Design and Construction
Northshore Yachts built the 420 in fiberglass, with a solid hull and deck. The boat displaces 26,014 pounds, including 7,782 pounds of iron ballast, and has a beam of 13.22 feet. It measures 42.19 feet overall, with a 36.45-foot waterline.
Variable draft has long been a defining feature of the Southerly range. On the 420, a highly developed swing keel pivots down to give the hull a wing-keel profile. Raised, it provides a protected 2-foot-7-inch shoal mode.
The twin rudders complement the swing keel, keeping the helm authoritative when the boat is heeled or dried out. Overall, the 420 continues the established collaboration between Rob Humphreys and Northshore Design rather than marking a break from it.
Rig and Handling
The fractional sloop rig carries 785 square feet of sail area, giving a sail-area-to-displacement ratio of 14.3 and a hull speed near 8 knots.
Cruising World was unambiguous about the keel-down configuration: the 8-foot-9-inch draft guarantees weatherly bluewater performance. The deep blade suppresses leeway and gives the boat the posture of a fixed-keel offshore cruiser.
With the keel raised, the same hull draws barely more than two and a half feet. That allows a couple to explore shallow estuaries and dry out in places most 42-footers can’t reach. Push-button operation also removes the physical labor demanded by older lifting-keel systems.
Accommodations
The 420 has an inviting deck-saloon interior. Opening ports across the forward face of the deckhouse bring light and views into the main living space.
The center-cockpit arrangement places the helm under the trunk cabin, while the forward-facing ports give the saloon a panoramic character unusual in a boat with a keel trunk running through the accommodation. The Humphreys and Northshore layout feels like a protected, light-filled cruising home rather than a stripped-out passage-maker.
Verdict
The Southerly 420 is a thoughtful execution of the variable-draft concept: a genuine bluewater hull that can also sit upright in a drying harbor. Its deck saloon and forward opening ports are real cruising assets, while the push-button keel makes the shoal-draft capability practical for a short-handed crew.
The trade-offs are the central keel trunk running through the saloon and the maintenance requirements of the wing-keel system—responsibilities any swing-keel owner must respect.
Pros
- Deep 8-foot-9-inch draft with the keel down for weatherly offshore performance
- Shoal 2-foot-7-inch draft with the keel raised, suitable for estuaries and drying moorings
- Light-filled deck saloon with forward opening ports
- Button-operated swing keel reduces crew effort
Cons
- Keel trunk bisects the accommodation volume
- Swing-keel hinge and seal demand disciplined ownership
