GB2373488A

GB2373488A - Launching, refuelling and recovering an aircraft

Info

Publication number: GB2373488A
Application number: GB0106989A
Authority: GB
Inventors: Richard George Harrison
Original assignee: BAE Systems PLC
Current assignee: BAE Systems PLC
Priority date: 2001-03-21
Filing date: 2001-03-21
Publication date: 2002-09-25
Also published as: GB0106989D0

Abstract

An unmanned aerial vehicle (UAV) is carried under the wing of a carrier aircraft by releasable latching devices 26, 27 and is connected to a drogue 24 at the end of a retractable refuelling hose 30 by a latching mechanism 32. For launching the UAV, the latching devices are released, and the hose is extended so that the UAV which is secured to the drogue trails behind the carrier aircraft. The latching mechanism 32 is then released to disconnect the UAV from the drogue. Recovery of the UAV is effected by reversing the above steps, and in flight refuelling can be accomplished in the usual way. The UAV is provided with sufficient power to maintain its stability when trailing the carrier aircraft prior to disconnection from the drogue.

Description

Airborne Launch of an Aircraft from a Larger Carrier Aircraft The invention relates to airborne launching of an aircraft from a larger carrier aircraft. In particular but not exclusively, the invention is concerned with the launching, refuelling and recovering of an unmanned aerial vehicle (UAV).

At present, the majority of UAVs are ground launched and require fuel to get to and from their location. The present invention is concerned with the airborne launch of a UAV or other aircraft from a larger carrier aircraft.

According to one aspect of the invention there is provided a method of launching an aircraft comprising releasably connecting the aircraft to a larger carrier aircraft and to an extendable refuelling device on the carrier aircraft whereby with the carrier aircraft airborne, the aircraft is launched by disconnecting the aircraft from the carrier aircraft, extending the refuelling device to enable the aircraft to trail behind the carrier aircraft, and disconnecting the trailing aircraft from the refuelling device.

Such a method is particularly advantageous as it uses an existing refuelling device on the carrier aircraft to assist in the launch of a smaller aircraft.

In a preferred embodiment, the aircraft can be refuelled in flight following launch by connecting the aircraft to the extended refuelling device on the carrier aircraft. Fuel on the carrier aircraft is then passed through the refuelling device to the aircraft. In that respect, the refuelling device can serve to re-fuel the aircraft as well as to facilitate launch.

The method may include recovering the aircraft in flight by reconnecting the aircraft to the refuelling device, retracting the refuelling device with the aircraft connected thereto and reconnecting the aircraft to the carrier aircraft.

According to a second aspect of the invention, there is provided a method of launching, refuelling and recovering an aircraft comprising releasably connecting the aircraft to a larger carrier aircraft and to an extendable refuelling device on the carrier aircraft, launching the aircraft from the carrier aircraft when airborne by disconnecting the aircraft from the carrier aircraft, extending the refuelling device to enable the aircraft to trail behind the carrier aircraft, and disconnecting the trailing aircraft from the refuelling device, refuelling the aircraft in flight after launch by connecting the aircraft to the extended refuelling device on the carrier aircraft and passing fuel from the carrier aircraft through the refuelling device to the aircraft and recovering the aircraft by connecting the aircraft in flight to the refuelling device, retracting the refuelling device with the aircraft connected thereto and reconnecting the aircraft to the carrier aircraft.

It will be appreciated that the airborne launching, refuelling and recovering of the aircraft is advantageous in a number of respects but, in particular, should simplify the construction of the aircraft in that the aircraft does not require any take-off and landing systems which are essential where the aircraft is launched from and subsequently lands on the ground.

In either aspect: The method preferably comprises releasably connecting the aircraft to the carrier aircraft beneath the wing of the carrier aircraft.

The method further comprises using a refuelling device in the form of a hose which is extendable and retractable on the carrier aircraft and providing on the hose means, such as a drogue, by which the aircraft can be connected to the hose for refuelling.

The method may include providing the aircraft with sufficient power to maintain stability of the aircraft when trailing the carrier aircraft connected to the refuelling device.

A method in accordance with the invention will now be described by way of example with reference to the accompanying drawings in which : Figure 1 is a side view of a typical UAV ; Figure 2 is a side view of part of the larger carrier aircraft showing a pod arranged beneath a wing and an associated refuelling drogue; Figure 3 shows the UAV of Figure 1 releasably connected to the carrier aircraft and having a nose section located in the drogue; Figure 4 shows part of the UAV and drogue and part of a refuelling hose and; Figure 5 shows the hose extended from the pod of the carrier aircraft with the UAV located In the drogue ready for launch.

The UAV of Figure 1 is of generally known kind and it is pointed out that the present invention is not limited to the launch, refuelling or recovery of a UAV of that specific form. UAV, indicated generally at 10, has a fuselage 12 having nose section 14.

Looking at Figure 2, a carrier aircraft 16 has a fuselage 18 and wings 20, only one of which is shown in Figure 2. The lower side of the wing 20 carries a pod 22 containing a hose drum (not shown) having a free-end connected to a drogue 24. For full details of the construction of the pod, reference should be made to our co-pending patent application entitled A system for Airborne Launch of an Aircraft from a Larger Garner Aircraft, reference number XA1482 filed simultaneously herewith. The pod 22 in the present example constitutes the aforesaid holder although the term"holder"is not limited to a pod-like construction.

As shown in Figure 3, the UAV 10 can be mounted beneath the wing 20 with its nose section 14 positioned within the drogue 24 and with its fuselage 12 releasably connected to the wing 20 by means of a latching device 26 on the wing 20 and a further latching device 27 on the pod 22.

As shown in Figure 4, the leading end of the nose 14 or a probe (not shown) on the nose 14 locates sealingly in a nozzel 28 of the drogue to enable the UAV 10 to receive fuel from the carrier aircraft 16 via a refuelling hose 30. The nose section 14 of the UAV 10 IS held securely In the drogue by a latching device on the drogue generally Indicated at 32.

To launch the UAV 10 the latching devices 26,27 are released and the hose 30 is extending from the pod 22 so that the drogue 24 and the UAV 10 trail behind the carrier aircraft 16 (as shown in Figure 5). The UAV 10 provides sufficient power from its engine (s) so that it will remain in a stable position when trailing behind the carrier aircraft 16. Once in the Figure 5 position, the latching mechanism 32 is released so as to launch the UAV 10 which then commences its mission instructions.

On completion of its mission instructions, the UAV 10 can either return to the carrier aircraft 16 for refuelling or for recovery and stowage. If the UAV 10 requires refuelling, it will dock In the extended drogue 24 as shown in Figure 5 and fuel will be transferred from the the carrier aircraft 16 through the hose 30 to the UAV 10. The UAV 10 can then detach and commence further mission instructions. If the UAV 10 is to be returned to a stowed position on the carrier aircraft 16, UAV 10 docks and latches by means of latch 32 in the drogue 24 as shown in Figure 5 and the hose 30 is retracted so as to draw the UAV 10 towards the pod 22. The UAV 10 again provides sufficient power during the operation to remain in a stable position. Once the Figure 3 position has been reached the latching devices 26 and 27 are reconnected to the UAV 10 so as to hold the UAV securely in place beneath the wing 20.

A suitable drogue 24 for use in the present invention is described in our UK Patent Application entitled A Drogue for In-Flight Refuelling reference XA1476 filed simultaneously herewith and the reader is directed to that patent application for details.

As the UAV 10 is both launched and recovered when the carrier aircraft is airborne, the UAV does not require an undercarriage and associated take-off and landing systems.

Claims

Claims A method of launching an aircraft comprising releasably connecting the aircraft to a larger aircraft and to an extendable refuelling device on the carrier aircraft whereby with the carrier aircraft airborne, the aircraft is launched by disconnecting the aircraft from the carrier aircraft, extending the refuelling device to enable the aircraft to trail behind the carrier aircraft, and disconnecting the trailing aircraft from the refuelling device.
2. A method according to claim 1 in which, following launch, the aircraft can be refuelled in flight by connecting the aircraft to the extended refuelling device on the carrier aircraft and passing fuel on the carrier aircraft through the refuelling device to the connected aircraft.
3. A method according to claim 1 in which, following launch, the aircraft can recovered in flight by reconnecting the aircraft to the refuelling device, retracting the refuelling device with the aircraft connected thereto and reconnecting the aircraft to the carrier aircraft.
4 A method of launching, refuelling and recovering an aircraft comprising releasably connecting the aircraft to a carrier aircraft and to an extendable refuelling device on the carrier aircraft, launching the aircraft from the carrier aircraft when airborne by disconnecting the aircraft from the carrier aircraft, extending the refuelling device to enable the aircraft to trail behind the carrier aircraft, and disconnecting the trailing aircraft from the refuelling device, refuelling the aircraft in flight after launch by connecting the aircraft to the extended refuelling device on the carrier aircraft and passing fuel from the carrier aircraft through the refuelling device to the aircraft and recovering the aircraft by connecting the aircraft in flight to the refuelling device, retracting the refuelling device with the aircraft connected thereto and reconnecting the aircraft to the carrier aircraft.
5. A method according to claim any of claims 1 to 4 comprising releasably connecting the aircraft to the carrier aircraft beneath a wing of the carrier aircraft.
6. A method according to any preceding claim comprising using a refuelling device in the form of a hose which is extendable and retractable on the carner aircraft and providing on the hose means by which the aircraft can be connected to the hose for refuelling.
7. A method according to any preceding claim comprising providing the aircraft with sufficient power to maintain stability of the aircraft when trailing the carrier aircraft connected to the refuelling device.
8. A method of launching, recovering and/or refuelling an aircraft substantially as described herein with reference to the accompanying drawings.