Slotted aircraft wing
AssigneeThe Boeing Company
InventorsJohn C. Vassberg, Lie-Mine Gea, James D. McLean, David P. Witkowski, Steven E. Krist, Richard L. Campbell
Life of this patent
Estimating the term…
Abstract
An aircraft wing includes a leading airfoil element and a trailing airfoil element. At least one slot is defined by the wing during at least one transonic condition of the wing. The slot may either extend spanwise along only a portion of the wingspan, or it may extend spanwise along the entire wingspan. In either case, the slot allows a portion of the air flowing along the lower surface of the leading airfoil element to split and flow over the upper surface of the trailing airfoil element so as to achieve a performance improvement in the transonic condition.
Claims77
A swept, slotted three-dimensional airfoil having a span and a predetermined three-dimensional shape tailored to improve transonic performance over an un-slotted airfoil, the airfoil comprising:
- at least one leading airfoil element having an upper surface and a lower surface;
- at least one trailing airfoil element defining a spanwise transonic cruise slot with the leading airfoil element, the trailing airfoil element having an upper surface and a lower surface, the cruise slot being positioned along the span at a position where the airfoil experiences Mach critical flow and having a predetermined three-dimensional shape to allow a portion of the air flowing along the lower surface of the leading airfoil element to diverge during a cruise condition to flow over the upper surface of the trailing airfoil element and, thereby, to provide the performance improvement.
A partial-span slotted three-dimensional airfoil having a span and a predetermined three-dimensional shape tailored to improve transonic performance over an un-slotted airfoil, the airfoil comprising:
- at least one leading airfoil element having an upper surface and a lower surface;
- at least one trailing airfoil element defining a partial-span transonic cruise slot with the leading airfoil element, the trailing airfoil element having an upper surface and a lower surface, the cruise slot being positioned spanwise along the span at a position where the airfoil experiences Mach critical flow and having a predetermined three-dimensional shape to allow a portion of the air flowing along the lower surface of the leading airfoil element to diverge during a cruise condition to flow over the upper surface of the trailing airfoil element and, thereby, to provide the performance improvement.
A method for flying a slotted aircraft wing having a predetermined three-dimensional shape tailored to improve transonic performance over an un-slotted wing, a span, at least one leading airfoil element, and at least one trailing airfoil element defining at least one spanwise transonic cruise slot with the leading airfoil element, the cruise slot being positioned along the span at a position where the wing experiences Mach critical flow and having a predetermined three-dimensional shape to allow a portion of the air flowing along a lower surface of the leading airfoil element to diverge to flow over the upper surface of the trailing airfoil element and, thereby, to provide the performance improvement, the method comprising trimming the cruise slot during a transonic condition so as to achieve a performance improvement in the transonic condition.
The method of claim 60, wherein the cruise slot comprises a plurality of partial-span slots longitudinally arranged along the wing, and wherein the method further comprises independently trimming each said slot during the transonic condition so as to achieve a performance improvement in the transonic condition.
A method for flying a swept slotted aircraft wing defining at least one spanwise transonic cruise slot positioned along the span at a position where the wing experiences Mach critical flow and having a predetermined three-dimensional shape tailored to improve transonic performance over an un-slotted wing, the method comprising using the cruise slot to divert a portion of the air flowing along a lower surface of the wing to flow over an upper surface of the wing during at least one transonic condition of the wing, the diverting at least delaying airflow separation that would occur to add drag at the transonic condition so as to achieve a performance improvement in the transonic condition.
The method of claim 70, wherein the cruise slot comprises a plurality of partial-span slots longitudinally arranged along the wing, and wherein the method further comprises independently trimming each said slot during cruise so as to achieve a performance improvement during cruise.
A method for flying a slotted aircraft wing having a predetermined three-dimensional shape tailored to improve transonic performance over an un-slotted wing, a span, a main wing portion, and a flap assembly defining at least one spanwise transonic cruise slot with the main wing portion during cruise, the cruise slot being positioned along the span at a position where the wing experiences Mach critical flow and having a predetermined three-dimensional shape to allow a portion of the air flowing along a lower surface of the leading airfoil element to diverge to flow over the upper surface of the trailing airfoil element and, thereby, to provide the performance improvement, the method comprising actuating the flap assembly during cruise to trim the flap assembly so as to achieve a performance improvement during cruise.
A method comprising tailoring a swept wing's three-dimensional geometry using three-dimensional wing pressure distribution data including information related to three-dimensional shock location such that the wing defines at least one spanwise transonic cruise slot that allows a portion of the air flowing along a lower surface of the wing to diverge to flow over an upper surface of the wing during at least one transonic condition of the wing so as to achieve a performance improvement in the transonic condition.
Dependencies are inferred from the claim text.