Aircraft with thrust and lift augmenting airfoil

Claim 2

An aircraft having a short field takeoff and landing capability comprising: a fuselage; a main wing attached to said fuselage; a jet engine emitting substantially its entire exhaust stream at a location to flow rearwardly from above the trailing edge of said wing; an auxiliary thrust augmenting airfoil which is lower than and offset rearwardly with respect to said wing; and means mounting said thrust augmenting airfoil for adjusting movement relative to the fuselage and wing between a cruise position in which said airfoil is generally parallel to, but lower than, and spaced a substantial distance from the wing, and a takeoff position in which the airfoil is inclined at a downward and rearward angle of attack in a manner inducing downward and rearward movement of said exhaust stream by the Coanda Effect, with said airfoil in said takeoff position having its leading edge spaced rearwardly and downwardly from the trailing edge of the wing to define with said trailing edge a gap across which said exhaust stream flows in a relation drawing air through the gap from under the wing to attain thrust augmentation.

Claim 3

An aircraft as recited in claim 1, in which said means mount the thrust augmenting airfoil for essentially pivotal movement about an axis which extends generally transverse to the fuselage and is generally between the leading and trailing edges of the airfoil in a relation such that as the airfoil pivots from said cruise position toward said takeoff position, the leading edge of the airfoil swings upwardly nearer to the level of said wing and rearwardly with respect thereto.

Claim 4

An aircraft as recited in claim 1, in which said thrust augmenting airfoil is end-plated and mounted for pivotal movement between said positions and is located to promote Coanda Effect and implement the overall Bernoulli Effect of the entire wing/flap-thrust augmenting airfoil.

Claim 5

An aircraft as recited in claim 1, in which said jet engine has an exhaust nozzle with a height dimension "t" defining the height of said exhaust stream, and both the vertical dimension and the horizontal dimension of said gap in the takeoff position of the thrust augmenting airfoil are between about 3 and 5 times the height of said nozzle.

Claim 6

An aircraft as recited in claim 1, in which the thrust augmenting airfoil is movable to a more inclined air braking position in the final phase of landing, and has a trailing edge elevator movable to a near vertical condition in said air braking position of the airfoil.

Claim 7

An aircraft as recited in claim 1, in which said means mount said thrust augmenting airfoil for movement to a landing position in which the airfoil is inclined downwardly and rearwardly at a more abrupt angle of attack than in said takeoff position and has its leading edge spaced rearwardly and downwardly from said trailing edge of the wing with a space therebetween.

Claim 8

An aircraft as recited in claim 6, including a flap movable from a retracted position to a position of extension across said space between the trailing edge of the wing and the leading edge of said airfoil in said landing position of the latter.

Claim 9

An aircraft as recited in claim 1, in which said leading edge of said thrust augmenting airfoil is spaced rearwardly and downwardly from said trailing edge of the wing in said cruise position of the airfoil as well as in said takeoff position.

Claim 10

An aircraft as recited in claim 1, in which said airfoil in said takeoff position has its leading edge spaced lower than said trailing edge of the wing a distance substantially greater than the maximum thickness of the airfoil.

Claim 11

An aircraft as recited in claim 1, including a flap movable between a retracted position and an active landing position of extension between the trailing edge of said wing and the leading edge of said airfoil.

Claim 12

An aircraft as recited in claim 1, in which said leading edge of said thrust augmenting airfoil is spaced rearwardly and downwardly from said trailing edge of the wing in said cruise position of the airfoil as well as in said takeoff position; said means being constructed to mount said airfoil for essentially pivotal movement between said cruise and takeoff positions about an axis which is disposed generally transversely of the fuselage and is generally between the leading and trailing edges of the airfoil in a relation such that as the airfoil pivots from cruise position toward takeoff position the leading edge of the airfoil swings upwardly nearer to the level of said wing and rearwardly with respect thereto, said means mounting said airfoil for further pivotal movement beyond said takeoff position to a landing position in which it is inclined downwardly and rearwardly at a greater angle of attack than in the takeoff position and has its leading edge higher than in the takeoff position and farther rearwardly than in the takeoff position but still offset rearwardly and downwardly from the trailing edge of the wing with a space therebetween.

Claim 13

An aircraft as recited in claim 11, in which said jet engine has an exhaust nozzle with a height dimension "t" defining the height of said exhaust stream, and both the vertical dimension and the horizontal dimension of said gap in the takeoff position of the thrust augmenting airfoil are between about 3 and 5 times the height of said nozzle.

Claim 14

An aircraft as recited in claim 12, in which said airfoil has a main body portion and a trailing edge elevator movable relative to said main body portion from a position of essential alignment therewith to a position disposed at an angle to and more directly vertical than said main body portion.

Claim 15

An aircraft as recited in claim 13, including a flap movable between a retracted position and an active landing position of extension between the trailing edge of said wing and the leading edge of said airfoil.