Engineering:Amphibi-Con 25

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Short description: Sailboat class
Amphibi-Con 25
Development
DesignerE. Farnham Butler and Cyrus Hamlin
LocationUnited States
Year1954
No. built125
Builder(s)Mount Desert Yachts
Sailstar Boat Company
Burr Brothers Boats
RoleRacer-Cruiser
Boat
Boat weight3,500 lb (1,588 kg)
Draft4.25 ft (1.30 m) with centerboard down
Hull
Typemonohull
Constructionwood strip or fiberglass
LOA25.42 ft (7.75 m)
LWL21.67 ft (6.61 m)
Beam7.75 ft (2.36 m)
Engine typeoutboard motor
Hull appendages
Keel/board typemodified long keel and centerboard
Ballast1,100 lb (499 kg)
Rudder(s)keel-mounted rudder
Rig
Rig typeBermuda rig
I (foretriangle height)24.00 ft (7.32 m)
J (foretriangle base)9.50 ft (2.90 m)
P (mainsail luff)26.75 ft (8.15 m)
E (mainsail foot)12.17 ft (3.71 m)
Sails
Sailplanfractional rigged sloop
Mainsail area162.77 sq ft (15.122 m2)
Jib/genoa area114.00 sq ft (10.591 m2)
Total sail area276.77 sq ft (25.713 m2)
Racing
PHRF234

The Amphibi-Con 25, often just called the Amphibi-Con, is an American trailerable sailboat that was designed by E. Farnham Butler and Cyrus Hamlin as a racer-cruiser and first built in 1954. The design was one of the first "trailer sailers" and helped popularize this class of boat.[1][2][3][4]

Production

The design was built by Butler's Mount Desert Yachts, Sailstar Boat Company and Burr Brothers Boats in the United States , starting in 1954. Some were also built in Finland . A total of 125 boats were completed, but it is now out of production.[1][4][5][6]

Design

The Amphibi-Con 25 is a recreational keelboat, initially built predominantly of glued wooden strip construction. In 1964 the Sailstar Boat Company constructed a mold and built some from fiberglass, with wood trim and these were sold as kits, semi-finished or ready-to-sail.[1][4]

The boat has a fractional sloop rig, with a masthead sloop rig optional. The hull has a raked stem, a plumb transom, reverse sheer, a keel-mounted rudder controlled by a tiller and a fixed long keel with a cutaway forefoot, plus a retractable centerboard. The wooden version displaces 3,500 lb (1,588 kg) and carries 1,100 lb (499 kg) of lead ballast, while the fiberglass version displaces 4,000 lb (1,814 kg).[1][4]

The boat has a draft of 4.25 ft (1.30 m) with the centerboard extended and 2.33 ft (0.71 m) with it retracted, allowing ground transportation on a trailer.[1][4]

The boat is normally fitted with a small 6 to 10 hp (4 to 7 kW) outboard motor mounted in an aft lazarette well, for docking and maneuvering. The fuel tank is a portable type, while the fresh water tank has a capacity of 20 U.S. gallons (76 L; 17 imp gal).[1][4]

The design includes a canvas-covered cabin that allows sunshine and fresh air in fine weather or covering in inclement weather. The boat has sleeping accommodation for four people, with a double "V"-berth in the bow cabin and two straight settees in the main cabin. The galley is located on both sides, just aft of the forward cabin. The galley is equipped with a two-burner stove on the starboard side and a sink and icebox on the port side. The head is located just aft of the bow cabin on the port side. Cabin headroom is 68 in (170 cm).[1][4]

For sailing the design is equipped with a topping lift that runs from a V-shaped boomkin and may also be fitted with a spinnaker for downwind sailing.[4]

The design has a PHRF racing average handicap of 234 and a hull speed of 6.2 kn (11.5 km/h).[4]

Operational history

The boat is supported by an active class club that organizes racing events, the Amphibi-con Association.[7]

In a 2010 review Steve Henkel wrote, "among her comp[etitor]s, the A/C 25 is the lightest boat with the least ballast and close to the highest SA/D ratio, indicating that she will be among the liveliest in light air, but with her relatively low Motion Index, will tend to be jumpy in a seaway. We recall spending some time on one of these boats with another couple, and we found it to be comfortable, light, and airy."[4]

See also

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 McArthur, Bruce (2020). "Amphibi-Con sailboat". sailboatdata.com. https://sailboatdata.com/sailboat/amphibi-con. 
  2. McArthur, Bruce (2020). "E. Farnham Butler". sailboatdata.com. https://sailboatdata.com/designer/butler-e-farnham. 
  3. McArthur, Bruce (2020). "Cyrus Hamlin". sailboatdata.com. https://sailboatdata.com/designer/hamlin-cyrus. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 Henkel, Steve: The Sailor's Book of Small Cruising Sailboats, page 321. International Marine/McGraw-Hill, 2010. ISBN:978-0-07-163652-0
  5. McArthur, Bruce (2020). "Mount Desert Yacht Yard". sailboatdata.com. https://sailboatdata.com/builder/mount-desert-yacht-yard. 
  6. McArthur, Bruce (2020). "Sailstar Boat Co. (USA) 1960-1971". sailboatdata.com. https://sailboatdata.com/builder/sailstar-boat-co-usa. 
  7. McArthur, Bruce (2020). "Amphibi-Con (Mount Desert Yachts, Controversy)". sailboatdata.com. https://sailboatdata.com/association/amphibi-con-mount-desert-yachts-controversy.