When Kirby introduced his Laser at the New York Boat Show in 1970 there was a groundswell of interest -- and more than 100 orders. But without the means to manufacture the Laser in volume, Kirby licensed the rights to established builders in three separate geographic regions -- Europe, North America, and rest of world. Although he imposed "one design" restrictions along with the licenses, Laser variations proliferated, mainly in Europe. In contrast, the Force 5 was designed and produced by AMF, who dominated the bowling equipment market after World War II. Over a couple of decades of growth, AMF diversified by acquiring a raft of recreational product companies like Harley-Davidson motorcycles, Head skis, and Ben Hogan golf clubs. In 1969 AMF acquired the Alcort sailboat company, which had been founded in 1947 by Al Bryan and Cort Heyniger to produce the original Sailfish sailboard, and which introduced their blockbuster fiberglass Sunfish dinghy in 1960. Under AMF, the Alcort subsidiary produced a series of recreational sailboats. Some were hits -- the Apollo sloop (also designed by Kirby), Minifish (a smaller, cheaper version of the Sunfish), Puffer (from Scott), Sunbird (Scott and Evans), and the Zuma. Other AMF designs became historical footnotes -- the Hilu (a proa), the Tiga (windsurfer), and the Trac catamaran.
AMF, like many other companies that had gone on acquisition sprees during the 1960s and 70s, began to break up and sell off their subsidiaries during the high-inflation 1980s. According to the Sunfish class history, AMF's small boats were spun off into a reconstituted "Alcort Inc" in 1986. And two years later in 1988, Pearson Yachts, which itself had been split off from the Grumman conglomerate (still famous for their aluminum canoes and rowboats), bought Alcort -- and O'Day and Cal Boats (aka, Jensen Marine). Separately Pearson also acquired the rights to produce the Laser from Vanguard, the original manufacturer licensed in North America. But in 1991, rocked by an economic recession and the impact of a 10% luxury tax on boat purchases, Pearson declared bankruptcy. SunfishLaser Inc ("SLI") was then created (under Peter Johnstone, son of Bob Johnstone, the founder of J Boats, and with significant funding from North Sails -- the authorized Laser sail supplier) to produce AMF's best selling products, the Sunfish, the Laser, and the Zuma.
Since the Laser and the Force 5 were so similar in size and performance, SLI in effect killed the Force 5 in order to focus all commercial and racing attention on the Laser, which, based on its Portsmouth ratings, is the faster of the two. The Laser also became an Olympic class boat in 1996, and more than 200,000 boats have now been built. SLI sold the Force 5 design rights to Weeks Boat Yard (in 1994) who continued to produce boats that improved upon the AMF design. Altogether, maybe 15,000 Force 5's have been built, a stark contrast to the order of magnitude greater number of Lasers produced since it's introduction in 1971. But it turns out that Alcort's first racing dinghy -- the Sunfish -- is still the production champ; more than 300,000 Sunfish were built as of 2001, it's 50th anniversary. This year, 2021, is the Laser's 50th anniversary; and with current worldwide production at less than 2,000 boats a year, there's little chance that the Laser will ever surpass the Sunfish as the production king of racing dinghies.
Here are some comparative specifications for the Force 5 and the Laser, as compared to the Sunfish...from SailboatData.com
Sunfish
Length, overall, 13'-9"
Length, waterline, 13 feet
Beam, 4'-1"
Weight, 120 pounds
Sail area, 75 square feet
D-PN Rating, 99.6
Displacement/Length ratio (prismatic shape): 26.2
SA/Displacement ratio (power to weight): 47.0
Brewer comfort ratio: 2.31
Capsize screening ratio: 3.23
Force 5
Length, overall, 13'-10"
Length, waterline, 13'-2"
Beam, 4'-10"
Weight, 145 pounds
Sail Area, 91 square feet
D-PN Rating, 95.4 (lower is faster)
Displacement/length ratio: 27.3 (lower is better)
SA/Displacement ratio: 54.0 (higher is better)
Comfort ratio: 1.98 (higher is more comfortable; racing boats are less than 20)
Capsize screening ratio: 3.72 (higher is more stable)
Laser
Length, overall, 13'-9"
Length, waterline, 12'-6"
Beam, 4'-7"
Weight, 130 pounds
Sail Area, 76 square feet
D-PN Rating, 91.1
Displacement/Length ratio (prismatic shape): 26.4 (better than Force 5)
SA/Displacement ratio: 47.4 (lower "power/weight" than Force 5)
Brewer comfort ratio: 2.01 (about the same as Force 5)
Capsize screening ratio: 3.60 (less stable than Force 5)
All of these dinghies have unstayed aluminum masts. As mentioned above, the Sunfish has a lateen rig. The mast is 2-1/4 inches in diameter and is only 10 feet long, while the gaff and boom spars, 1-1/2 inches in diameter, are both 14 feet long -- a big disadvantage when transporting the boat. The Force 5 and the Laser were both designed as sloop-rigged cats with sleeved sails. The Laser mast is 20'-2" in length. The Force 5 mast is 21 feet long. Both the Force 5 and the Laser have multi-part aluminum masts. The Laser is in two parts; the base is 9'-5" and the top section is 10'-11" long. The Force 5 mast comes in three parts, and the longest section is 9'-10" long. The base section for both masts is 2-1/2 inches in diameter, so a Laser rig will fit into a Force 5 mast step, and vice versa. I have found, through experience, that it's important to have the boat on the ground before you try to step the mast (with sail) on either the Laser or the Force 5. The boom for both rigs is 9 feet long; the outhaul on the Force 5 is internal, whereas the Laser uses lower-cost external lines and blocks. Since all the spar components are shorter than the boats, it is much easier to transport a Force 5 or a Laser than a Sunfish.
The sail dimensions, from the Sailrite (www.sailrite.com) database, are as follows. For the Laser: luff = 16.5 feet; foot = 9 feet; leech = 18.32 feet. For the Force 5: luff = 17.75 feet; foot = 8.62 feet; leech = 19.27 feet. As mentioned above, the Force 5 sail has 20% more area (15 SF) more area than the Laser (76 SF).
The mast "bury" on both the Laser and the Force 5 is 14 inches. On the Force 5 the boom height above the deck is 19 inches. The boom height on the Laser and the boom height of a Laser rig on a Force 5 hull (the latter verified by actual measurement) is about 23 inches, or 4 inches higher than the Force 5 boom.
The original Force 5 from AMF was built with four clam cleats on the foredeck to handle the cunningham and downhaul lines. The Laser has deck-mounted cam cleats that are typically used during racing for the downhaul and the outhaul (no cunningham). Both boats have their sheet rachet blocks located mid-boat, just aft of the daggerboard trunk. The Force 5 has a traveler attached to a thwart across the cockpit. The original Force 5 is set up for boom-end sheeting with a fixed traveler line across the aft deck, while later versions have two blocks in the middle of the boom for the sheet directly above a multipart rachet block. The Laser uses boom-end sheeting and has a simple tensioning adjuster for the traveler line (an advancement over the simple fixed traveler used on the Sunfish).
The foils on AMF's Force 5 are constructed of solid mahagony. Based on the class rules, the daggerboard's maximum chord is at 36% of it's width (3-3/4 inches of the 11.75 to 12 inches width limit). The rudder surfaces are flat and parallel except it can be profiled within 1-1/4 inches of the trailing edge. The Laser foils are composite construction. The class rules do not specify the foil cross-section, but a measured daggerboard's maximum chord is at 1/3 of it's width (11 cm over 33 cm, or 13 inches, in width). The shape of the Laser's daggerboard and its rudder is much more streamlined NACA profiles (probably NACA 0010 and 0012). Both boats have kick-up rudders; the Force 5 rudder is "spring-loaded" and does not work very well, so it does not need a downhaul. The Laser's rudder blade does have a downhaul line.
One of the biggest design differences between the two hull designs is that, due to its large footwell, the Force 5 can comfortably accommodate a crew of two even though it was designed for single-handed sailing, whereas the Laser cannot. I suspect that the Force 5 is more comfortable to sail even if you are sailing it single-handed. Lasers "wear out" when the deck becomes "spongy" -- especially prevalent on Lasers sailed by heavier skippers. The Force 5 is designed and built, by comparison, much stiffer than the Laser and should not have that particular issue. Look for holes and flex in the bottom rather than soft decks.
Because the Laser is still being built and it remains a popular teaching boat, as well as an Olympic class boat, it's easy to find literally any part, and new "class legal" sails are readily available. You can also find "practice" sails for just a few hundred dollars (www.intensitysails.com). But if you need rare parts such as a mast or boom for a Force 5, your best bet might be to find another Force 5 and cannibalize it (older boats sell for under $500). You can get a "zipper luff" sail ("class legal" and $635 in 2010, the date on their parts list) from Weeks Boat Yard, if they are still in business when you call. But a "practice" sail from Intensity Sails is less than $200.
References
Force 5 History, http://www.force5sailboats.com/history.htm
"The Pearson Era," https://goodoldboat.com/the-pearson-era/
Force 5 zipper-luff sail, http://www.force5sailboats.com/zipper_rig.htm
"The story of the former Olympian who designed the world's more beloved boat," Popular Science, 2019, https://www.popsci.com/bruce-kirby-laser-sailboat/
Laser Class, https://www.laserinternational.org/
