Strake

A strake is part of the shell of the hull of a boat or ship which, in conjunction with the other strakes, keeps the sea out and the vessel afloat. It is a strip of planking in a wooden vessel or of plating in a metal one, running longitudinally along the vessel's side, bottom or the turn of the bilge, usually from one end of the vessel to the other. On a longboat, one strake will typically be made up of numerous planks running end to end.

Special strakes

The strake immediately adjacent to the keel is known as the garboard strake. There are two, one on each side of the keel.

The uppermost continuous strake along the topsides is called the sheer strake. In old vessels, a rubbing strake was built in just below a carvel sheer strake. It was much less broad but thicker than other strakes so that it projected and took any rubbing against piers or other boats when the boat was in use. In clinker boats, the rubbing strake was applied to the outside of the sheer strake. The strakes adjacent to the garboard are referred to accordingly as the first broad and second broad. Each strake thereafter has its own special name such as bottom strakes, lowers, bilge strakes, topside strakes, and uppers. Many current pleasure craft reflect this history by providing the boat with a mechanically attached (and therefore replaceable) rub rail at the location formerly occupied by a rubbing strake, often doubling to cover the joint between a GRP hull and its innerliner.

Strake (aeronautics)

In aviation, a strake is an aerodynamic surface generally mounted on the fuselage of an aircraft to improve the flight characteristics either by controlling the airflow (acting as large vortex generators) or by simple stabilising effect.

In general a strake is longer than it is wide, in contrast to a winglet or a moustache.

Leading edge root extensions (LERX) are also sometimes referred to as wing strakes.

Nose strakes

On both supersonic and subsonic types, smaller strakes are sometimes applied to the forward fuselage to control the fuselage flow at high angles of attack ; for example the Concorde SST has small nose strakes "to get a better directional stability".

Wing strakes

For wing strakes, see Leading edge root extension (LERX).

Double delta wing aircraft (Concorde, Tupolev Tu-144, Boeing 2707 SST project) featured a forward extended leading edge that may be considered as a wing strake ; it provides the same additional vortex lift at high angle of attack by leading edge suction.

Strake (disambiguation)

Strake may refer to: