United States Patent [19]
`Pickett et al.
`
`[11] Patent Number:
`[45] Date of Patent:
`
`4,463,701
`Aug. 7, 1984
`
`[54]
`
`[75]
`
`PARAVANE WITH AUTOMATIC DEPTH
`CONTROL
`Inventors: David M. Pickett, Clarksburg;
`Richard K. Knutson; William
`VonFeldt, both of Gaithersburg, all
`of Md.
`[73] Assignee: The United States of America as
`represented by the Secretary of the
`Navy, Washington, DC.
`[21] Appl. No.: 125,735
`[22] Filed:
`Feb. 28, 1980
`[51] Int. Cl.3 ............................................ .. B63B 21/00
`[52] U.S. Cl. ............................... .. 114/245; 114/331
`[58] Field of Search ............. .. 114/244, 245, 274, 331,
`_
`114/332, 126
`References Cited
`U.S. PATENT DOCUMENTS
`
`[56]
`
`114/245
`2,709,931 6/1955 Wilcoxon
`. 114/244
`3,703,876 11/1972 Michelsen ..
`14/245 x
`.
`3,842,770 10/1974 Hedbawny e
`4,019,453 4/1977 Boswell .............. ............. .. 114/245
`
`4,215,862 8/1980 Yoshikawa m1. .......... ..114/245 x
`Primary Examiner-Trygve M. Blix
`Assistant Examiner-—Stephen P. Avila
`Attorney, Agent, or Firm—-R. F. Beers; L. A. Marsh
`[57]
`ABSTRACT
`A paravane includes an elongated fuselage; a wing sec
`tion of spaced wing members attached to an intermedi
`ate portion of the fuselage; stabilizer ?ns for maintaining
`the paravane lined-up with the direction of tow; a depth
`control ?ap positioned adjacent the wing section and
`having a pivot axis extending closely adjacent to the
`towing point; and depth control means for controlling
`the position of the control flap. The wing members have
`a straight leading edge portion, a straight trailing edge
`portion and a curved intermediate portion wherein the
`wing members are arranged such that the chord lines
`extend at oblique angles with the longitudinal axis of the
`fuselage and such that the resultant hydrodynamic lift
`force vector acting on the wing section passes through
`.
`the tow Pmm'
`
`15 Claims, 6 Drawing Figures
`
`29
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`1
`
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`
`35
`
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`
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`
`3/
`
`PGS v. WESTERNGECO (IPR2014-00689)
`WESTERNGECO Exhibit 2058, pg. 1
`
`

`

`US. Patent Aug. 7, 1984
`
`Sheet 1 of 3
`
`4,463,701
`
`/9
`
`3/
`
`, x
`
`PGS v. WESTERNGECO (IPR2014-00689)
`WESTERNGECO Exhibit 2058, pg. 2
`
`

`

`U.S. Patent Aug. 7, 1984
`
`Sheet 2 of3
`
`“4,463,701
`
`PGS v. WESTERNGECO (IPR2014-00689)
`WESTERNGECO Exhibit 2058, pg. 3
`
`

`

`US. Patent Aug. 7, 1984
`
`Sheet 3 0f3
`
`4,463,701
`
`RV
`
`PGS v. WESTERNGECO (IPR2014-00689)
`WESTERNGECO Exhibit 2058, pg. 4
`
`

`

`1
`
`PARAVANE WITH AUTOMATIC DEPTH
`CONTROL
`
`The invention described herein may be manufactured
`and used by or for the Government of the United States
`of America for governmental purposes without the
`payment of any royalties thereon or therefor.
`
`4,463,701
`2
`for preventing roll motions greater than a preselected
`value are provided which enable the paravane to oper
`ate with a high degree of stability.
`Accordingly, it is an object of the present invention
`to provide a simple, yet efficient towed underwater
`apparatus capable of achieving and maintaining a con
`trolled depth, possessing a high degree of stability, and
`which may be manufactured inexpensively and does not
`require skilled personnel to operate.
`Another object of this invention is the provision of a
`towed underwater device which develops a high out
`ward lift force relative to its size and buoyancy in water
`and which is capable of seeking and maintaining a pre
`determined depth and towing orientation.
`A further object of the present invention is to provide
`a towed underwater apparatus which is highly stable
`over a wide range of speeds and which is capable of
`assuming a predetermined orientation irregardless of its
`initial position.
`Yet another object of this invention is to provide a
`towed underwater apparatus which includes means for
`stabilizing the apparatus with respect to undesirable
`rolling, yawing and pitching actions and means for
`enabling the paravane to maintain a predetermined
`depth without undue stress on the towing apparatus.
`Still another object of the present invention is to
`provide a towed underwater apparatus which utilizes
`depth control means, whereby a large vertical lift force
`can be generated to support the weight of the towing
`cable and attached devices so that depth can be main
`tained even at a low towing speed.
`
`45
`
`50
`
`55
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`The novel features which are believed to be charac
`teristic of this invention are set forth with particularity
`in the appended claims. The invention itself, however,
`both as to its organization and method of operation,
`together with further objects and advantages thereof,
`may be best understood by reference to the following
`description taken in connection with the accompanying
`drawings, in which:
`FIG. 1 is a side view of the paravane in its normal
`operating position;
`FIG. 2 is a front view of the paravane of FIG. 1;
`FIG. 3 is a plan view of the paravane of FIG. 1;
`FIG. 4 is a sectional view, partially broken away, of
`the paravane, depicting the wing members and the con
`trol ?ap;
`FIG. 5 is a sectional view of a wing member; and
`FIG. 6 is a diagram of the depth control system em
`ployed in the paravane.
`
`DETAILED DESCRIPTION OF THE
`DRAWINGS
`Referring now to the drawings, wherein like refer
`ence characters designate corresponding parts through
`out the several ?gures, and particularly to FIGS. 1
`through 3, there is shown a paravane 11 attached to a
`towing cable 8 (see FIG. 3). The paravane 11, which
`resembles a biplane, includes a cylindrical fuselage 12 or
`body; a wing section 21 of spaced wing members 22
`secured to the central portion 14 of the fuselage 12; and
`a control ?ap 31 pivotally connected to the fuselage 12
`and extending generally normal to the planes de?ned by
`the wing members 22. A lateral stabilizer 18 is attached
`to the tail portion 15 of the fuselage 12 and extends in a
`generally perpendicular relationship with the planes
`de?ned by the wing members 22 for maintaining the
`
`25
`
`30
`
`BACKGROUND OF THE INVENTION
`The present invention generally relates to paravanes
`and other underwater towed apparatus and more partic
`ularly to paravanes having wing sections with high
`lift-to-drag and high lift-to-weight ratios and provided
`with means for maintaining the paravanes at a predeter
`mined ordered depth.
`Generally, paravanes towed by minesweepers are
`connected to a cable system so that the paravanes are
`positioned behind and laterally offset from the tow
`point of the minesweeper to maximize the sweep area.
`20
`Various depth control means have been utilized to
`maintain the paravanes at a predetermined depth. One
`type of depth control means utilizes a ?oat device with
`a length of cable extending between the ?oat and the
`paravane such that the operating depth of the paravane
`is controlled by changing the length of the cable. How
`ever, the cable length often limits the effective working
`depth, and the ?oat and cable assembly tends to impose
`undesirable drag forces on the towing vessel. Another
`depth control means which overcomes some of the
`drawbacks with'the abovementioned ?oat controls uti
`lizes a depth sensor which is coupled with a rudder or
`control ?ap, the movement of which causes the para
`vane to ascend or descend. However, some of these
`depth control means as utilized in conventional para
`vane construction have caused the paravane to oscillate
`excessively or “hunt” in the water in ?nding the equilib
`rium position at the desired working depth. Such oscil
`lating action produces dynamic loads and undesirable
`stresses in the cable system.
`Paravanes and other underwater apparatus which
`include various depth control means are generally ex
`empli?ed by US. Pat. Nos. 2,709,981; 2,879,737;
`2,981,220; 3,560,912; and 3,703,876.
`SUMMARY OF THE INVENTION
`The present invention overcomes many drawbacks of
`the prior art by providing a compact, ef?cient paravane
`having a high lift coefficient, a low drag coef?cient,
`good stability over a wide range of towing speeds and
`means for preventing undesired roll motions. This is
`generally accomplished by attaching a wing section of
`highly ef?cient staggered wing members to the fuselage
`such that the resultant lift force vector for the wing
`section is favorably arranged with respect to the towing
`point. The internal space of the fuselage is optimized to
`accommodate various power and control means as well
`as lightweight ballasting materials so that the paravane
`can be made almost neutrally buoyant. counterweight
`means can be attached to one of the wing members so
`that the wing section assumes a vertical orientation in
`the water. Horizontal and lateral stabilizers are attached
`to the tail end portion of the fuselage to provide the
`paravane with stability against pitching and yawing
`motions. A pivotal control ?ap is positioned relative to
`the wing section such that a high degree of roll motion
`is generated for small de?ections of the control flap.
`Depth control means containing a roll override feature
`
`PGS v. WESTERNGECO (IPR2014-00689)
`WESTERNGECO Exhibit 2058, pg. 5
`
`

`

`20
`
`4,463,701
`4
`.
`'
`3
`ber 22 is positioned to pass through the intermediate
`fuselage 12 at a proper operating orientation in the
`portion 24 of the wing member 22.
`water. The paravane 11 further includes a longitudinal
`For an ef?cient wing design it was found that the
`stabilizer 19 secured to one portion of the lateral stabi
`position of maximum camber should occur at or close to
`lizer 18 for maintaining the wing members 22 correctly
`the center of the resultant force vector acting on the
`lined up with the flow.
`wing member 22. The camber line of the wing member
`As generally shown in FIGS. 1 through 3, the fuse
`is de?ned as the line which extends along the centerline
`lage 12, which may be formed of a lightweight yet
`of the wing member 22 from point A to point B, as
`strong material such as aluminum or reinforced plastic,
`shown in FIG. 5, and the chord line is de?ned as the
`comprises, an elongated tubular casing having a hemi
`shortest line which can be drawn from point A to point
`spherical nose portion 13 for maximizing the internal
`B. The camber for the wing is the perpendicular dis
`volume of the fuselage 12 and for providing a stream
`tance from the camber line to the chord line. For the
`lined pro?le in the water. Such internal void spaces not
`particular wing member 22 shown in FIG. 5, the posi
`only serve to accommodate depth control means and
`tion of maximum camber should be located between
`other devices, but the void spaces may be ballasted with
`30% to 40% and preferably between 33% and 35% of
`various lightweight materials, such as syntatic foam,
`the distance between points A and B, as measured from
`such that the paravane 12 will be neutrally buoyant in
`point A on the leading edge 23. It has been observed
`water and balanced about one or more symmetrical
`that when the position of maximum camber varies
`axes. Lightweight syntatic foam materials commonly
`widely from the abovementioned location, the resultant
`include glass microspheres interposed within an epoxy
`lift forces on the wing member 22 will vary widely
`matrix, wherein the material is capable of withstanding
`and/or erratically, with undesirable motions such as
`large hydrostatic pressures applied thereto and it does
`pitching moments being imparted to the wing members
`not absorb appreciable amounts of water. Thus, by
`22. In a particular example of an ef?cient wing design,
`making the paravane 12 neutrally buoyant in water and
`the chord line from point A to point B in FIG. 5 was
`distributing the weight about one or more axes, small
`6.75 inches and the point of maximum camber occurred
`25
`counterweights may be applied to a tip of one wing
`at a distance of 2.25 inches from point A. The length
`member 22, for example, to cause the wing members 22
`ratio of the leading edge portion 23 to the trailing edge
`to assume a vertical position when placed in the water.
`portion 27 was 1:10 with the leading edge 23 having a
`Additionally, the paravane 11, when nearly neutrally
`length of about 0.42 inches and the trailing edge portion
`buoyant, can be towed at extremely slow speeds at a
`27 having a length of about 4.10 inches. The intermedi
`predetermined depth since the resultant weight compo
`ate portion 24 of the wing member subtends an arc of
`nent, which would ordinarily cause the paravane 11 to
`42° with a radius of curvature of approximately 3.09
`sink at slow towing speeds, is nearly zero. It is further
`inches as measured at the convex surface 26. The wing
`understood that small weight elements may be added to
`member 22 was formed with a constant thickness of
`or removed from the paravane 11 so that the buoyancy
`0.375 inches to facilitate economical and easy fabrica
`of the paravane 11 can be adjusted.
`tion.
`To facilitate access to equipment located in the inte
`By using two wing members 22, disposed at a suitable
`rior of the fuselage 12, the nose 13 and/or the tail por
`angle'to the longitudinal axis of the paravane 11 and
`tion 15 may be constructed for easy removal. For exam
`arranged in a staggered pattern, a biplane effect is pro
`ple, access to a depth control means as represented by a
`duced which is highly ef?cient in creating the hydrody
`box 29,» which is shown in broken lines in FIG. 1, may
`namic lift necessary to maintain the paravane 11 at the
`be achieved by unscrewing the nose portion 13 from the
`desired depth and lateral offset from the towed vessel.
`central portion 14 of the fuselage 12. Similarly, a power
`Such arrangement thereby serves to delay the flow
`unit such as a battery or impeller turbine 30, shown
`separation between the wing members 22 and the water
`generally by broken lines in FIG. 1 and designed to
`flow so that the resulting wing envelope is relatively
`supply electricity to the depth control means 29, may be
`small for the high lift forces and low drag forces gener
`attached to the tail portion 15 of the fuselage 12.
`ated by the wing section 21. It was observed, for exam
`The wing section 21, which preferably comprises
`ple, that the total lift force produced by a wing section
`pairs of spaced wing members 22 arranged in the form
`21 at various towing speeds was greater than the sum of
`of a biplane as depicted in the drawings, is attached to
`the lift forces produced by individual wing members of
`the central portion 14 of the fuselage 12. The individual
`equivalent area. To provide further efficiency and oper
`wing members 22 are shaped to provide a highly ef?
`ational stability, the wing members 22 should be ar
`cient lift force and, as shown in FIG. 5, each wing
`ranged such that the resultant hydrodynamic lift force
`member 22 includes a straight leading edge portion 23,
`vector for the wing section 21 passes through the tow
`a curved intermediate portion 24 and a straight trailing
`ing point 9. For the particular wing section 21 shown in
`edge portion 27. The leading edge 23 serves as an “en
`FIG. 4, this is accomplished by separating the upper and
`trance” surface for the water flow that tends to prevent
`lower wing members 22 in a direction perpendicular to
`flow separation between the water and the wing mem
`the longitudinal axis 16 of the fuselage 12 by approxi
`ber 22. The intermediate portion 24 is curved so that the
`mately one-third of the chord distance of the wing
`.?ow along the convex surface 26 is accelerated while
`member 22 wherein the longitudinal separation parallel
`the flow across the concave surface 25 is reduced,
`to longitudinal axis 12 is approximately one chord di
`thereby causing a large pressure differential therebe
`mension of the wing member 22. The lower wing mem
`tween and generating the resultant lift force for the
`ber is tilted with respect to the longitudinal axis 16 of
`wing member 22. The straight trailing edge portion 27
`the fuselage 12 such that the plane de?ned by the trail
`serves to prevent ?ow separation between the water
`ing edge portion 27 of the wing member 22 extends at
`?ow and the wing member 22. The relative dimensions
`an angle of about 24° thereto. Also, the upper wing
`of the leading edge portion 23, the intermediate portion
`member in FIG. 4, is tilted at a relative angle of 6° to the
`24, and the trailing edge portion 27 are such\_that the
`lower wing member and the trailing edge portion 27 of
`resultant lift force vector acting on a given wing mem
`
`30
`
`35
`
`45
`
`50
`
`55
`
`60
`
`65
`
`PGS v. WESTERNGECO (IPR2014-00689)
`WESTERNGECO Exhibit 2058, pg. 6
`
`

`

`20
`
`mized.
`
`,
`
`,
`
`4,463,701
`6
`5
`control ?ap 31, as shown in FIG. 4, causes an ef?cient
`the upper wing member extends at an angle of about 30°
`and rapid depth response for small de?ections of the
`with the longitudinal axis 16 of the fuselage 12. Thus,
`control ?ap 31. In FIG. 4, for example, a de?ection of
`the chord lines of the upper and lower wing members 22
`the control ?ap 31 wherein the trailing edge portion 33
`in FIG. 4, will form oblique angles of 18° and 13°, re
`spectively, with the longitudinal axis 16 of the fuselage
`goes into the drawing would cause a clockwise rotation
`12. Preferably, such oblique angles will be from about
`of the paravane 11, as viewed from the front end of the
`paravane 11 and as depicted by the are 36 in FIG. 4.
`10° to about 24°. A paravane 11 of the foregoing com
`Accordingly, as the paravane 11 begins to roll in such a
`pact, ef?cient design was found to have a lift coef?cient
`clockwise fashion, the vertical-force component devel
`of about 1.5 and a drag coef?cient of about 0.4.
`oped on the wing members 22 causes the paravane 11 to
`End plates 28 as shown in the various ?gures, inter
`connect the wing members 22 and enhance the lift force
`rise in the water. When the paravane 11 reaches a pre
`determined depth, the ?ap 31 returns to the neutral,
`acting on the wing members 22 by preventing pressure
`unde?ected position. A tapered horn member 35 is
`leakage (e.g. water ?ow) around the tips of the wing
`positioned forward of the control ?ap 31 to prevent
`members 22. The end plates 28 also serve as a ballasting
`damage thereto and fouling thereof with cables and
`means wherein one of the end plates 28 may be made
`marine vegetation. For minimizing the torque required
`heavier than the other end plate 28 to cause the wing
`to pivot the control ?ap, it was determined that the
`section 21 to assume a vertical position in the water as
`pivot axis 34 for the control ?ap 31 should be located at
`shown in FIGS. 1 and 2.
`about 33% of the ?ap chord from the leading edge 32 of
`A lateral stabilizer 18, which comprises two equal
`the control flap 31. Thus, by positioning the control flap
`area ?n portions balanced about the longitudinal axis 16
`31 close to the wing section 21 to take advantage' of the
`of the fuselage 12, serves to maintain the fuselage 12
`accelerated flow conditions and having the pivot axis 34
`lined up with the towing direction and to minimize
`of the control flap 31 extend closely adjacent to the tow
`undesirable dynamic motions such as lateral yaw-roll
`point 9, a highly ef?cient depth control is achieved
`coupling. In describing movements of the paravane
`wherein adverse yaw-roll coupling effects are , mini
`about a coordinate system de?ned by a yaw, a rolling
`and a pitching axis, the yaw axis will be defined by a line
`which is both normal to the longitudinal axis 16 of the
`fuselage 12 and the plane generally de?ned by the wing
`members 22. The pitch axis is de?ned by a line which is
`parallel to the plane encompassed by the wing members
`30
`22 and normal to the longitudinal axis 16 of the fuselage
`12. Further, the roll axis is de?ned as being parallel and
`most probably coincident with the longitudinalaxis 16
`of the fuselage 12. A lateral de?ection is de?ned as a
`displacement which occurs within a plane generally
`de?ned by the wing members 22 and a longitudinal
`de?ection will be de?ned as a displacement which oc
`curs in a direction which is perpendicular to the plane
`de?ned by the wing members 22. Thus, the lateral stabi
`lizer tends to reduce movements of the paravane 11
`about the yaw axis and the roll axis as well as minimiz
`ing relative lateral displacements of the tail portion 15
`from the towing direction.
`A longitudinal stabilizer 19 is secured to one of the
`lateral stabilizers, as generally shown in FIGS. 1-3, to
`reduce pitching motions and to minimize lateral dis
`placements of the tail portion 15 of the fuselage 12. The
`longitudinal stabilizer 19 has been located to minimize
`the ?ow interference from the. wing members 22 and
`means are provided for adjusting the position of the
`longitudinal stabilizer 19 to vary the wing lift. This is
`generally accomplished by pivoting the longitudinal
`stabilizer 19 about an axis which extends normal to the
`lateral stabilizer 18 and subsequently securing the stabi
`lizer 19 in a ?xed position.
`The mechanical means for controlling the depth of
`the paravane comprises a control ?ap 31 which is piv
`oted to move about an axis 34 that is perpendicular to
`the wing members 22and parallel to the lateral stabi
`lizer 18. The control ?ap 31 is located relative to the
`wing section 21 and the tow point 9 such that de?ection
`of the control ?ap 31 will impart a high degree of roll
`but a minimal amount of yaw motion. This roll motion
`will thereby cause wing members 22 which are nor
`mally oriented in a vertical direction to tilt from such
`position so that a large vertical force component is
`generated on the wing members 22 to cause the para
`vane 11 to move in a predetermined direction. Thus, the
`
`Means for controlling the position of the control ?ap
`31 and thus the depth of the paravane 11 is generally
`shown in FIG. 6, wherein the basic components include
`low and high range depth gauges; an analog memory
`unit containing an ordered depth parameter; a DC servo
`motor; a roll pendulum potentiometer, hereinafter re
`ferred to as a roll transducer; and other electrical appa
`ratus. Two types of depth gauges 37 are utilized to
`obtain the required accuracy throughout the depth
`range of the paravane, wherein the depth gauges (of the
`pressure transducer type) 37 are positioned in the fuse
`lage 12 so that the dynamic pressure-due to the ?ow of
`water is at a minimum or zero. To protect the low pres
`sure gauge at great depths, a blanking valve can be built
`into the pressure gauges. The depth measured by the
`pressure gauge or transducer 37, such as model Z-625
`made by Sencotec, is converted into an electrical volt
`age (Zm) which is proportional to the measured depth.
`The analog memory unit 38, such as unipolar unit
`EUWAOC made by Natsushita Ltd. of Osaka, Japan, is
`used to establish an ordered depth voltage (20). The
`reference or ordered depth voltage (Z0) is applied to
`the analog memory unit 38 through a separate calibra
`tion module and when the module is unplugged from
`the paravane 11, the reference voltage (Z0) is retained
`in the analog memory unit 38. Thereafter, when the
`paravane _11.,is operating, the measured depth (Zm) and
`ordered depth (Z0) values are constantly being com
`pared in arsumming' device 39. The error value or the
`voltage difference between Zm and Z0 is then amplified
`bythegain ampli?er 40, such as Operational Ampli?er
`MC-3403 made by Motorola, Inc.
`Thereafter, the amplified voltage M(Zo—-Zm) is ap
`plied ,to an analog switch 41, such as Quad Analog Gate
`l H 5009 manufactured by Intersil, a division of Date],
`Inc. The analog switch 41 functions as an override
`switch so that if the wing members 22 roll more than
`45°, for example, from a vertical position, as measured
`by the roll transducer 42, the roll override unit 47 sends
`an appropriate signal to the analog switch 41 such that
`the signal M(Zo-Zm) from the gain ampli?er 40 is
`blocked and van appropriate signal from the analog
`
`40
`
`45
`
`55
`
`60
`
`65
`
`PGS v. WESTERNGECO (IPR2014-00689)
`WESTERNGECO Exhibit 2058, pg. 7
`
`

`

`result.
`
`_
`
`I
`
`10
`
`30
`
`35
`
`4,463,701
`8
`7
`portions of said wing members lie within a plane which
`switch 41 is sent to a second summing device 46 such
`forms an oblique angle with said longitudinal axis of
`that the control ?ap :31 is returned to a neutral position.
`The oil damped roll transducer 42, such as model CT
`said fuselage. ‘
`6. The apparatus according to claim 5, wherein said
`17,1303-3 made by Humphrey, Inc., and associated roll
`oblique angle is between about 20° and 33°.
`override circuitry 47 is employed to ‘prevent the para
`7. The apparatus according to claim 2, wherein said
`vane ll'from rolling completely over when the control
`trailing edge portions of adjacent wing members lie
`?ap 31 is de?ected. For example, when the paravane 11
`within planes which de?ne angles therebetween of from
`is initially deployed, the large difference in the values
`about 4'‘ to about 10°.
`20, Zm would ordinarily cause a large de?ection of the
`8. The apparatus according to claim 1, wherein said
`control ‘?ap 31 and result in large rolling moments. If
`fuselage has a longitudinal axis and each wing member
`uncontrolled, the paravane 11 would continue to roll
`is longitudinally offset from the adjacent wing member
`over, as in a tailspin, and eventual fouling of the para
`by the chord length of a selected wing member.
`vane 11 in the towing cables 8 or damage thereto may
`9. The apparatus according to claim 1, wherein said
`fuselage has a longitudinal axis and each said wing
`member is separated in a direction perpendicular to the
`longitudinal axis of the fuselage by approximately one
`third of the chord distance of the wing member and
`wherein the longitudinal separation parallel to longitu
`dinal axis is approximately one chord dimension of the
`wing member.
`10. The apparatus according to claim 1, wherein:
`said stability means comprises a lateral stabilizer ?n
`secured to the tail end portion of said fuselage and
`extending generally normal to said wing section for
`maintaining said fuselage lined up with the towing
`direction; and
`a longitudinal stabilizer ?n connected to said lateral
`stabilizer and extending generally normal thereto,
`said stabilizer ?n being adjustable to vary the resul
`tant hydrodynamic lift force vector on said wing
`section.‘
`11. The apparatus according to claim 1, further com
`prising:
`a towing mount attached to said fuselage for receiv
`ing a towing cable; and
`said depth control ?ap has a pivot axis which extends
`closely adjacent to said towing mount for minimiz
`ing yaw-roll coupling motions when said control
`?ap is pivoted from a neutral position.
`12. A towed underwater apparatus comprises:
`an elongated fuselage portion;
`a wing section of elongated spaced wing members
`attached to the intermediate portion of the fuse
`lage;
`a depth control ?ap positioned adjacent to the wing
`section and pivotally connected to the intermediate
`portion of the fuselage;
`a tow mount forreceiving a towing cable is secured
`to the intermediate portion of the fuselage adjacent
`to the wing section, on the opposite side of the
`fuselage from the depth control flap, and generally
`opposite to the depth control ?ap;
`stability means attached to the fuselage for maintain
`ing the fuselage lined up with the direction of tow;
`and
`a depth control means located within the fuselage and
`connected to the control flap, the depth control
`means is operable in response to hydrostatic pres
`sure for controlling the position of the control ?ap.
`13. A towed underwater apparatus comprises:
`an elongated fuselage portion;
`a wing section of elongated spaced wing members
`attached to the fuselage, each wing member in
`cludes a convex surface and means to reduce ?uid
`?ow separation adjacent the wing members;
`stability means attached to the fuselage for maintain
`ing the fuselage lined up with the direction of tow;
`
`If the roll override logic in the analog switch 41 has
`not been activated, the value M(Zo—Zm) from the gain
`ampli?er 40 is sent through the analog switch 41 to a
`second summing device 43 wherein a ?n position feed
`back value (FBK) is added therewith. The ?n position
`indicator 46 functions essentially as a potentiometer
`where a deflection of the control ?ap 31 in one direction
`is accompanied by a negative FBK value and a de?ec
`tion of the control flap 31 in the other direction is re
`?ected in a positive FBK value. The second summing
`device 43 sends the resultant signal (DF) to a servo
`25
`ampli?er 44 and the DC servo motor 45. The second
`summing device 43, servo ampli?er 44, servo motor 45
`and ?n position indicator 46 are arranged to rotate the
`control ?ap 31 until the value of DF is zero, wherein
`DF=M(Zo—Zm)-FBK.
`Obviously many modi?cations and variations of the
`present invention are possible in light of the above
`teachings. It is therefore to be understood that within
`the scope of the following claims the invention may be
`practiced otherwise than as speci?cally described.
`What is claimed is:
`t
`-
`1. A towed underwater apparatus comprises:
`an elongated fuselage portion;
`a wing section of elongated spaced wing members
`attached to the fuselage, each wing member in
`40
`cludes a convex surface and'means to reduce ?uid
`?ow separation adjacent the wing members;
`stability means attached to the fuselage for maintain
`ing the fuselage lined up with the direction of tow;
`45
`a depth control ?ap positioned adjacent to the wing
`section and pivotally connected to the-fuselage so
`that the leading edge of the ?ap is disposed beneath
`and closely adjacent to the leading edge of the
`wing section; and
`a
`r
`‘
`’-'
`a depth control means located within the fuselage and
`connected to the control ?ap, the depth control
`means is operable in response to the hydrostatic
`pressure for controlling the position of the control
`?ap.
`'
`2. The apparatus according to claim 1, wherein each
`said wing member includes a straight leading edge por
`tion, a straight trailing edge portion and a curved inter
`mediate portion.’
`_
`i
`3. The apparatus according to claim 2, wherein the
`ratio of the length of said trailing edge portion to said
`leading edge portion is 10:1.
`4. The apparatus according to claim 2, further com
`prising end plates interconnecting the end portions of
`said wing members remote from said fuselage and said
`end plates extending generally parallel with said fuse
`lage.
`‘
`5. The apparatus according to claim 2, wherein said
`fuselage has a longitudinal axis and said trailing edge
`
`55
`
`65
`
`PGS v. WESTERNGECO (IPR2014-00689)
`WESTERNGECO Exhibit 2058, pg. 8
`
`

`

`4,463,701
`10
`a depth control ?ap pivotally connected to the fuse
`sure for controlling the position of the control flap,
`lage;
`the depth control means includes a roll override
`a tow mount attached to the fuselage for receiving a
`means responsive to a predetermined amount of tilt
`towing cable, the tow mount is located so that the
`of the wing section from a vertical position during
`resultant hydrodynamic lift force vector acting on
`towing operation to return the control flap to a
`the wing section during towing operations is lined
`neutral, unde?ected position wherein the control
`up with the tow mount; and
`?ap lies in a plane which is generally parallel with
`a depth control means located within the fuselage and
`the longitudinal axis.
`connected to the control ?ap, the depth control
`15. A towed underwater apparatus comprises:
`means is operable in response to hydrostatic pres
`an elongated fuselage;
`sure for controlling the position of the control ?ap.
`a wing section of spaced wing members attached to
`14. A towed underwater apparatus comprises:
`the fuselage, each wing member includes a straight
`an elongated fuselage portion having a longitudinal
`leading edge portion, a straight trailing edge por
`axis;
`tion, and a curved intermediate portion, wherein
`a wing section of elongated spaced wing members
`the ratio of the length of said trailing edge portion
`attached to the fuselage, each wing member in
`to said leading edge portion is about 10:1;
`cludes a convex surface portion and means to re
`a depth control flap pivotally connected to the fuse
`duce ?uid ?ow separation adjacent the wing mem
`lage and located adjacent the wing section;
`bers;
`stability means attached to the fuselage for maintain
`stability means attached to the fuselage for maintain
`ing the fuselage li