Operating an aircraft with improved aileron and landing function

Abstract

An aircraft having two separate landing flaps on each wing which are actuated together in a landing mode or function, and wherein the outer flap of each wing is also separately actuated in an aileron mode or function separate from the inner flap.

Claims

1. An aircraft having two wings (10), a pair of inner and outer landing flaps (30, 40) arranged on each wing (10) of the aircraft, a first drive unit (100) arranged to lower both said flaps (30, 40) of both pairs in a landing mode, actuators (20) arranged for moving both said flaps (30, 40) of both pairs in response to said first drive unit (100), transmissions arranged to be driven by said first drive unit (100) and to drive the actuators (20), active differential gear boxes (200) on each wing (10) through which the transmissions run from the inner flaps (30) to the outer flaps (40) and dividing the transmissions between the flaps (30, 40), with inner transmission sections arranged for activating the inner flaps (30) and outer transmission sections arranged for activating the outer flaps (40), second drive units arranged to adjust the outer flaps (40) individually or differentially with respect to one another during a cruising flight mode to provide roll or aileron functionality while the inner flaps (30) remain stationary, said second drive units acting only on the outer sections of the transmissions through the active differential gear boxes (200) and arranged in the respective aircraft wings (10) or fuselage of the aircraft, and only said two flaps (30, 40) are positioned on each wing (10) which is devoid of a separate aileron flap.

2. The aircraft of claim 1, wherein said respective active differential gear boxes (200) are configured to decouple said outer flaps (40) from said respective inner flaps (30) and first drive unit (100) during cruising.

3. A method of operating an aircraft having two wings (10) and a pair of inner and outer landing flaps (30, 40) arranged on each wing (10) of the aircraft, comprising positioning active differential gear boxes (200) along transmissions between the inner and outer flaps (30, 40) of each pair to divide the transmission between the flaps (30, 40), with inner transmission sections activating the inner flaps (30) of each pair and outer transmission sections activating the outer flaps (40) of each pair, lowering both said flaps (30, 40) in both pairs in a landing mode from a first drive unit (100) coupled to both said flaps (30, 40) in both pairs through transmission drives by the first drive unit (100) and driving actuators (20) positioned at said respective flaps (30, 40), activating the outer flaps (40) of each pair in aileron mode individually or differentially with respect to one another during a cruising mode to provide roll or aileron functionality while the inner flaps (30) of each pair remain stationary, by second drive units acting only on the outer transmission sections through the differential gear boxes (200) and being arranged in the respective aircraft wings (10) or fuselage of the aircraft, and omitting a separate aileron flap from each wing (10), so that turning the aircraft during cruising is only effected by activating the outer flaps (40) of each wing (10).

4. The method of claim 3, comprising decoupling said first drive unit (100) and respective inner flaps (30) from said outer flaps (40) during cruising.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further details and advantages of the invention will be explained in more detail with reference to an embodiment shown in the drawing. There are shown:

(2) FIG. 1: a schematic view of a wing with only one landing flap and with one flap which is used as aileron and as landing flap;

(3) FIG. 2: a schematic view of arrangements of landing flaps and ailerons in a wing known from the prior art; and

(4) FIG. 3: a schematic view similar to FIG. 1 and showing two wings each having only one landing flap and one flap which is used as aileron and as landing flap; and

(5) FIG. 4: a flow chart of the method according to the present invention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

(6) FIG. 1 shows a wing 10 of an aircraft comprising one landing flap 30 (inboard) and one flap 40 (outboard) which may be useddepending on the flight modeas landing flap or as aileron.

(7) Reference numeral 100 is the first drive unit according to the present invention and is a power control unit PCU which may be located in the fuselage of the aircraft. The PCU is controlled by a first control unit (not shown). It is activated in the landing mode of the aircraft. In this case both flaps 30, 40 are used as landing flaps.

(8) The movement of the flaps 30, 40 is performed by means of actuators 20 which are driven by a transmission which is driven by the PCU 100. As shown in FIG. 1 the transmission runs through the active differential gear box 200.

(9) In case of cruise flight, the landing flap 30 remains stationary. The flap 40 in that case is used as aileron. In the aileron mode the flap 40 is driven by the second drive unit 200 which an active differential gear box and not by the PCU 100. The control of the operation of the second drive unit is performed by means of a second control unit (not shown). The transmission power of the active differential gear box 200 is transmitted to the actuators 20 of the flap 40 (and not to the actuators 20 of the landing flap 30) in order to perform the aileron function.

(10) An improvement in the weight and cost balance is achieved by the present invention as well as of the safety of the high-lift system of an aircraft. The second drive unit can be arranged in the aircraft wing or also at a central site in the fuselage of the aircraft.

(11) The second drive unit can comprise an electrical or hydraulic drive for the partial or complete taking over of the aileron function. This in particular applies during cruise flight.

(12) Where possible, it is conceivable in particular to use the outer landing flap as the aileron which is actuated by the second drive unit in the wing (high-lift function). The inwardly offset or inner landing flap can be stationary in this respect.

(13) This configuration allows the saving of redundancies/actuators at the aileron by using already present drive units in the wing for taking over the partial or complete aileron function. As stated, in systems with a plurality of ailerons, one aileron can possibly be completely saved.

(14) A weight reduction results due to the association of the high-lift function with the aileron function and thus the possible partial or complete saving of redundancies/actuators at the aileron.

(15) The arrangements in accordance with the invention shown in FIG. 1 are preferably present in both wings. The arrangement is preferably mirror symmetrical.

(16) FIG. 3 shows two wings in which the first drive unit 100 is shared by the flap systems of both wings for synchronized movement, i.e., in landing mode. Furthermore, in aileron mode, the outer flaps 40 are individually moved by the respective second drive units coupled thereto through the respective differential gear boxes 200 as shown. The same control surface 40 functioning as a landing flap during landing also carries out aileron function during cruising or flight. This is achieved by connecting the control surface or flap 40 through the respective differential gear box 200 to an additional actuator or drive unit (as shown in FIG. 3) that is independent from the main actuator or first drive unit 100, and decoupling the outer flaps 40 from the first drive unit 100 (and inner flaps 30) during cruising.

(17) Upon activation for landing mode, the first drive unit 100 and respective inner flaps 30 are coupled to the outer flaps 40 through the respective differential gear boxes 200 which also de-couple the respective second drive units on each wing from the outer flaps 40. Each outer flap 40 is mounted upon the respective wing to be rotatable either upwardly or downwardly through the respective second drive units, so the aircraft can turn upon cruising by raising one of the outer flaps 40 and lowering the other of the outer flaps 40.