Design and Construction
The hull is solid fibreglass, laid up by hand in the heavy GRP tradition Thames Marine used across its 1960s and 1970s output, and the yard that built her is the British firm Thames Marine Ltd. The Snapdragon 21 is built by the British yard Thames Marine Ltd. Her beam is 7.25 feet against 21 feet overall, an l/b ratio of 2.90. With 2,200 lbs displacement and 950 lbs iron ballast, the 43% ballast ratio and 168 displacement-length ratio confirm the light-racer categorisation, while the 12.8 Motion Comfort Ratio suggests a brisk motion. The wetted bottom runs about 129 square feet and immersion is 455 lbs per inch.
Rig and Handling
She carries a masthead sloop rig with 188 square feet of sail, a sail-area-to-displacement ratio of 17.79. The capsize screening value is 2.23 and theoretical hull speed is 5.7 knots. Jib and genoa sheets are 21 feet of 3/8-inch line, mainsheet 52.5 feet, spinnaker sheet 46.2 feet. The bilge keels hold draft to 2.49–2.79 feet by load, so the boat can enter even shallow marinas that would ground a deeper boat.
Known Issues
Builder context notes 1960s and 1970s Snapdragon decks typically used plywood or balsa coring, which on an aged example warrants survey for delamination, but no defect is attributed to this model.
Refits and Ownership
Thames Marine ceased manufacturing in 1981, Maplin Marine briefly continued distribution, then closed. For a 1970-start boat, solid hulls survive well but original deck coring and period rigging are usual refresh items, and shoal draft makes her an easy drying-mooring candidate.
The Verdict
The Snapdragon 21 is a tidy British bilge-keeler whose light-racer numbers, shoal draft, and simple rig make her an accessible coastal sailor.
Pros
- Shoal bilge-keel draft of 2.49–2.79 ft lets her use shallow marinas and dry out level
- Light-displacement proportions with 17.79 SA/D for lively performance
- Solid fibreglass hull in heavy hand-laid Thames Marine tradition
Cons
- Narrow beam and 21-ft length limit accommodation to minimal coastal camping
- 12.8 Motion Comfort Ratio means a brisk rather than gentle motion
