Design and Construction
The Discovery 7.9 is a solid fiberglass monohull carrying 2,300 pounds of lead ballast against a 5,100-pound displacement, a 45 percent ballast ratio that places real stability in a 26-footer anchor. The beam is a modest 8.33 feet against a 21.75-foot waterline, giving a length-to-beam ratio of 3.12 and a displacement-length ratio of 221 that classifies the design among moderate racers. A fin keel and transom-hung rudder keep the underwater profile compact, and the loaded draft runs about 3.74 to 4.04 feet depending on burden, letting the boat settle into shallow marinas that deeper keelboats cannot reach. The wetted surface measures roughly 193 square feet, and the immersion rate of 631 pounds per inch tells you how little she asks of her buoyancy when crew and gear come aboard.
Rig and Handling
As a masthead sloop the Discovery 7.9 carries 318 square feet of sail, producing a sail-area-to-displacement ratio of 17.39 — enough to keep her lively without demanding a race crew. The standard running rigging is uniformly 3/8-inch line: jib and genoa sheets run 26 feet, the mainsheet 65 feet, and the spinnaker sheets 57.2 feet, dimensions that reflect a simple, serviceable deck plan rather than an over-engineered one. Her theoretical hull speed sits at 6.2 knots, the figure expected of a displacement hull this long, and the motion comfort ratio of 20.2 describes a short-bodied boat that will feel the sea more than a longer cruiser but remains within normal bounds for the size.
Seakeeping and Numbers
The capsize screening value comes in at 1.94, a figure that by the standard formula alone would admit the boat to offshore consideration for its length. That number, paired with the 45 percent ballast ratio and the fin-keel profile, sketches a small boat with a serious stability foundation rather than a pond racer. The moderate displacement and 193 square feet of wetted surface mean she is neither a featherweight nor a slug, and the 631 pounds-per-inch immersion rate confirms that her trim changes slowly under typical loads.
The Verdict
The Grampian Discovery 7.9 is a tidy, well-ballasted small sloop from the last years of a Canadian builder that knew its craft. McGruer's design is numerically coherent — a 45 percent ballast ratio, fin keel, and modest wetted surface make for a stable, handy 26-footer that can tuck into shallow harbors. The short production window means survivors are finite, but the boat itself is a sensible expression of mid-1970s cruiser-racer thinking.
Pros
- High 45 percent ballast ratio for the size, with 2,300 lb lead ballast
- Shallow-enough draft to enter marinas deeper boats cannot
- Capsize screening value of 1.94 and moderate-racer DL ratio
Cons
- Short independent production run (1975–1977) limits available hulls
- Length-to-beam of 3.12 and 20.2 comfort ratio mean a lively motion in a seaway
