Copyright 2011 CONRAD YACHTS All Rights Reserved
Hull Characteristics.
Tuna 25 FC hull is identical to  the WA version.
The hull can be best described as a modified constant deadrise form, the most
trusted and well behaved hullform ever developed.
2. Relatively high deadrise at transom(19.5 degrees), makes her much more
comfortable in sea way than the majority of boats this size, whose deadrise is generally
in the 13 to 18 degrees range.
3. The innovative, variable width chine flats are wide aft, gradually narrowing from
amidships forward. The wide chine flats aft give the hull extra lateral stability, while
narrow chine flats forward, allowing the hull to move through the water,  prevent
slamming against oncoming chop.
4. The hull itself is 25 feet long, 27 feet including the engine bracket/swim platform.
Including the outboard engine, the boat is just over 29 feet long.
Tuna 27 FC - #03
Full Cabin
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1. All  major hull structure components are designed and calculated to conform to the requirements of ABS
(American Bureau of Shipping).
2. The maximum beam is 8’-6". This is the legal width limit for a trailable boat in B.C., without special permits.
3. Whenever possible, welds are avoided: entire cockpit sole(from the bow to the engine bracket) is made of only two
lengthwise halves, welded together, then welded to topsides(side plates) around the perimeter, and slot welded to
structural members underneath. Each hull half is one piece, so are side plates. This approach yields a much fairer hull.
4. The hull is framed longitudinally, which, again, produces a fairer hull, eliminating the "hungry horse" look of many
metal boats.
5. The structure consists of longitudinal girders and transverse frames, which “egg crate” into one another to make
assembly quick and accurate.
6. I believe in being able to access and remove the fuel tank, if necessary, even after the boat is completed. This is
accomplished by locating the fuel tank under a “soft patch” in the cockpit sole.
7. Alloys used are all top marine grade 5000 series.
Bottom - 1/4"   - 5086 H116
Sides    - 3/16" - 5086 H116
Cabin    - 1/8"  - 5052 H32
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1. Transom height is 25”. Using the engine bracket, instead of mounting the engine(s) on the transom, allows the
engine(s) to sit a bit higher and further aft of the end of the hull. This improves the "hole shot" and allows the
propeller to work in less turbulent water flow. The use of a 30" leg is not necessary, although possible if preferred.
2. Recommended power for this hull is from 150 hp to 500 hp, single or twin installation.
Tuna Walkaround with a single 300 hp Mercury Verado achieves a speed of 50 m/hr, plus.
3. Custom alterations will be considered (additional and/or different configuration of lockers or seating).
4. Cockpit is self-bailing.
5. Built into the cockpit sole, on centre, is a 50 USG fish hold, with a flush lid, built-in drain and a removable liner.
6. It is possible to make the boat unsinkable(not required legally at this size), by filling the unused cavities under
cockpit sole with foam.
  • Hull length
25 feet
  • LOA
27 feet
  • Beam
8.5 feet
  • Draft - hull only
17 inches
  • Draft - engine leg down
31 inches
  • Deadrise at transom
19.5 degrees
  • Transom  bracket angle
13 degrees
  • Minimum cockpit depth - no rail
31 inches
  • Fuel capacity
125 USG
  • Power - single inboard diesel
150-500 hp
  • Capacity ( people)
  • Approx. aluminum weight
3,000 lb
  • Design displacement
5,500 lb
Assembly Drawings:                          
( for
detailed construction study only )
Digital Package:                                             
  1. Assembly drawings.
  2. Parts list.
  3. Nest.
  4. The use of the cutting files-CNC cutting.     
please enquire
Building kit:                                                         
  1. Assembly drawings.
* Does not include tubing, cleats etc.
** Pending current price check at time of purchase
please enquire