Method and device for launching aerial vehicles
AssigneeQinetiq Limited
InventorChristopher Charles Kelleher
Life of this patent
Estimating the term…
Abstract
A heavier-than-air air vehicle, particularly a long endurance, solar powered, unmanned aerial vehicle (UAV) intended for “perpetual” flight within the stratosphere, is carried to its operational altitude suspended on a tether from a helium balloon. The tether is attached at or towards a tip of the UAV's wing so that it is carried in effectively a 90° banked attitude. At the desired altitude the UAV's powerplant is started and it flies on its tether in an upwardly-spiralling path relative to the balloon until a level or near level attitude is attained, when the tether is released and the UAV is permitted to assume free flight.
Claims17
A method of launching a heavier-than-air air vehicle comprising at least an aerodynamic lifting surface and thrust-producing powerplant, the method comprising:
- raising the heavier-than-air vehicle to a desired altitude by means of a lighter-than-air vehicle;
- when said desired altitude has been reached, operating said powerplant to produce thrust with the heavier-than-air vehicle suspended at a high bank angle below the lighter-than-air vehicle by means of a tether attached to said lifting surface of the heavier-than-air vehicle at a substantially outboard position thereof, causing the tethered heavier-than-air vehicle to describe an upwardly-spiralling path relative to the lighter-than-air vehicle;
- and releasing said tether to permit free flight of the heavier-than-air vehicle when the latter has reached a desired attitude;
- wherein the heavier-than-air vehicle is initially supported by a pivotable structure in a substantially level attitude;
- said structure is pivoted to place the heavier-than-air vehicle in a substantially 90° banked attitude;
- and the heavier-than-air vehicle is released from said structure while tethered to the lighter-than-air vehicle to be raised as aforesaid.
A method of launching a heavier-than-air air vehicle comprising at least an aerodynamic lifting surface and thrust-producing powerplant, the method comprising:
- raising the heavier-than-air vehicle to a desired altitude by means of a lighter-than-air vehicle;
- when said desired altitude has been reached, operating said powerplant to produce thrust with the heavier-than-air vehicle suspended at a high bank angle below the lighter-than-air vehicle by means of a tether attached to said lifting surface of the heavier-than-air vehicle at a substantially outboard position thereof, causing the tethered heavier-than-air vehicle to describe an upwardly-spiralling path relative to the lighter-than-air vehicle;
- and releasing said tether to permit free flight of the heavier-than-air vehicle when the latter has reached a desired attitude;
- wherein the heavier-than-air vehicle has pitch control means which are caused to be in a pitch down condition at the commencement of said operation of said powerplant.
A method of launching a heavier-than-air air vehicle comprising at least an aerodynamic lifting surface and thrust-producing powerplant, the method comprising:
- raising the heavier-than-air vehicle to a desired altitude by means of a lighter-than-air vehicle;
- when said desired altitude has been reached, operating said powerplant to produce thrust with the heavier-than-air vehicle suspended at a high bank angle below the lighter-than-air vehicle by means of a tether attached to said lifting surface of the heavier-than-air vehicle at a substantially outboard position thereof, causing the tethered heavier-than-air vehicle to describe an upwardly-spiralling path relative to the lighter-than-air vehicle:
- and releasing said tether to permit free flight of the heavier-than-air vehicle when the latter has reached a desired attitude;
- wherein the heavier-than-air vehicle has yaw control means which are caused to be in a condition tending to yaw the vehicle opposite to its attachment to said tether during the course of it describing said upwardly-spiralling path.
A method of launching a heavier-than-air air vehicle comprising at least an aerodynamic lifting surface and thrust-producing powerplant, the method comprising:
- raising the heavier-than-air vehicle to a desired altitude by means of a lighter-than-air vehicle;
- when said desired altitude has been reached, operating said powerplant to produce thrust with the heavier-than-air vehicle suspended at a high bank angle below the lighter-than-air vehicle by means of a tether attached to said lifting surface of the heavier-than-air vehicle at a substantially outboard position thereof, causing the tethered heavier-than-air vehicle to describe an upwardly-spiralling path relative to the lighter-than-air vehicle;
- and releasing said tether to permit free flight of the heavier-than-air vehicle when the latter has reached a desired attitude;
- wherein said tether includes a length of fusible material adjacent to its attachment to the heavier-than-air vehicle and the heavier-than-air vehicle includes heating means for melting the same to release the tether.
Dependencies are inferred from the claim text.