my sea trials
I had turned on all electronics in the wheelhouse and operated both the bow thruster + Stern truster simultaneously and kicked out the wheelhouse nav instruments


That problem was caused by a voltage drop due to a poor design
The bow thruster batteries were located in the stern lazzerette,too far from the thruster

The owners of the vessel had never even done proper sea trials
Needless to say the importer corrected it by adding a pair of batterys near the thruster
__________________
Stray-Cat is offline   Reply With Quote
Old 13-11-2012, 08:49   #12
CF Adviser
 
Pelagic's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Boat: Van Helleman Schooner 65ft StarGazer
Posts: 6,896
Re: Useful Sea-Trial Tips and Tests

[QUOTE=Sailormantx;1083702] On.small boats with mechanical controls you need only to allow rpm's to reduce to idle before reversing, with electronic controls the delay is programmed in.[/QUOTE

I think that actually supports Bash’s premise.
Classification are simply looking for emergency stopping distances to confirm the specified maneuvering data and to see that nothing is damaged in achieving it.
A real crash stop of hard astern with full ramp up is not advised by the manufacturers/builders or expected by Class.
__________________
Pelagic is offline   Reply With Quote
Old 13-11-2012, 09:52   #13
Registered User

Join Date: Jan 2009
Location: Marathon Fl.
Boat: Columbia 45 / Iroquois 30
Posts: 113
Images: 3
Re: Useful Sea-Trial Tips and Tests

I did add "full stop" not a crash reverse. If your boat cant go from full ahead to full stop then full reverse in a few seconds. You have problems. That one maneuver can also expose numerous problems with your drive train. Id much rather find a problem in a controlled test than when I really really needed it. Same for the battery disconnect. Say you have a battery or electrical fire on board and needed to isolate your DC system. Could you keep your engine running and critical systems running with no batteries, alternator only and make port? These arent outrageous situations because they have happened to other boaters.

So why are they outrageous to test in sea trials?
__________________
sushirama is offline   Reply With Quote
Old 13-11-2012, 10:18   #14
Senior Cruiser
 
Cheechako's Avatar

Cruisers Forum Supporter

Join Date: Aug 2006
Location: Skagit City, WA
Posts: 19,375
Re: Useful Sea-Trial Tips and Tests

Quote:
Originally Posted by Bash View Post
Regardless of how the navy decides to treat warships, I don't feel that destructive or dangerous testing such as recommended above is a legitimate activity for a sea trial. Only a fool goes from full power forward to full reverse "as fast as possible." As for disconnecting the battery while underway, that's just plain goofy.
The Surveyor went from full forward to almost full reverse on my Passport 47 seatrial with only a short pause in neutral. It shocked me, but realistically.... not sure I'm convinced its a bad thing... the water can only "grip" the prop so much.
__________________
"I spent most of my money on Booze, Broads and Boats. The rest I wasted" - Elmore Leonard











Cheechako is online now   Reply With Quote
Old 13-11-2012, 10:27   #15
CF Adviser
 
Pelagic's Avatar

Cruisers Forum Supporter

Join Date: Oct 2007
Boat: Van Helleman Schooner 65ft StarGazer
Posts: 6,896
Re: Useful Sea-Trial Tips and Tests

Quote:
Originally Posted by sushirama View Post
- On navy ships it was basically slamming it in reverse from a flank bell. but we had a budget to replace the transmission.
Moving Forward.....I think we all agree that this is not recommended
__________________

__________________
Pelagic is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off




Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 11:56.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.