Surveying the Hull
Surveying Fiberglass Power Boats
by David Pascoe
Surveying the hull of a yacht should consist of three distinct parts: interior, exterior and sea trial.
This is necessary because the overall survey process proceeds in three distinct steps, and does not provide the opportunity to complete it all at once.
The exterior portion, of course, is done at the haul out. In the previous chapter it was suggested that the examination of the hull from the interior while the vessel is underway is essential in determining whether a hull is truly sound. This chapter will explain why.
The order in which the various elements of the survey are carried out is important but not always under the control of the surveyor.
The ideal scheduling would be to open up the interior and make the internal hull inspection first, followed by hauling and then the sea trial.
The reasoning here is that any indications of problems showing up on the internal and external inspections could then be evaluated during the sea trial as to their net effect on the actual structural stability of the hull during operation, rather than merely guessing what the effects would be.
It's always best to approach a hull survey with a coherent plan in mind rather than on a helter-skelter basis.
Having a set of plans is most helpful but a rare occurrence. Even so, more and more yachts builders are providing a variety of plans and diagrams packed into their owners manual.
Before starting, ask for the manual and quickly page through it to see what kind of information is provided, particularly schematics.
Before getting started, I like to make a general tour of both the interior and exterior.
On the outside I look at whatever part of the hull sides I can see, along with briefly examining the hull/deck joint. Here I'm looking for any signs of disturbance which might suggest that the hull is working or wracking.
Guard rails that are buckled or exceptionally loose, cracks along toe rails, stress cracking on the superstructure, unfairness or bulges on the hull sides, all of these things may be indicators that all is not well.
Signs of trouble on the exterior can alert us of where to look on the interior, save time and avoid errors.
On the interior there is a lot more to look at even before opening things up. In the heyday of wooden yachts, it was de rigeuer for surveyors to examine the interior for evidence of hull working. Wracked hulls always showed up signs of disturbance on the interior.
Today, these techniques are still useful. How doors line up to jambs, loose moldings, buckled wall coverings, counter tops with large gaps, evidence of pieces of wood or other materials that are working and abrading, unusual gaps in woodwork or paneling may all be signals that the hull is not as stiff as it should be.
When we find such evidence, this is our que to pay extra attention once we pull up the hatches and start crawling around in the bilge.
(Additional spaces are added for easy screen reading.)
Table of Contents: Chapter 6
6. Surveying the Hull 143
Hull Numbers 144
Internal Hull Inspection 145
Evaluating Structural Design 149
The Great Unseen 150
Sawdust and Debris 151
Hull Bottom and Sides 156
Termites & Other Pests 157
The Hauled Survey 158
Sighting a Hull 159
The Keel 162
The Running Gear 162
Stern Drives 164
Some Things You May Not Have Thought About 165
The Deck Joint 165
Mr. Blister 167
Sea Trial 168
- 2nd Edition
by David H. Pascoe
Publisher: D. H. Pascoe & Co., Inc.
David Pascoe - Biography
David Pascoe is a second generation marine surveyor in his family who began his surveying career at age 16 as an apprentice in 1965 as the era of wooden boats was drawing to a close.
Certified by the National Association of Marine Surveyors in 1972, he has conducted over 5,000 pre purchase surveys in addition to having conducted hundreds of boating accident investigations, including fires, sinkings, hull failures and machinery failure analysis.
Over forty years of knowledge and experience are brought to bear in following books. David Pascoe is the author of:
- "Mid Size Power Boats" (2003)
- "Buyers’ Guide to Outboard Boats" (2002)
- "Surveying Fiberglass Power Boats" (2001, 2nd Edition - 2005)
- "Marine Investigations" (2004).
In addition to readers in the United States, boaters and boat industry professionals worldwide from over 70 countries have purchased David Pascoe's books, since introduction of his first book in 2001.
In 2012, David Pascoe has retired from marine surveying business at age 65.
On November 23rd, 2018, David Pascoe has passed away at age 71.