Link Mechanisms, Including Stephenson II Link Mechanisms for Multi-Position Flaps and Associated Systems and Methods

An aircraft system comprising:

• a fuselage;
• a wing attached to the fuselage, the wing having an external flow surface, the external flow surface comprising an upper portion and a lower portion, the airfoil forming a base link;
• a six-bar linkage coupled to the airfoil and having a Stephenson II configuration, including:
• a binary second link pivotably connected to the airfoil;
• a ternary third link pivotably connected to the second link;
• a binary fourth link pivotably connected to the third link;
• a ternary fifth link pivotably connected to the airfoil and the fourth link;
• and
• a binary sixth link pivotably connected to the third link and the fifth link;
• and
• a deployable leading edge panel carried by the linkage, the leading edge panel being movable via the linkage among a stowed position, a landing position, and a take-off position, and wherein the leading edge panel (a) forms a part of the lower portion when in the stowed position, (b) has a trailing edge that is spaced apart from the upper portion to form a gap when in the landing position, and (c) at least partially seals the gap when in the take-off position, further wherein the leading edge panel maintains a generally fixed shape as it is moved among the stowed position, the landing position and the take-off position, and wherein fourth link includes a generally rigid support panel that carries the leading edge panel.

An aircraft system comprising:

• a fuselage;
• a wing attached to the fuselage, the wing having an external flow surface, the external flow surface comprising an upper portion and a lower portion, the airfoil forming a base link;
• a six-bar linkage having a Stephenson II configuration and including:
• a binary second link pivotably connected to the airfoil;
• a ternary third link pivotably connected to the second link;
• a binary fourth link pivotably connected to the third link;
• a ternary fifth link pivotably connected to the airfoil and the fourth link;
• and
• a binary sixth link pivotably connected to the third link and the fifth link;
• and
• a deployable leading edge panel carried by the linkage, the leading edge panel being movable via the linkage among a stowed position, a landing position, and a take-off position;
• a bullnose pivotably coupled to the leading edge panel;
• a support panel pivotably coupled to the leading edge panel, the bullnose, and the third link;
• and
• a seventh link pivotably connected between the support panel and the fifth link;
• wherein:
• the leading edge panel (a) forms a part of the lower portion when in the stowed position, (b) has a trailing edge that is spaced apart from the upper portion to form a gap when in the landing position, and (c) at least partially seals the gap when in the take-off position;
• and
• the leading edge panel is flexible and changes shape as the leading edge panel moves from the stowed position to at least one of the landing position and the take-off position.

A method for operating an aircraft wing system, comprising:

• deploying a leading edge panel relative to an airfoil having an external flow surface;
• shielding the airfoil with the leading edge panel during take-off to at least restrict debris from attaching to the external flow surface;
• stowing the leading edge panel after take-off;
• promoting laminar flow over an upper portion of the external flow surface during cruise;
• and
• deploying the leading edge panel to be spaced apart from a leading edge of the wing during at least one of approach and landing.