Mechanically braked towed vehicle deployment device

This invention relates to a mechanically braked vehicle deployment device. The deployment device comprises a spool member having a guide member rigidly connected thereto. A tow line is bifilar wound about the spool member in a manner wherein one end of the tow line extends through the guide member and is attached to an aircraft while the other end extends from the spool member and is attached to a towed vehicle. The towed vehicle and the deployment device are deployed simultaneously, and the spool, by nature of its bifilar winding, assumes a position between the aircraft and the towed vehicle. A braking assembly is interfaced to the spool member in a manner operable to provide a braking force during payout of the towed vehicle to control the rotational speed of the spool during tow line payout. At the end of the towed vehicle payout, the deployment device is adapted to disengage itself from the tow line and propel itself away from the tow line and clear of the towed vehicle.

FIELD OF THE INVENTION 
The present invention relates generally to towed vehicles such as aerial 
targets and decoys and more particularly to a mechanically braked towed 
vehicle deployment device used to deploy such towed vehicles behind 
military aircraft. 
BACKGROUND OF THE INVENTION 
In military applications, two types of towed vehicles are well-known and 
often used for weapon/gunnery practice and aircraft protection. These are 
aerial towed targets and aerial towed decoys, respectively. Aerial towed 
targets are typically towed behind an aircraft and used in conjunction 
with pilot weapon training exercises. Aerial towed decoys are used to draw 
various types of guided weapons away from an aircraft that the weapons are 
intended to destroy and/or used to evaluate effectiveness of guided weapon 
systems. Examples of an aerial target and aerial decoy are shown in U.S. 
Pat. No. 4,205,848 to Smith et al. and U.S. Pat. No. 4,852,455 to Brum, 
respectively. 
Both aerial towed targets and decoys typically include electronic devices 
and circuitry incorporated therein. In this respect, aerial towed targets 
include various electronic devices which are used for purposes of scoring 
the pilot's performance during a training exercise. The decoys contain 
various types of electronic circuits which are operable to create an 
apparent target to a weapon to attract the weapon to the decoy, rather 
than the aircraft. One such electronic device is a transponder which is 
adapted to receive radar signals and re-broadcast an amplified return 
signal. The transponder is designed to present a larger electronic target 
than the aircraft from which it is deployed and thereby attract the weapon 
away from the aircraft. 
In those deployment systems in which the towed vehicle is electrically 
interfaced to the aircraft, the electronic data transmission between the 
towed vehicle and aircraft is typically facilitated via the tow line used 
to interconnect the towed vehicle to the aircraft. Data transmitting tow 
lines as currently utilized generally comprise a core of standard 
conducting material extending throughout the tow line forming an 
electrical communication line between the towed vehicle and the aircraft. 
As the programming of anti-aircraft weaponry becomes more sophisticated to 
better discriminate between decoys and aircraft, the need to provide 
decoys within enhanced electrical capabilities similarly evolves. 
Additionally, as fighter weaponry becomes more advanced, it is likewise 
necessary to supply targets with enhanced data transmission and receiving 
capabilities. Thus, it is increasingly necessary for the tow line to 
transmit greater amounts of data and to conduct such transmission at a 
faster rate. 
Further electrical conducting materials as currently utilized in data 
transmitting tow lines are highly susceptible to RF (radio frequency) 
interference which diminishes the data transfer capability of the tow 
line. It has been found that the shortcomings of conventionally known data 
transmitting tow lines can be overcome through the use of a tow line 
having a fiber optic core to establish the communications link between the 
aircraft and the towed vehicle. Such a fiber optic link has the advantage 
of providing enhanced data transmission rates as well as eliminating 
susceptibility to RF interference. 
Though some aerial towed targets as currently manufactured are intended to 
be sacrificial, i.e. non-recoverable, others are intended to be 
recoverable. As can be appreciated, decoys by their very nature are 
intended to be sacrificial only, i.e. the tow line is cut at the aircraft 
at the end of a flight or mission. Though decoys and certain varieties of 
aerial towed targets are sacrificial, the need for rapid and reliable data 
exchange between these towed vehicles and the aircraft is of utmost 
importance for the reasons as previously discussed. 
With regard to both recoverable and sacrificial towed vehicles, perhaps the 
most critical stage in the utilization of such towed vehicles lies in 
their initial deployment. The difficulty regarding deployment lies in the 
fact that the tow line must be able to withstand the extreme amount of 
tensile force exerted thereon by the drag of the vehicle during the 
deployment operation, particularly at the end of the payout of the 
vehicle. In one currently known deployment technique, the tow line is 
wrapped or folded at either the aircraft end or the towed vehicle end and 
allowed to pay out freely without braking. This particular deployment 
technique is primarily used in conjunction with sacrificial towed 
vehicles. In using this particular technique, the elasticity of the tow 
line must absorb the kinetic energy arising from the relative velocity of 
the towed vehicle to the aircraft at the end of the towed vehicle payout. 
As can be appreciated, oftentimes the tow line will snap during 
deployment, rendering the towed target or decoy irretrievably lost. 
Additionally, this particular deployment technique is only effective at 
relatively low aircraft speeds since at higher aircraft speeds, the mass 
of the tow line itself prevents full use of its elasticity which typically 
results in line failure at the end of the payout. Additionally, this 
particular technique does not lend itself to the transmission of power and 
electronic information through the tow line, the importance of which has 
been previously discussed. Since the tow line must possess such a high 
degree of elasticity so as not to snap, the line itself will typically 
cause the conductors within it to fail when it stretches. Thus, a tow line 
having a fiber optic core could not be used since the tow line elasticity 
would cause a failure of the fiber optics when the vehicle is deployed. 
A second technique of deploying both sacrificial and recoverable towed 
vehicles involves the fixing of spools at either the aircraft or the towed 
vehicle to control the payout and braking of the tow line. In this 
respect, the tow line is wrapped about the spool and allowed to be payed 
out in a controlled manner. An example of a first deployment system which 
is operated in this manner and intended to be used in conjunction with 
sacrificial towed vehicles (i.e. decoys) is shown in U.S. Pat. No. 
4,852,455 to Brum. In this particular system, the decoy is initially 
stored within a canister which is permanently attached to the aircraft. 
The canister includes a spool rotatably connected thereto about which the 
tow line is wound. The decoy is released from the canister via an 
explosive charge, and payed out behind the aircraft through the rotation 
of the spool. Centrifugal brakes are provided within the canister to 
oppose the rotation of the spool and thereby regulate the reeling payout 
speed of the deployed tow line. The tow line is adapted to communicate 
electrical signals to the decoy to regulate the operation of the 
electrical circuitry disposed therein. Electrical signals which are 
intended to be passed to the decoy through the tow line are communicated 
to the canister via one or more pin connectors. The pin connectors are 
interfaced to complimentary dynamic slip rings which are interfaced to the 
spool and tow line in a manner operable to transfer the electrical signals 
from the aircraft to the tow line and hence the decoy. 
A second type of deployment system which utilizes the second technique and 
is used primarily With recoverable aerial targets comprises a 
bi-directional reeling machine. Examples of such reeling machines are 
shown in U.S. Pat. No. 4,770,368 to Yates et al.; U.S. Pat. No. 2,760,777 
to Cotton; U.S. Pat. No. 2,778,584 to Wilson; U.S. Pat. No. 2,892,599 to 
Baldwin et al.; and U.S. Pat. No. 2,751,167 to Hopper. Such reeling 
machines typically utilize electric motors, as well as other types of 
supplementary power devices and brakes which are interfaced to a spool in 
a manner operable to reel equipment in and out from an aircraft. 
Additionally, some of these reeling machines are powered by means of an 
air driven turbine interfaced to a spool which can take advantage of the 
available power produced by the ram air energy impinging upon the device 
during aircraft flights. The aforementioned references all comprises 
reeling systems which are adapted to be permanently affixed to the 
aircraft. With regard to the paying out of the towed vehicle, the Cotton, 
Wilson and Baldwin references all disclose fixed pitch turbine blade 
design concepts with various means of throttling the air mass flow through 
the turbine in order to solely control the reel in rate and not the reel 
out rate of the towed vehicle. In this respect, Cotton controls reeler 
payout by means of a motor applied friction brake while Wilson and Baldwin 
rely upon centrifugally applied friction brakes to control reel out rate 
or speed which function in a manner substantially identical to that as 
previously discussed with respect to the Brum reference. The Hopper 
reference discloses a variable pitch turbine in which the blades of the 
turbine may be rotated to various attack angles to provide torque for reel 
in or provide opposing torque for reel out applications. However, this 
variable pitch turbine blade design is extremely expensive and requires 
constant operator monitoring of turbine speed and hence, has not been 
widely utilized in the prior art. The alternative disclosed in Hopper, 
i.e. having a fixed pitch turbine coupled to a reversing gear train to 
achieve reel in, reel out bi-directional operation give rise to the 
complexity of a reversing gear train which has likewise prevented the 
design's widespread use. 
It will be appreciated that the aforementioned bi-directional reeling 
devices adapted to reel in and reel out towed vehicles are generally not 
used in conjunction with sacrificial vehicles in that there is typically 
no need to reel in a sacrificial vehicle. To the extent that these devices 
are used with towed vehicles requiring an electrical interface to the 
aircraft, electrical transfer mechanisms similar to that previously 
discussed with regard to the Brum reference, i.e. slip rings, are 
typically incorporated into these devices for purposes of conducting 
electrical data transfer. 
Though the unidirectional and bi-directional reeling devices are operable 
to pay out the towed vehicle at a controlled rate, the use of slip rings 
for data transmission purposes does not lend itself to the use of tow 
lines incorporating fiber optics. Thus, the aforementioned reeling devices 
are not typically able to provide the enhanced data transmission 
capabilities facilitated by a fiber optic link. Such reeling devices also 
require high amounts of maintenance to insure the proper functioning of 
the braking mechanisms. Additionally, the use of such reeling devices 
necessitates the permanent affixation of a spool and brake assembly to the 
aircraft. 
SUMMARY OF THE INVENTION 
The present invention is specifically directed toward meeting the 
aforementioned shortcomings in towed vehicle deployment systems. In the 
present invention, the tow line is fixed at both the aircraft and towed 
vehicle ends of the tow line thereby eliminating the need for slip rings. 
The tow line is stowed on a bifilar wound spool disposed along the length 
of the tow line such that the aircraft and towed vehicle ends of the tow 
line are simultaneously unwound during payout. The towed vehicle and the 
spool are deployed simultaneously and the spool, by nature of its 
wrapping, assumes a position between the aircraft and the towed vehicle. 
The spool provides braking force during payout to deploy the towed vehicle 
at a controlled rate within system parameters to insure that throughout 
payout and particularly at full payout, the tensile load applied to the 
tow line is sufficiently small so as to prevent tow line failure. At the 
end of the payout, the spool disengages itself from the tow line and 
propels itself away from the tow line and clear of the towed vehicle. 
More particularly, in accordance with a preferred embodiment of the present 
invention, there is provided a mechanically braked towed vehicle 
deployment device which generally comprises a spool member and a guide 
member rigidly connected to the spool member. The spool member itself 
comprises a sleeve portion which includes an aperture extending axially 
therethrough. A first laterally extending flange portion is formed 
adjacent the first end of the sleeve which defines an outer surface having 
a first spider portion formed thereon. The first spider portion itself 
defines a first set of cavities disposed about the periphery thereof. 
Formed adjacent the second end of the sleeve portion is a second laterally 
extending flange portion which, like the first flange portion, also 
defines an outer surface having a second spider formed thereon. The second 
spider portion has a configuration identical to the first spider portion 
and defines a second set of cavities disposed about the periphery thereof. 
A length of cable (i.e. the tow line) is bifilar wound about the spool 
member in a manner wherein the first end extends through the guide member 
and is attached to an aircraft and the second end is attached to the towed 
vehicle. 
The spool member includes brake means associated therewith which are 
operable to control i.e. slow the deployment of the towed vehicle behind 
the aircraft. The brake means comprise an elongate shaft which is sized 
and configured to be slidably receivable into the aperture defined within 
the sleeve portion. A first drum member defining a first arcuate interior 
surface is positioned over the first spider portion and rigidly connected 
to the first end of the shaft. Similarly, a second drum member defining a 
second arcuate interior surface is positioned over the second spider 
portion and rigidly connected to the second end of the shaft. Inserted 
into the first set of cavities defined within the first spider portion are 
a plurality of brake pads. A plurality of brake pads are likewise inserted 
into the second set of cavities defined within the second spider portion. 
In operation, the rotation of the sleeve portion about the shaft is 
operable to cause each of the brake pads to move radially outwardly via 
centrifugal force so as to come in abutting contact with the interior 
surface of a respective drum member thereby slowing the rotation of the 
spool member relative the drum members and shaft. 
The guide member is rigidly connected to the first drum member by a first 
connecting member and to the second drum member by a second connecting 
member. The guide member further includes a disengagement or ejection 
means which is operable to release the guide member and hence the spool 
member from the tow line when the towed vehicle is fully deployed. The 
disengagement means preferably comprises a serpentine slot disposed within 
the guide member which is sized and configured to allow the tow line to 
pass therethrough when the guide member is pulled downwardly against the 
tow line. 
Importantly, the first connecting member and the second connecting member 
are sized and configured so as to act as lever arms such that the torque 
created by the rotation of the spool member after the towed vehicle has 
been fully deployed will pull the guide member toward the tow line in a 
manner operable to facilitate the ejection of the guide member from the 
tow line. The tow line itself preferably includes a fiber optic core which 
is adapted to transmit signals between the towed vehicle and the aircraft. 
Advantageously, the bifilar winding of the tow line about the spool member 
is adapted to simultaneously deploy the towed vehicle and the deployment 
device and to maintain the deployment device in a position typically 
equidistantly spaced between the towed vehicle and the aircraft while the 
towed vehicle is being deployed. The sleeve portion includes a groove 
formed therein which is adapted to receive a portion of the tow line in a 
manner operable to initiate the bifilar winding of the tow line about the 
spool member and to cause the spool member to rotate about the shaft while 
the towed vehicle is being deployed. In the preferred embodiment, the 
spool member is constructed from aluminum, the drum members are 
constructed from stainless steel, and the guide member is constructed from 
Teflon. 
It is an object of the present invention to provide a vehicle deployment 
device adapted to deploy a towed vehicle at a controlled rate of speed. 
Another object of the present invention is to provide a towed vehicle 
deployment device having enhanced electronic data transmission 
capabilities. 
Another object of the present invention is to provide a towed vehicle 
deployment device which is disposable and eliminates the need for the 
permanent attachment of a deployment mechanism to the aircraft or to the 
towed vehicle.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring now to the drawings wherein the showings are for purposes of 
illustrating a preferred embodiment of the present invention only, and not 
for purposes of limiting the same, FIG. 1 perspectively illustrates the 
mechanically braked vehicle deployment device 10 of the present invention 
positioned on a tow line 12 as a towed vehicle 14 is being payed out 
behind an aircraft 16. Towed vehicle 14 as used with deployment device 10 
is typically a sacrificial towed vehicle such as an aerial target or a 
decoy. Thus, towed vehicle 14 is intended to be released from aircraft 16 
as opposed to being reeled back toward aircraft 16. Additionally, towed 
vehicle 14 will typically be of a variety incorporating electronic devices 
and circuitry therein. As such, tow line 12 is adapted to transmit 
electrical data from aircraft 16 to towed vehicle 14. In the preferred 
embodiment, tow line 12 has a fiber optic core to facilitate such data 
transmission, however more conventional electrical data transmission 
systems such as metal conductors are also contemplated. The inclusion of a 
fiber optic core within tow line 12 enhances the electrical data 
transmission capabilities between the aircraft 16 and the towed vehicle 14 
by increasing the amount of data that may be transmitted through tow line 
12 as well as increasing the speed at which such data is transmitted. 
Additionally, the fiber optic communications link is not susceptible to RF 
(radio frequency) interference as are other more conventional types of 
conducting/transmission materials. It will be appreciated, however, that 
towed vehicle 14 need not necessarily incorporate electrical devices 
therein, and that tow line 12 may be constructed in a manner so as not to 
include any electrical conducting capabilities. 
Referring now to FIG. 2, deployment device 10 generally comprises a 
rotatable spool member 18 having a guide member 20 interfaced thereto. As 
will be discussed in greater detail below, the tow line 12 is bifilar 
wound about the spool member 18 in a manner wherein a first end 12a of tow 
line 12 extends through guide member 20 and is attached to aircraft 16 
while the second or opposite end 12b is attached to towed vehicle 14. 
Since the tow line 12 is fixed at both the aircraft and towed vehicle ends 
of the tow line 12, the need for slip rings or other similar rotary 
interface devices to facilitate any desired electrical data transmission 
between the aircraft 16 and the towed vehicle 14 is eliminated. 
Additionally, on the basis of the tow line 12 being bifilar wound about 
the spool member 18, the ends of the tow line 12 attached to the towed 
vehicle 14 and aircraft 16 are simultaneously unwound during payout. Since 
the towed vehicle 14 and deployment device 10 are deployed simultaneously, 
by nature of the bifilar winding of the tow line 12 about the spool member 
18, the deployment device 10 assumes a position between the aircraft 16 
and towed vehicle 14 during payout of the towed vehicle 14. 
Referring now to FIGS. 3-5, spool member 18 generally comprises a sleeve 
portion 22 which includes an aperture extending axially therethrough. 
Formed adjacent a first end of sleeve portion 22 is a first laterally 
extending flange portion 24 which defines a generally planar outer surface 
24a. Formed on outer surface 24a is a first spider portion 26 which 
defines a plurality of rectangularly configured cavities 28 extending 
about the periphery thereof. Formed adjacent the second end of sleeve 
portion 22 is a second laterally extending flange portion 30 which, like 
first flange portion 24, also defines a generally planar outer surface 
30a. Formed on outer surface 30a of flange portion 30 is a second spider 
portion 32 which has a configuration identical to first spider portion 28. 
In this respect, second spider portion 32 defines a plurality of generally 
rectangular cavities 34 about the periphery thereof. Inserted into one or 
more of the cavities 28 defined within first spider portion 26 are brake 
pads 36. Though not shown, brake pads 36 are also disposed within one or 
more of the cavities 34 defined within second spider portion 32. Brake 
pads 36, which are preferably constructed from conventional brake lining 
material, are used in conjunction with the braking mechanism in a manner 
which will be described in greater detail below. 
Disposed within the aperture extending axially through sleeve portion 22 is 
an elongate shaft member 38 which includes a first axially extending 
aperture 40 in one end thereof and a second axially extending aperture 42 
in the opposite end thereof, each of which are internally threaded. Shaft 
member 38 is slidably received and adapted to rotate relative sleeve 
portion 22 and has a length such that each end protrudes slightly 
outwardly beyond the spider portion through which it extends. Positioned 
about each exposed portion of the shaft member 38 are thrust washers 44. 
One such thrust washer 44 is illustrated in FIG. 3. A first drum member 46 
defining a first arcuate interior surface 46a is positioned over the first 
spider portion 26 and rigidly connected to the first end of shaft member 
38 by a first screw fastener 48 which is threadably received into first 
aperture 40. Importantly, first drum member 46 is sized and configured 
such that there is only a slight radial distance separating first arcuate 
interior surface 46a from the periphery of first spider portion 26. A 
second drum member 50 defining a second arcuate interior surface 50a is 
positioned over second spider portion 32 and rigidly connected to the 
second end of shaft member 38 by a second screw 52 which is threadably 
received into second aperture 42. Like first drum member 46, second drum 
member 50 is also sized and configured such that there is only a slight 
radial distance separating second arcuate interior surface 50a from the 
periphery of second spider portion 32. 
As previously specified, tow line 12 is bifilar wound about the spool 
member 18. In this respect, formed within the outer surface of sleeve 
portion 22 is a groove 54 which is adapted to receive a central portion of 
tow line 12 in a manner operable to initiate the bifilar winding of tow 
line 12 about sleeve portion 22 in the manner shown in FIG. 4. 
Guide member 20 is connected to first drum member 46 by a first connecting 
member 56 and to second drum member 50 by a second connecting member 58. 
In the preferred embodiment, first connecting member 56 and second 
connecting member 58 are formed as integral portions of first drum member 
46 and second drum member 50, respectively, though it will be appreciated 
that connecting members 56, 58 may be independent components attached to a 
respective drum member by a welding operation or other fastening 
procedure. First connecting member 56 and second connecting member 58 are 
interfaced to first drum member 46 and second drum member 50, 
respectively, in a manner such that their distal ends terminate in 
approximately the same location. Formed on the distal end of first 
connecting member 56 is a first elongate coupling portion 60 having a 
generally rectangular configuration. Similarly, disposed on the distal end 
of second connecting member 58 is a second coupling portion (not shown) 
which has a configuration identical to first coupling portion 60. First 
coupling portion 60 and the second coupling portion are configured in a 
manner so as to extend generally parallel to one another while being 
separated by a relatively narrow gap. 
Guide member 20 generally comprises a tubular portion 62 having a bore 64 
through which one end of tow line 12 is adapted to extend. As best seen in 
FIG. 6, the diameters of the opposed ends of bore 64 are preferably formed 
significantly greater than the diameter of the center portion defining a 
bell shaped annular transition to aid in allowing tow line 12 to be easily 
pulled axially therethrough during deployment of the towed vehicle 14. 
Extending outwardly from the outer surface of tubular portion 62 is a 
flange 66 having apertures 68, 70 disposed therein. Flange 66 is sized to 
have a thickness such that it may be inserted into the gap defined between 
first coupling portion 60 of first connecting member 56 and the second 
coupling portion of second connecting member 58. Apertures 68, 70 are 
disposed within flange 66 in an orientation such that they will be in 
coaxial alignment with pairs of apertures disposed within first coupling 
Portion 60 and the second coupling portion. Screw fasteners 72, 74 are 
then placed within the coaxially aligned holes and apertures to facilitate 
the attachment of guide member 20 to first connecting member 56 and second 
connecting member 58. Additionally, disposed within the tubular portion 62 
of guide member 20 is a serpentine shaped slot 76, the use of which will 
be discussed in greater detail below. 
Having thus described the components of deployment device 10, the operation 
thereof will now be discussed. Initially, the tow line 12 is preferably 
folded in half and the loop portion formed by the fold is inserted into 
groove 54 as seen in FIG. 3. As tow line 12 is being wound about sleeve 
portion 22, it is constantly moved from side to side between first flange 
portion 24 and second flange portion 30 so as to maintain an even 
distribution of the tow line 12 windings about sleeve portion 22. After 
the winding operation has been completed, one end of tow line 12 is 
extended over the winds on the spool and is attached to the towed vehicle 
14 while the other end of the tow line is extended under the winds on the 
spool at a 180 degree orientation to the first end, inserted through guide 
member 20 and attached to aircraft 16. After the aircraft 16 is in flight, 
the deployment device 10 and towed vehicle 14 are simultaneously ejected 
from the aircraft 16. The velocity of aircraft 16 in conjunction with the 
drag exerted on towed vehicle 14 causes towed vehicle 14 to be payed out 
behind the aircraft 16. 
Referring now to FIG. 7, as previously specified, the bifilar winding of 
tow line 12 about sleeve portion 22 of spool member 18 causes the opposed 
ends of the tow line 12 to be simultaneously unwound during payout of the 
towed vehicle 14 behind the aircraft 16. Thus, since deployment device 10 
is only attached to tow line 12, the payout of the towed vehicle 14 will 
cause the spool member 18 to begin rotating in the direction shown in FIG. 
7 during the payout process. Since shaft member 38 is rigidly connected to 
drum members 46, 50 which are in turn rigidly connected to guide member 
20, the positioning of guide member 20 about the tow line prevents any 
component of deployment device 10 other than spool member 18 from 
rotating. In this regard the guide member positively captures the tow line 
therein while allowing axial movement of the tow line therethrough. During 
the payout process, and dependent upon aircraft flight speed and system 
parameters the spool member rotates at a controlled speed preferably 
approximately 5,000-20,000 RPM about shaft member 38. This high speed of 
rotation causes each of the brake pads 36 inserted into the cavities 28 of 
first spider portion 26 and the cavities 34 of second spider portion 32 to 
move radially outwardly via centrifugal force within a respective cavity. 
Such outward radial movement during the rotation of the spool member 18 
causes the brake pads 36 disposed within cavities 28 to come in abutting 
contact with the interior arcuate surface 46a of first drum member 46. 
Similarly, the brake pads 36 disposed within cavities 34 are caused to 
come in abutting contact with the second arcuate interior surface 50a of 
second drum member 50. As can be appreciated, this contact provides a 
frictional braking force during the payout of towed vehicle 14 so as to 
allow deployment of towed vehicle 14 at a rate within system parameters. 
This in turn prevents the failure i.e. breakage of the tow line 12 during 
the deployment of the towed vehicle 14 particularly when it comes to the 
end of payout. Additionally it will be recognized that due to the lateral 
spacing of the guide member from the spool, the braking forces applied to 
the spool are reacted by guide member upon the tow line with the members 
56 and 58 forming a lever arm between the brake drums 46 and 50 and the 
guide member 20. The guide member 20 is positioned over the first end 12a 
of tow line 12 which is attached to the aircraft 16 since first end 12a is 
better capable of reacting to the brake torque. In this respect, the 
tension is higher at the aircraft end 12a than at the towed vehicle end 
12b since the drag of the deployment device 10 itself is superimposed on 
the towed vehicle drag. Guide member 20 also serves to maintain the spool 
axis perpendicular to the airstream thereby promoting an orderly payout of 
the tow line 12. The number of braking pads 36 disposed within cavities 28 
or cavities 34 is determined by the desired amount of braking force that 
is to be applied to spool member 18 during the deployment of towed vehicle 
14. As can be appreciated, as the number of braking pads 36 inserted into 
cavities 28, 34 is increased, the amount of braking force that will be 
applied to spool member 18 will likewise be increased. 
As towed vehicle 14 is being deployed, the velocity at which the tow line 
12 is unwound from spool member 18 and the drag force exerted by towed 
vehicle 14 causes each end of tow line 12 to remain taught during the 
payout of towed vehicle 14. As such, though the end of tow line 12 
extending through guide member 20 is free to axially move within bore 64, 
the tow line 12, due to its taught configuration, is positively capture 
within the guide member 20 and is prevented from traveling through 
serpentine slot 76. 
Referring now to FIGS. 7-9, due to the bifilar winding of tow line 12 about 
spool member 18, when the towed vehicle 14 is fully deployed, the tow line 
12 will be removed from within groove 54 and hence be disconnected from 
spool member 18. When this disconnection occurs, the spool member 18 will 
still be rotating about shaft member 38 at a high rate of speed so its 
centrifugal brakes will still be engaged. In the preferred embodiment, the 
first connecting member 56 and the second connecting member 58 are sized 
and configured to act as lever arms such that the torque created by the 
high rotation of the spool member 18 about shaft member 38 after the towed 
vehicle 14 has been fully deployed will pull guide member 20 against tow 
line 12. This pulling of guide member 20 against tow line 12 is operable 
to alter the angle between the guide member 20 and tow line 12 causing the 
tow line 12 to rapidly move through the serpentine slot 76 in the manner 
shown in FIG. 9. The receipt of tow line 12 into slot 76 is further aided 
by the lead in portion 77 of the serpentine slot 76 and open diameter ends 
of the tubular portion 62 of guide member 20 as previously described. 
After tow line 12 moves completely through serpentine slot 76, the 
deployment device 10 is thereby released from the tow line and is ejected 
i.e. falls away from the tow line 12 in the manner illustrated in FIG. 8. 
As can be appreciated, if the deployment device 10 was not ejected from 
the tow line 12 in this manner, the force of air exerted against the 
deployment device 10 could cause it to accelerate down the tow line 12 to 
impact the towed vehicle 14, thereby damaging or destroying the towed 
vehicle 14. In the preferred embodiment, spool member 18 is constructed 
from aluminum, brake drums 46 and 50 are constructed from stainless steel 
as are connecting members 56 and 58, and guide member 20 is constructed 
from Teflon or nylon. Additionally, deployment device 10 may be oriented 
in a manner wherein the end of tow line 14 extending through guide member 
20 is attached to the towed vehicle 14 as opposed to the aircraft 16, 
although it is not preferable. 
Additional modifications and improvements of the present invention may also 
be apparent to those skilled in the art. Thus, the particular combination 
of parts described and illustrated herein is intended to represent only 
one embodiment of the invention, and is not intended to serve as 
limitations of alternative devices within the spirit and scope of the 
invention.