Variable speed drogue

The variable speed drogue for use with an inflight aerial refueling system includes a refueling coupling for receiving a refueling probe. A plurality of trailing edge support arms are pivotally mounted to the trailing edge portion of the refueling coupling, projecting rearwardly, and a plurality of leading edge support arms are pivotally connected to the refueling coupling forward and outward of the trailing edge support arms. A drogue canopy is connected between the trailing ends of the leading and trailing edge support arms, presenting a projected area, to provide drag. A plurality of cord linkages are secured at one end to the leading edge of the drogue canopy, and are connected at their other end to a rear cord ring mounted to the trailing edge portion of the refueling coupling member. A mechanism is provided for uniformly and symmetrically extending and retracting the cord linkages longitudinally with respect to the refueling coupling member to uniformly and symmetrically change the projected area of the drogue canopy.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates generally to aerodynamic drogues for aerial inflight 
refueling, and more particularly concerns an improved drogue having 
adjustable support arms for a canopy to permit the configuration of the 
drogue to be modified in flight to be useful at different air speeds. 
2. Description of Related Art 
The development of drogues for inflight refueling of aircraft has been 
primarily directed by the need to stabilize a refueling hose trailing from 
a tanker aircraft in a generally horizontal attitude. The drogue provides 
drag for the refueling coupling, which must resist the forward movement of 
a probe from a refueling aircraft. Cone shaped drogues have proved to be 
suitable for low speed inflight refueling; however, it has been found that 
such drogues can generate excessive drag at higher speeds, creating loads 
beyond the hose reel operating capabilities. 
The high amount of drag provided by a drogue for low speed refueling also 
can cause the trail angle of the refueling hose and coupling to become 
flattened. It is desirable that the refueling aircraft not follow directly 
in the wake of the tanker aircraft, because the configuration of a drogue 
which may be appropriate for low air speed refueling can be inappropriate 
for high speed refueling, even if the motion of the refueling coupling can 
be stabilized by aerodynamic designs. 
It has therefore been a common practice to install either a low or high 
speed configuration drogue on the refueling coupling of a tanker aircraft 
on the ground, depending upon whether the aerial refueling is to take 
place at low or high speed, and to land to change the drogue to one of 
another speed configuration when an aircraft needs to be refueled at a 
different speed. Another approach has been to fabricate the ring shaped 
parachute canopy of the drogue of elastic material with openings which 
permit pressure modulation to provide for a constant amount of drag over 
varying speeds. However, such elastic openings have been found to be 
subject to deterioration, which can cause the amount of drag provided by 
the drogue to decrease over time, and can also cause an asymmetrical drag 
configuration to develop. 
It has also been proposed to mount the ring shaped canopy to a spring 
assembly allowing for deflection of the canopy of the drogue to provide 
for a constant amount of drag, so that the drogue can be used at varying 
speeds. Such a spring mounting of the canopy at the trailing edge of the 
fuel coupling or support arms has also been found to be prone to damage 
from contact with a probe of a refueling aircraft, which can interfere 
with the drag configuration and stability of the drogue during the 
inflight refueling operation. 
There is therefore a continuing need for a variable speed drogue which can 
be modified during flight or on the ground to have different drag 
configurations to allow the drogue to be used at high and low speeds, and 
which is not generally susceptible to deterioration or damage from a 
refueling probe. In order to safely control the amount of drag provided by 
the drogue, it would be desirable to be able to adjust the projected area 
of the canopy of the drogue in flight by a mechanism external to the fuel 
coupling for changing the angle of separation of support arms to which the 
canopy is attached. It would be also be desirable that the support arms be 
external to the fuel coupling, to be generally protected from potentially 
damaging contact with a refueling probe. Where the canopy is attached to a 
series of leading and trailing edge support arms, it would also be 
desirable to provide a mechanism for uniformly and symmetrically moving 
the pivot points of the leading edge support arms relative to the trailing 
edge support arms, to change the projected area of the canopy, and to 
consequently adjust amount of drag of the refueling drogue for operation 
at different speeds. It would further be desirable that the drag 
adjustment mechanism be operable remotely or manually, during flight or on 
the ground. The present invention fulfills these needs. 
SUMMARY OF THE INVENTION 
Briefly, and in general terms, the present invention provides for a 
variable speed drogue having a variable amount of drag provided by an 
adjustable area of projection of the drogue canopy, which can be set 
remotely or manually, during flight or on the ground, to provide the 
necessary amount of drag appropriate for different speeds of inflight 
refueling. A drag adjustment mechanism external to the refueling coupling 
is provided for uniformly changing the pivot points of leading edge 
support arms relative to trailing edge support arms, between which the 
canopy is attached. The drag adjustment mechanism can be operated during 
flight while the refueling coupling member is in a stowed position in a 
stowage tube, either mechanically, hydraulically, or electrically. 
The invention provides for a variable speed drogue for use with an inflight 
aerial refueling system having a refueling coupling member for receiving a 
refueling probe. The variable speed drogue includes a plurality of 
trailing edge support arms pivotally mounted to the trailing edge portion 
of the refueling coupling member and projecting rearwardly from the 
refueling coupling member. A plurality of leading edge support arms also 
project rearwardly with respect to the refueling coupling member, 
pivotally mounted to the refueling coupling member radially outwardly and 
forward of the trailing edge support arms at a plurality of pivot mounting 
points. 
A drogue canopy is connected between the trailing ends of the leading and 
trailing edge support arms, presenting projected area, to provide drag. A 
plurality of cord linkages are secured at one end to the inside of the 
drogue canopy at or near the outer, leading edge of the drogue canopy, and 
are slidably secured to the inside of the drogue canopy at a plurality of 
selected points in line with the trailing edge arms by cord loops, rings, 
tubes or the like. The cord linkages are connected at their other end to a 
rear cord ring mounted to the trailing edge portion of the refueling 
coupling member. 
A mechanism is provided for uniformly and symmetrically extending and 
retracting the cord linkages longitudinally with respect to the refueling 
coupling member to uniformly and symmetrically change the projected area 
of the drogue canopy. In a preferred embodiment, the mechanism moving the 
cord ring includes a generally tubular sleeve mounted external to the 
refueling coupling member for movement longitudinally with respect to the 
refueling coupling member. A forward sleeve cord ring is provided on a 
trailing edge of the sleeve, and the cord linkages loop around the forward 
sleeve cord ring to extend rearwardly and radially inwardly of the rear 
cord ring to the drogue canopy. Thus, movement of the sleeve to pull or 
slacken the cord linkages changes the projected area of the drogue canopy, 
to vary the amount of drag provided by the drogue canopy. Latch means are 
connected to the sleeve and the refueling coupling member for setting the 
sleeve in any one of a plurality of positions in a forward or rearward 
longitudinal direction relative to the refueling coupling member. Means 
are provided for moving the sleeve in a forward or rearward direction 
longitudinally relative to the refueling coupling member to set the sleeve 
in any one of the plurality of positions, and preferably includes a means 
in the aerial refueling system for latching the sleeve in a selected 
position. The sleeve preferably has a high drag, low speed position and a 
low drag, high speed position, although other intermediate speed settings 
of the sleeve may also be provided. 
These and other aspects and advantages of the invention will become 
apparent from the following detailed description, and the accompanying 
drawings, which illustrate by way of example the features of the invention 
.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
It has been found that the configuration of inflight refueling drogues for 
low and high speed refueling, is important to avoid oscillation and 
instability at high speeds, and to provide the proper trail angle for the 
flight speed during refueling. Landing for changing of the appropriate low 
or high speed configuration drogues on the ground between refueling of 
aircraft inflight at different speeds can be tedious and time consuming. 
Conventional parachute canopies with elastic openings and spring 
assemblies to provide for a constant amount of drag over varying speeds 
are subject to deterioration and damage by contact with a probe of a 
refueling aircraft, interfering with the drag configuration and stability 
of the drogue during the inflight refueling operation. 
With reference to the drawings, in which like reference numerals refer to 
like elements, and which are provided by way of example, the invention 
accordingly provides for a variable speed drogue with a mechanism for 
varying the drag exerted by the drogue external to the refueling coupling, 
that is not generally susceptible to deterioration or damage from a 
refueling probe, and that can be modified during flight for different 
speed configurations. The invention is accordingly embodied in a variable 
speed drogue 20 for use with an inflight aerial refueling system. With 
reference to FIG. 1, the inflight aerial refueling system typically 
includes a fuel supply 22, such as a fuel tank in a tanker aircraft, an 
aircraft drogue stowage tube 24 which can be mounted in a wing pod or 
fuselage of a tanker aircraft for stowing the drogue, and a fuel line 26 
that can be extended and retracted during flight for refueling other 
aircraft, that is connected for fluid communication with the fuel supply. 
The fuel line has a longitudinal axis 28, a leading end 30 connected to 
the tanker aircraft fuel supply, and a trailing end 32 connected to the 
forward end 34 of a refueling coupling member 36. The refueling coupling 
member is generally hollow and conical in shape, with the forward mating 
end portion 34 being attached to the fuel line, a tubular intermediate 
section 38, a tapered intermediate throat section 40 flaring outward 
slightly to the rear of the tubular intermediate section for roller latch 
connection with a refueling probe (not shown) of an aircraft that is 
refueling, and a funnel shaped, tapered mouth portion 42 flaring outwardly 
at the rearward end of the refueling coupling member for receiving the 
refueling probe. The longitudinal axis of the fuel line is generally in 
line with the longitudinal axis 44 of the refueling coupling member where 
they are joined together. 
As is illustrated in FIGS. 1-7, a plurality of trailing edge support arms 
46, each having a leading end 48 and a trailing end 50, are pivotally 
mounted to the trailing edge portion 52 of the refueling coupling member, 
and are adapted to extend outwardly at an angle a with respect to the 
longitudinal axis of the refueling coupling member, as will be further 
explained below, limited in their outward extension by extension limiting 
means such as cables 54a and 54b, shown in FIG. 2, connecting adjacent 
trailing edge support arms to each other at intermediate points along the 
length the trailing edge support arms. 
In one preferred implementation of the invention, 36 trailing edge support 
arms are arrayed around the trailing edge of the refueling coupling 
member. The trailing edge portion of the refueling coupling member 
preferably includes a plurality of inner flanges 56 symmetrically arrayed 
around the trailing edge portion of the refueling coupling member, each of 
the flanges having an aperture 58 in which a first, inner fixed attachment 
ring 60 is mounted. The leading ends of the trailing edge support arms 
include an aperture (not shown) through which the first fixed attachment 
ring also extends, for pivotal mounting of the trailing edge support arms 
to the refueling coupling member. 
A plurality of leading edge support arms 62, each having a leading end 64 
with a proximal aperture (not shown) therethrough, and a distal, trailing 
end 66, are pivotally mounted to the refueling coupling member by 
connection to outer flanges 68 pivotally connecting the proximal ends of 
the leading edge support arms to the refueling coupling member. In the 
preferred embodiment, where 36 trailing edge support arms are provided, 18 
moveable leading edge support arms are provided, each of the moveable 
support arms being interspersed between two of the trailing edge support 
arms. The pivot points at the proximal ends of the leading edge support 
arms are typically spaced apart from the proximal ends of the trailing 
edge support arms by about three inches. 
A plurality of cord linkages or lanyards 70 provide a linkage between the 
drag adjusting mechanism and the drogue canopy. In one currently preferred 
embodiment, there are 18 cords, one for every other trailing edge support 
arm. The cord linkages are preferably arranged in alignment with the 
leading edge support arms, separated by alternating trailing edge support 
arms. As can best be seen in FIGS. 1, 2, 4 and 10, the cord linkages each 
have a forward end 72 secured to a rear cord ring 74 that can be mounted 
by a flange 76 adjacent to the trailing edge of the refueling coupling 
member. Referring to FIG. 14, showing a portion of the drogue canopy 80, 
the plurality of cord linkages are preferably secured at their opposite 
end 78, such as by a knot or the like, to the inside of the drogue canopy 
80 adjacent to the leading edge 82 of the drogue canopy by fastening means 
84. Alternatively, the cord linkages can continue on and be secured to the 
leading edge 82 of the drogue canopy by fastening means at that point, or 
the cord linkages could in certain instances be secured to intermediate 
fastening means that are more removed from the leading edge 82 of the 
drogue canopy. The plurality of cord linkages are also preferably slidably 
secured to the inside of the drogue canopy at a plurality of selected 
points in line with the trailing edge arms by the fastening means 84. In a 
currently preferred embodiment, the fastening means comprises a row of 
eleven nylon loops attached, such as by stitching to the drogue canopy, 
each row of loops being in line with one of the leading edge support arms, 
and in line with the corresponding trailing edge arm. Alternatively, the 
fastening means can comprise other numbers of fasteners, and similar 
common fasteners, such as cord loops of other types of material, stainless 
steel rings attached by such loops to the drogue canopy, tubes or the 
like. As is best illustrated in FIGS. 2-7, when the drogue canopy is 
deployed, the drogue canopy has a scalloped leading edge, and forms a 
series of scalloped, radial stabilization pockets 86. The scalloping 
extends rearward from the leading edge of the drogue canopy to the forward 
fastening means, and continues rearwardly through the folds and radial 
stabilization pockets that are produced, to the trailing edge of the 
drogue canopy. The stabilization pockets are most pronounced and most 
effective in the high speed position, in which the folds of the drogue 
canopy are gathered together, so that the pockets inflate, becoming cells 
of dynamic pressure. The net effect is that the dynamic behavior of the 
drogue canopy is broken down into many smaller components, substantially 
improving the stability of the drogue, particularly at high speed. This 
stabilizing effect is believed to occur due to the limitation of changes 
in dynamic pressure to multiple small areas rather than to a single large 
area, as occurs with presently existing drogues. 
A moveable, generally tubular sleeve 88, covered by a conical, protective 
shroud 90 shown in FIGS. 8 and 13, is mounted to the forward end of the 
refueling coupling member, and is movable longitudinally with respect to 
the refueling coupling member. A forward sleeve cord ring 92 is also 
mounted to a trailing edge flange 94 of the sleeve. In a preferred 
embodiment, the cord linkages extend from the rear cord ring 74 on the 
trailing edge of the refueling coupling member forward to loop around the 
sleeve cord ring 92, then rearwardly and radially inwardly of the rear 
cord ring 74, and through a plurality of protective tubes 96 mounted to 
the trailing edge support arms, such as by welding, extending outwardly of 
and approximately the length of the trailing edge arms through the 
plurality of fastening means. The other end of the cord linkages 70 are 
finally secured to an outermost, most forward fastening means 84 on the 
drogue canopy adjacent the leading edge of the drogue canopy, such as by 
knots or the like, to provide a 2 to 1 mechanical advantage, so that 
movement of the sleeve one inch pulls or slackens the cord linkages two 
inches, changing the projected area of the drogue canopy, to vary the 
amount of drag provided by the drogue canopy. Alternatively, this 2 to 1 
mechanical advantage may not be necessary, and it would also possible to 
secure the cord linkages directly between the sleeve and the drogue 
canopy, without looping from the rear cord ring on the refueling coupling 
around the forward cord ring on the sleeve. 
Referring to FIG. 14, the drogue canopy member 80 is preferably a parachute 
type of canopy attached to the trailing ends of the leading edge support 
arms and the trailing end of the trailing edge support arms, such as by 
nylon cords (not shown), although a cable, hooks or loops, or the like may 
also be suitable. For example, cords attaching the drogue canopy member to 
the leading edge support arms typically passes through channels (not 
shown) and apertures 98 in the leading edge 82 of the drogue canopy 
member, and passes through corresponding distal apertures 106 in the 
trailing ends of the leading edge support arms. Similarly, cords attaching 
the drogue canopy member to the trailing edge support arms typically 
passes through channels (not shown) and apertures 100 in the trailing edge 
104 of the drogue canopy member, and passes through corresponding distal 
apertures 108 in the trailing ends of the trailing edge support arms. As 
is best seen in FIGS. 3, 5 and 14, the drogue canopy member preferably 
comprises a ring shaped parachute canopy of the drogue formed of a 
plurality of trapezoidal sections 110 having a slightly larger leading 
edge 82 than the trailing edge. The drogue parachute canopy may for 
example be made from fabric, netting, webbing, or the like, and may be 
made of nylon, or similar materials that are well known in the art. By 
virtue of movement of the sleeve to pull or slacken the cord linkages, the 
drogue presents a variable projected area depending upon the positioning 
of the sleeve, to provide for an appropriate amount of drag force for 
varying refueling flight speeds. 
Typically, a drag force of approximately 1000 lbs. or less is desired at 
all operating speeds ranging from a low speed of 60 knots to a high speed 
of 300 knots or higher. In order to provide the proper drag force, the 
canopy member preferably has a projected area extending between the 
trailing end of the leading edge support arm and the trailing end of the 
trailing edge support arm that can be adjusted. By adjustment of the 
position of the sleeve forward to pull on and take up the cords to gather 
the folds of the stabilization pockets of the drogue canopy member, or 
rearward to slacken and provide a greater length of the cords to open the 
drogue canopy member more fully, the projected area of the drogue canopy 
member between the trailing ends of the two sets of support members can be 
decreased or increased, respectively, to provide the desired amount of 
drag for refueling at various speeds. Typically, the adjustments of the 
variable speed drogue between higher and lower speed positions is 
performed while the system is fully retracted and stowed, although the 
adjustments can also be performed while the system is deployed. The actual 
amount of drag provided by the drogue will is determined by the amount of 
load required. In one preferred embodiment, illustrated in FIGS. 1-5, the 
sleeve can be adjusted between two positions, for example, one in a 
rearward position providing a larger projected area (A.sub.1) for low 
speed refueling, and one in a forward position providing a smaller 
projected area (A.sub.2) for high speed refueling. The sleeve can also be 
adjusted to intermediate positions, as is illustrated in FIGS. 6 and 7, to 
present an intermediate projected area (A.sub.3), to provide an 
intermediate amount of drag for refueling at in intermediate speed. 
With reference to FIG. 8, the sleeve is preferably mounted external to the 
refueling coupling member for movement relative thereto by a plurality of 
support rollers 112 each having a base portion 114 mounted externally on 
said refueling coupling member, and a bearing roller portion 116 adjacent 
to the inner tubular surface of the sleeve, to allow the sleeve to move 
smoothly and uniformly relative to the longitudinal axis of the refueling 
coupling member. In a preferred embodiment, the sleeve has at least a 
forward, high speed position, and a rearward, low speed position, although 
additional intermediate positions can also be provided, as described 
above. 
In one preferred aspect of the invention, the variable speed drogue 
additionally comprises drag adjustment actuator means 118 for moving the 
sleeve 88 longitudinally in a forward or rearward direction with respect 
to the refueling coupling member. A preferred drag adjustment actuator 
means is shown in FIG. 13, mounted at the forward end 120 of stowage tube 
24. The drag adjustment actuator means preferably includes an elongated 
drive rod 122 that can be extended toward a contact surface such as 
contact plate 124 attached to the forward end of the sleeve to push the 
sleeve into a desired position, and retracted. The drive rod is currently 
preferably driven longitudinally in a forward and rearward direction by 
electric drive means such as an electric motor 126, although the drive rod 
may be driven by other means such as a hydraulic system, provided at the 
forward end of the aircraft drogue stowage tube, mechanically, or 
manually, for adjusting the drogue position when the drogue is retracted 
and stowed in the stowage tube. The drag adjustment actuator means can 
thus push against the sleeve actuator contact plate 124, for moving the 
sleeve in a rearward direction and releasing the sleeve, to latch the 
sleeve in one of the desired drag configuration positions. It is also 
possible to operate the latch system of the invention by retraction of the 
fuel line by a typical fuel line retraction and extension system (not 
shown), so as to cause the sleeve contact plate to be pressed against a 
fixed limit stop bar (not shown) similar to the drive rod 122, preferably 
located at the forward end of the aircraft drogue stowage tube. A coil 
compression ejection spring 128 is disposed at the trailing end 32 of the 
fuel line, and is compressed against the limit stop by when the fuel line 
is fully retracted, to allow a quick expulsion of the variable speed 
drogue when released. The drag adjustment actuator means also preferably 
includes means for sensing the position of the sleeve with respect to the 
refueling coupling member, and in a currently preferred embodiment 
includes an elongated sense rod 130 that can be extended toward the 
contact plate 124 of the sleeve to make electrical contact with the 
contact plate, to complete an electrical sensing circuit providing a 
position signal to the control unit 132 for control of the drive rod for 
positioning of the leading edge support arms. The sense rod is currently 
preferably driven longitudinally in a forward and rearward direction by 
electric drive means such as an electric motor 134, although the sense rod 
may be driven by other means such as a hydraulic system, provided at the 
forward end of the aircraft drogue stowage tube. 
The latch mechanism 136 as illustrated in FIGS. 8-11 is preferably 
connected between the sleeve and the refueling coupling for adjustably 
fixing the sleeve in a plurality of positions in a forward or rearward 
direction with respect to the longitudinal axis of the refueling coupling 
member. In the preferred embodiment, the latch mechanism includes a latch 
bar 138, pivotally connected to the refueling coupling member by a pivot 
bushing 140, having an aperture 142 therein, at the trailing end of the 
latch bar, to a post 144 received in the aperture 142. The post is 
preferably mounted externally on the refueling coupling member, as can 
best be seen in FIG. 9. A detent roller or bearing 146 is mounted at the 
other end of the latch bar, and latch springs 148 mounted to inner flanges 
150 on the sleeve are connected to an intermediate portion of the latch 
bar to bias the latch bar in a centered position, while allowing the latch 
bar to pivot as the detent roller encounters and interacts with a latch 
guide member 152 secured to the sleeve. The latch guide member is 
preferably formed generally in the shape of a triangle positioned at an 
oblique angle with respect to the orientation of the latch bar, with a 
leading side 154 shown away from the latch bar, a trailing side 156 shown 
nearest to the latch bar, a narrow angle 158 shown adjacent to the latch 
bar, and at least one notch 160, in the leg 162 of the triangular guide 
member opposite the narrow angle. The latch guide member is mounted in a 
housing 164 secured to the sleeve. The housing also preferably contains at 
least one guide post 166 adjacent to the notch 160, and additional guide 
features such as guide block 162 on the leading side of the housing, to 
assist in guiding the roller of the latch bar into and out of the notch as 
the latch is operated. Biasing means, such as coil compression springs 
164, which are preferably three symmetrically arranged compression 
springs, are connected between the sleeve contact plate and the refueling 
coupling member to bias the sleeve and guide member housing in a forward 
position, and to therefore bias the latch bar in a rearward position 
relative to the guide member, for placement of the variable speed drogue 
in a high speed configuration. 
From the position shown in FIG. 11, operation of the drive rod to move the 
sleeve and guide member housing rearwardly moves the latch roller along 
the trailing side of the guide member 152 into the guide notch, to latch 
the sleeve in a rearward, low speed position. Operation of the drive rod 
again moves the sleeve and guide member housing rearwardly to unlatch the 
latch roller out of the guide notch. When the drive rod is released, the 
compression springs bring the sleeve and guide member housing forward and 
the latch roller back along the leading side 154 of the guide member, to 
finally rest against the guide block feature 162 with the sleeve in a 
forward, high speed position again. 
With reference to FIGS. 15 and 16, in an alternate preferred embodiment of 
the variable speed drogue, the drogue canopy member is slidably connected 
to the leading edge support arms by a plurality of support arm cords. The 
variable speed drogue 220 is otherwise substantially similar to the 
embodiment depicted in FIGS. 1-14. Thus, in this embodiment, the fuel line 
226 is connected to the forward end mating portion 234 of the refueling 
coupling member 236, and the plurality of trailing edge support arms 246 
are pivotally mounted to the trailing edge portion 252 of the refueling 
coupling member by the fixed attachment ring 260 secured to the refueling 
coupling member by inner flanges 256. The plurality of leading edge 
support arms 262 are pivotally mounted to the refueling coupling member by 
connection to outer flanges 268. 
A plurality of cord linkages 270 extend between the drag adjusting 
mechanism and the drogue canopy, and have a forward end 272 connected to a 
rear cord ring 274 mounted at or near the trailing edge of the refueling 
coupling member. The plurality of cord linkages are secured at their 
opposite end 278 to the inside of the drogue canopy 280 at or adjacent to 
the leading edge 282 of the drogue canopy by fastening means 284, and are 
slidably secured to the inside of the drogue canopy at a plurality of 
selected points in line with the trailing edge arms by fastening means 
284, that are typically stainless steel rings attached in rows by nylon 
loops to the drogue canopy, each row of rings being in line with one of 
the leading edge support arms, and in line with the corresponding trailing 
edge arm. 
As is illustrated in FIGS. 15 and 16, when the drogue canopy is deployed, 
the drogue canopy forms a series of radial stabilization pockets 286. The 
generally tubular sleeve 288 mounted to the forward end of the refueling 
coupling member is movable longitudinally with respect to the refueling 
coupling member, and a forward sleeve cord ring 292 is mounted to a 
trailing edge flange 294 of the sleeve. The cord linkages extend from the 
rear cord ring 274 on the trailing edge of the refueling coupling member 
forward to loop around the sleeve cord ring 292, then rearwardly and 
radially inwardly of the rear cord ring 274, and through a plurality of 
protective tubes 296 connected to the trailing edge support arms, such as 
by welding, extending outwardly of and approximately the length of the 
trailing edge arms through the plurality of fastening means. The 
protective tubes can also be formed as part of the trailing edge arms, 
such as by extrusion. The other end of the cord linkages 270 are secured 
to the forward fastening means 284 on the drogue canopy adjacent the 
leading edge of the drogue canopy, such as by knots or the like, providing 
a 2 to 1 mechanical advantage. 
The drogue canopy member 280 is preferably a parachute type of canopy 
attached to the trailing ends of the trailing edge support arms, such as 
by cords or cables, and the like, extending through apertures in the 
trailing ends of trailing edge support arms. However, the drogue canopy 
member is slidably connected to the trailing ends of the leading edge 
support arms by support arm cords 286, such as nylon cords, extending 
between the trailing ends of the leading edge support arms and the 
trailing ends of the trailing edge support arms, although cables or the 
like may also be suitable. The support arm cords 286 typically pass 
through the rows of fastening means 284. Adjustment of the position of the 
sleeve rearwardly to slacken the cord linkages releases the drogue canopy 
member slide to be fully opened by the force of the air on the drogue 
canopy member to provide a larger projected area for low speed refueling. 
Adjustment of the position of the sleeve to a forward position pulls on 
the cord linkages to reign in the drogue canopy member, reducing projected 
area of the drogue canopy member. As before, the sleeve can also be moved 
to intermediate positions, to provide an intermediate amount of drag for 
refueling at intermediate speeds. 
It should be evident from the foregoing that the variable speed drogue of 
the invention can be modified during flight to have different speed 
configurations, by a mechanism external to the refueling coupling member 
which are thus generally protected from potentially damaging contact with 
a refueling probe form a refueling aircraft. It is significant that the 
variable speed refueling drogue is thus not generally susceptible to 
deterioration or damage from a refueling probe. It is also significant 
that the projected area of the canopy of the drogue can be adjusted by 
increasing or decreasing the projection of the leading edge support arms 
uniformly and symmetrically, to consequently change the drag of the 
refueling drogue for operation at different speeds. The drag adjustment 
mechanism can be operated by a mechanical, hydraulic, or electric drive, 
to allow the drag configuration to be adjusted remotely during flight, or 
can be operated by hand for ready reconfiguration on the ground or manual 
operation in flight. 
It will be apparent from the foregoing that while particular forms of the 
invention have been illustrated and described, various modifications can 
be made without departing from the spirit and scope of the invention. 
Accordingly, it is not intended that the invention be limited, except as 
by the appended claims.