sliding keel

Designers call it a sliding keel.

After being made a captain in 1783, he brought before the Admiralty his design for ships with a sliding keel which allowed navigation of shallow waters.

The class were fitted with a Schank sliding keel and armed with ten 18-pounder carronades and two long 24-pounders.

She had head and stern alike, two maintopsailyards, a false bottom, no hold, and sliding keels and rudders.

Bentham's designs featured little sheer, negative tumblehome, a large-breadth to length ratio with structural bulkheads, sliding keels, and were virtually double-ended.

To which is prefixed, An account of the origin of sliding keels Printed by C. Roworth for T. Egerton.

Wells & Co. of Rotherhithe built Cynthia with a shallow draught and three daggerboards (John Schank's sliding keels) for stability.

She made more leeway than a common raft between St Helen's and the Bill, for all the sharp floor and sliding keels, and she gripes like a man-trap.

Version with XP-15 wing, center of gravity adjustable sliding keel, pneumatic suspension of all three landing gear wheels and a steerable nose wheel equipped with a drum brake.

She was fitted with sliding keels (progenitors of the modern daggerboard) not long after the invention of the technology by John Schank, and she is the oldest surviving example of such a vessel.

The sliding keels, originally designed by Captain John Schank, were employed upon a number of small Royal Navy vessels around this period, although problems with leaking centerboard cases perhaps discouraged wider experimentation.

It was negligible: she had not had anything of a trial yet, no working in a heavy sea; but at least it proved that those strange sliding keels and the nameless peculiarity of her quickwork did not mean that the water poured straight in: a comfortable reflection, for he had misgivings.