Methods, apparatus, systems and a vertical take-off and landing (VTOL) vehicle are provided. The VTOL vehicle includes: a fuselage having longitudinally a front section, a central section and a rear section; a first lifting surface comprising two wings respectively secured to opposite sides of the rear section of the fuselage; a second lifting surface comprising two wings respectively secured to opposite sides of the front section of the fuselage; where each wing comprises at least one engine module, each of the engine modules being pivotally coupled to the wing and each engine module being independently controlled for transitioning between a vertical mode of flight and a horizontal mode of flight.

Methods, apparatus, systems and a vertical take-off and landing (VTOL) vehicle are provided. The VTOL vehicle includes: a fuselage having longitudinally a front section, a central section and a rear section; a first lifting surface comprising two wings respectively secured to opposite sides of the rear section of the fuselage; a second lifting surface comprising two wings respectively secured to opposite sides of the front section of the fuselage; where each wing comprises at least one engine module, each of the engine modules being pivotally coupled to the wing and each engine module being independently controlled for transitioning between a vertical mode of flight and a horizontal mode of flight.

Aircrafts having foldable wings are disclosed. An example aircraft includes a fixed wing portion, a foldable wing tip, and a hinge interface to pivotally couple the foldable wing tip and the fixed wing portion. The hinge interface has a first hinge defining a hinge axis that is substantially parallel to a fuselage centerline. The first hinge has a first dimension in a spanwise direction and a second dimension in a chordwise direction. The first dimension is greater than the second dimension.

Aircrafts having foldable wings are disclosed. An example aircraft includes a fixed wing portion, a foldable wing tip, and a hinge interface to pivotally couple the foldable wing tip and the fixed wing portion. The hinge interface has a first hinge defining a hinge axis that is substantially parallel to a fuselage centerline. The first hinge has a first dimension in a spanwise direction and a second dimension in a chordwise direction. The first dimension is greater than the second dimension.

The present invention relates to an actuator system in an aircraft for monitoring a no-back brake, which system comprises an actuator for actuating a flap of a flight control system of the aircraft, a first torque sensor for detecting a torque on the drive side of the actuator, and a second torque sensor for detecting a torque on the output side of the actuator, wherein the actuator is provided with an auto-switching no-back brake to hold the flap actuated by the actuator in position. The actuator system further has a monitoring unit, which is connected to the first torque sensor and the second torque sensor and is designed to detect an acute or imminent fault condition of the no-back brake depending on an actuator state and the detected torque values of the first torque sensor and the second torque sensor.

The present invention relates to an actuator system in an aircraft for monitoring a no-back brake, which system comprises an actuator for actuating a flap of a flight control system of the aircraft, a first torque sensor for detecting a torque on the drive side of the actuator, and a second torque sensor for detecting a torque on the output side of the actuator, wherein the actuator is provided with an auto-switching no-back brake to hold the flap actuated by the actuator in position. The actuator system further has a monitoring unit, which is connected to the first torque sensor and the second torque sensor and is designed to detect an acute or imminent fault condition of the no-back brake depending on an actuator state and the detected torque values of the first torque sensor and the second torque sensor.

An aircraft with stealth double wings comprises a main body and stealth double wings. The main body has two main wings respectively having a surface into which a space is formed. The stealth double wings respectively are located in the spaces and include a first and a second rotating shaft, a link rod, a first and a second wing. The link rod has two ends respectively connected with the two rotating shafts. The two rotating shafts respectively have another end connected with the first and second wings. Thereby, when the first wing is moved to cover and enclose the space's opening, the second wing is driven to be located within the space, and when the first wing is moved upwardly away from the space, the second wing is driven to cover and enclose the space's opening, so as to keep the surface intact.

An aircraft with stealth double wings comprises a main body and stealth double wings. The main body has two main wings respectively having a surface into which a space is formed. The stealth double wings respectively are located in the spaces and include a first and a second rotating shaft, a link rod, a first and a second wing. The link rod has two ends respectively connected with the two rotating shafts. The two rotating shafts respectively have another end connected with the first and second wings. Thereby, when the first wing is moved to cover and enclose the space's opening, the second wing is driven to be located within the space, and when the first wing is moved upwardly away from the space, the second wing is driven to cover and enclose the space's opening, so as to keep the surface intact.

A method of using a split winglet includes providing an aircraft having a winglet attach fitting attaching a split winglet to a wing. The split winglet has an upper winglet and a lower winglet. The method additionally includes maintaining the winglet attach fitting and winglet at a first height relative to a fuselage when the aircraft is non-flying, and moving the winglet attach fitting and winglet to a second height relative to the fuselage when the aircraft is flying, the second height being higher than the first height.

A method of using a split winglet includes providing an aircraft having a winglet attach fitting attaching a split winglet to a wing. The split winglet has an upper winglet and a lower winglet. The method additionally includes maintaining the winglet attach fitting and winglet at a first height relative to a fuselage when the aircraft is non-flying, and moving the winglet attach fitting and winglet to a second height relative to the fuselage when the aircraft is flying, the second height being higher than the first height.