US3800727A - Automatic landing system for hydrofoil craft - Google Patents

Automatic landing system for hydrofoil craft Download PDF

Info

Publication number
US3800727A
US3800727A US00312483A US3800727DA US3800727A US 3800727 A US3800727 A US 3800727A US 00312483 A US00312483 A US 00312483A US 3800727D A US3800727D A US 3800727DA US 3800727 A US3800727 A US 3800727A
Authority
US
United States
Prior art keywords
craft
primary
hydrofoil
source
borne
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00312483A
Other languages
English (en)
Inventor
D Stark
I Hirsch
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Boeing Co
Original Assignee
Boeing Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Boeing Co filed Critical Boeing Co
Application granted granted Critical
Publication of US3800727A publication Critical patent/US3800727A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B63—SHIPS OR OTHER WATERBORNE VESSELS; RELATED EQUIPMENT
    • B63B—SHIPS OR OTHER WATERBORNE VESSELS; EQUIPMENT FOR SHIPPING 
    • B63B1/00—Hydrodynamic or hydrostatic features of hulls or of hydrofoils
    • B63B1/16—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving additional lift from hydrodynamic forces
    • B63B1/24—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving additional lift from hydrodynamic forces of hydrofoil type
    • B63B1/28—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving additional lift from hydrodynamic forces of hydrofoil type with movable hydrofoils
    • B63B1/30—Hydrodynamic or hydrostatic features of hulls or of hydrofoils deriving additional lift from hydrodynamic forces of hydrofoil type with movable hydrofoils retracting or folding

Definitions

  • ABSTRACT A control system for a hydrofoil characterized in that a transition from the foil-borne to the hull-borne mode of operation is initiated and the craft caused to descend or land automatically before an unsafe foilborne roll or yaw attitude can be developed. This is achieved by providing an auxiliary electronic power source and auxiliary servo feedbacks in parallel with the main feedbacks for the control surface servos of the hydrofoil.
  • the auxiliary feedbacks provide means.
  • SHEET 2 BF 3 78 FORWARD M INTEGRAL ACCELEROMETER AMPLIFIER l I I8 I6 98 FWD ROLL INVERT FLAP D SQUARED SERVO F -1 I PITCH 86 PITCH I DERIVATIVE I AMPLIFIER PORT 26 vE TIcAL 44 80 H6 FLAP GYRO I I SERVO -13 ouT- 2 ll4" ROLL BOARD 32 RoLL i DAER'LVAHEE M LI R L J "2 9O INVERT I STBD 26 42 V FLAP SERVO PORT OUT VERTICAL BOARD 28 AccELERoMETER 84 40 I 7e PORT 26 STBD FLAP vERTIcAL SERVO ACCELEROMETER INBOARD 94 YAW RATE 1 Egg?
  • the flaps are used primarily to cause the craft to ascend or descend and to control the craft about its pitch and roll axes; however they can also be used in combination with the rudder to bank the ship about its roll axis during a turn.
  • the flaps are also used to stabilize the craft during movement on water. For example, pitching or rolling motions can be minimized by proper counterbalancing movement of the flaps.
  • a system for automatically initiating a transition from the foil-borne to the hull-bome mode of operation of a hydrofoil craft upon the occurrence of a power failure or other ofi'-normal condition and before an unsafe foil-borne roll or yaw attitude can be developed.
  • the invention provides for two separate servo systems for controlling the rudder and each of the flaps on the foils or control surfaces of a hydrofoil craft.
  • One servo system for each control surface is powered by the main power supply for the craft, usually an alternating current power source; while the other system is powered by a separate source, usually batteries providing direct current.
  • the main power supply for the craft usually an alternating current power source
  • a separate source usually batteries providing direct current.
  • both the alternating current servo system and the alternate direct current-powered servo system are employed.
  • control of the control surface positions is dominated by the alternating current system which causes the control surfaces to position in response to commands from the pilothouse as well as motion sensing devices.
  • the direct current auxiliary servo system which provides a small control command at all times, takes over and causes the control surfaces to move to predetermined positions which will force the craft to land rapidly and safely.
  • the auxiliary feedback null positions for the automatic landing Hence, no landing commands are necessary.
  • FIG. 1 is a side view of a typical hydrofoil craft with which the control system of the invention can be used;
  • F IG. 2 is a bottom view of the craft shown in FIG. 1;
  • FIG. 3 is a block schematic diagram showing in general outline the normal control system for the craft.
  • FIG. 4 shows in detail the dual servo systems of the invention for the control surfaces on the hydrofoil.
  • the hydrofoil shown includes a conventional hull 10 which can be provided with a propeller or the like and an inboard motor, not shown, in order that it can traverse the surface of water as a conventional displacement ship.
  • a forward, swiveled strut or rudder 12 Pivotally connected to the hull is a forward, swiveled strut or rudder 12 which is rotatable about a vertical axis in order to steer the craft in the foil-borne mode of operation.
  • the rudder 12 can also be swiveled upwardly in the direction of arrow 14 to clear the surface of the water when the craft is operating as a conventional displacement ship.
  • Carried on the lower end of the rudder 12 is a forward foil 16 (FIG.
  • the forward foil can be rotated for control.
  • there is a single forward control be it flap or incidence (i.e., foward foil) means.
  • struts 20 and 22 are pivotally connected to the hull 10 about an axis 21.
  • the struts 20 and 22 can be rotated downwardly into the solid-line position shown in FIG. 1 for foil-borne operation, or can be rotated backwardly in the direction of arrow 24 and into the dotted-line position shown when the craft operates as a conventional displacement ship.
  • Extending between the lower ends of the struts 20 and 22 is an aft foil 26 which carries, at its trailing edge, two starboard flaps 28 and 30 and two port flaps 32 and 34.
  • the starboard and port foils can be rotated themselves.
  • each set of starboard flaps and each set of port flaps normally operates in synchronism.
  • a gas turbinewater jet propulsion system 33 Carried between the struts 20 and 22 and pivotally connected to the hull about axis 21 is a gas turbinewater jet propulsion system 33 which provides the forward thrust for the craft during foil-borne operation. It should be understood, however, that a propeller or other type of thrust-producing device can be used in accordance with the invention.
  • both the rudder 12 and its foil 16, and struts 20 and 22 with foil 26 are rotated downwardly into the solid-line positions shown in FIG. 1 and locked in position.
  • the pilot sets the desired foil depth in a manner hereinafter described and the throttles are advanced. The craft, therefore, will accelerate and the hull will clear the water and continue to rise until it stabilizes at the commanded foil depth.
  • the normal landing procedure is to simply reduce the throttle setting, allowing the ship to settle to the hull as the speed decays.
  • a height sensor 36 which produces an electrical signal proportional to the height of the bow above the surface of the water during foil-borne operation.
  • a forward vertical accelerometer which produces an electrical signal proportional to vertical acceleration.
  • a lateral accelerometer 38 which, of course, produces an electrical signal proportional to lateral or sideways acceleration of the craft during turning.
  • Mounted on the top of the starboard strut 20 is an aft starboard vertical accelerometer 40; and mounted at the top of the port strut 22 is an aft port vertical accelerometer 42.
  • a vertical gyro 44 is mounted in the craft, preferably near the center of gravity, for producing signals proportional to the angle of the craft with respect to vertical about its pitch and roll axes.
  • a yaw rate gyro is provided in the forward portion of the craft. The accelerometers and the gyros will sense motions of the craft about its roll, pitch and yaw axes.
  • any movement about the roll axis will be sensed by the vertical gyro 44 as well as the aft accelerometers 40 and 42.
  • the gyro 44 will produce an output signal proportional to the amount or degree of roll; while the accelerometers 40 and 42 will produce signals proportional to 'the rate of change in position about the roll axis.
  • Any movement about the pitch axis will be sensed by the vertical gyro 44 as well as both the forward and aft accelerometers 35, 40 and 42.
  • any movement about the yaw (i.e., vertical) axis will be sensed by the yaw rate gyro 45 as well as the lateral accelerometer 38.
  • the height of the hull above the water is controlled solely by the forward flap 18.
  • the forward flap In order to raise the hull from the surface of the water, the forward flap is rotated downwardly, thereby increasing the lift afforded by the forward foil 16 and causing the hull to elevate out of the water.
  • both the forward and aft flaps are employed. However, the forward and aft flaps operate in opposite directions to correct any pitch condition.
  • the forward flap 18 will be rotated downwardly; while the aft flaps 28-32 will be rotated upwardly to produce a moment counterbalancing that pitching moment caused by waves or the like. Compensation for movement about the roll axis is achieved solely by the aft flaps 28-32; however in this case the starboard flaps move in a direction opposite to the port flaps to correct for any undesired rolling motion.
  • the aft flaps are initially positioned to cause the craft to bank about its roll axis; whereupon the rudder 12 is rotated to follow through. This gives a much better and smoother turning action since the correct roll inclination is achieved before any substantial turning of the craft occurs via the rudder.
  • hydrofoil shown herein and the control system about to be described is the subject matter of the aforesaid copending application Ser. No. 302,559, filed Oct. 31, 1972 and assigned to the Assignee of the present application.
  • the invention can be used with any hydrofoil control system, the essential feature being the inclusion of secondary servo systems for the control surfaces of the craft which cause it to land or descend onto the water automatically upon the occurrence of a failure of the normal alternating current power supply for the control system.
  • the signal from the height sensor 36 proportional to actual height is compared with the desired height signal from the pilothouse depth control 68 on lead 66 in a depth error amplifier 74.
  • a signal on leadderived from the helm 72 and proportional to helm position is applied to a roll derivative amplifier 80 where it is compared with a signal on lead 82 from vertical gyro 44 proportional to the roll angle about the yaw axis relative to vertical.
  • the signal on lead 82 will be zero, or substantially zero.
  • the roll derivative amplifier compares the signal on lead 82 with that on lead 70; and assuming that the two are not the same, as is the case for the conditions just described, then an output signal appears at the output of the amplifier 80 and is applied to inboard and outboard port flap servos 84 and 86. At the same time, it is applied in an inverted form to the inboard and outboard starboard flap servos 88 and 90.
  • the result is that one set of aft flaps will rotate downwardly while the other set rotates upwardly to cause the craft to bank about its roll axis. This action will continue until the angle of roll as sensed by the gyro 44 is such as to generate a signal which nulls out the helm signal on lead 70.
  • the signal on lead 82 is also applied to a rudder servo 92.
  • the craft banks to the right in response to a signal from helm 72,' the rudder 12 will thereafter rotate to steer the craft to the right. This gives a much smoother turn for all sea conditions encountered with a minimum of acceleration forces on the passengers and crew.
  • the yaw rate gyro 45 will produce a signal on lead 94 proportional to the rate of turning about the yaw axis; and this is utilized in the rudder servo 92 to limit the rate of turning.
  • the forward lateral accelerometer 38 which produces a signal on lead 96 proportional to lateral acceleration.
  • the signal on lead 70 decreases back to zero; whereupon the positions of the aft flaps are reversed to cause the craft to come back up into a vertical position about the roll axis.
  • the output of the vertical gyro 44 on lead 82 decreases to zero, the rudder 12 is centered, and the craft is again stabilized.
  • the forward accelerometer 35 senses acceleration, either upward or downward, at the bow and produces an electrical signal for controlling the forward flap 18 to counteract movement about the pitch axis 62.
  • the output of the forward accelerometer 35 is combined in integral amplifier 100 with a signal proportional to the roll signal squared as derived from circuit 98 before the combined signal is applied to the forward flap servo 78. This is for the reason that during a turn and while the craft is being banked about its roll axis, and during normal rolling action in heavy seas, the rolling movement produces a component of vertical acceleration which must be taken into consideration.
  • a signal proportional to the angle of the craft about the pitch axis is derived from vertical gyro 44 on lead 102. This is applied to a pitch derivative amplifier 104 which produces an output signal which varies as a function of pitch angle from horizontal and the rate of change of pitch angle. The output of the pitch derivative amplifier 104 is then applied to all of the aft flap servos and is also applied in an inverted form to the forward flap servo 78 to achieve differential control. This signal is used for stability augmentation, ride smoothing in a seaway, and automatic pitch trim control.
  • a signal will be derived on lead 82 which is again applied to the roll derivative amplifier 80.
  • the signalon lead 82 under these circumstances will first increase in one direction or polarity, then recede back to zero and increase in the other direction or other polarity and again recede back to zero as the craft rolls from side-toside.
  • This again produces at the output of the roll derivative amplifier a signal which varies as a function of both the roll angle as well as the rate of change of roll angle.
  • the signal is applied to the aft port and starboard servos so as to achieve differential action that counteracts the rolling movement.
  • a signal of one polarity is applied to the port flap servo; while a signal of inverted polarity is applied to the starboard fiap servo to achieve rotation of the respective port and starboard flaps in opposite directions to counteract a rolling motion.
  • the output of the port vertical accelerometer 42 is applied to both the inboard and outboard port flap servos 84 and 86 and acts to vary the aft port flap position to counteract any vertical acceleration or heave on the port side.
  • the output of the starboard vertical accelerometer 40 is applied to both the inboard and outboard starboard flap servos 88 and 90 to achieve the same action and counteract vertical accelerations on the starboard side of the craft.
  • the outboard port flap servo is shown in FIG. 4. It includes a port flap servo amplifier which, in effect, comprises an operational amplifier having four summed inputs applied to one of its two input terminals through resistors.
  • the four inputs to the operational amplifier 110 include signals on leads l12ll8.
  • the signal on lead 112 is that from the pitch derivative amplifier 104; the signal on lead 114 is that from the roll derivative amplifier 80; and the signal on lead 116 is that from the port vertical accelerometer 42.
  • the signal on lead 118 is a feedback signal proportional to actual flap position. That is, a forward flap actuator 120 is connected through a mechanical linkage 122 to the outboard port flap 32. This same mechanical linkage 122 is connected to a primary position transducer 124 which produces a signal whose magnitude varies as a function of the angular position of the flap 32 and whose polarity depends upon whether the flap is rotated upwardly or downwardly from its central or null position. This signal is applied through a feedback demodulator 128 and a scaling network 130 to lead 118 and, hence, to the input of the servo amplifier 110.
  • the arrangement comprises a conventional servo system wherein an output signal from the servo amplifier 110 will actuate the port flap valve 119 and the port flap actuator 120 to vary the position of flap 32.
  • a feedback signal is generated at the output of network 124; and this signal persists until it nulls out or cancels the combined input signals on the other input leads 112-116 which initiated the control action.
  • the primary position transducer 124 as well as all of the circuitry thus far described is powered by means of an alternating current power source identified by the reference numeral 139.
  • This power source also supplies power to all other servos. If this source should fail for some reason or other, and assuming that the auxiliary servo control of the invention is not utilized, there will be no control over the various control surfaces or flaps and they will drift to their stops due to the integrating action of the actuators and servo valves; the craft will be out of control; and a dangerous and unsafe roll or yaw attitude can be developed before the pilot manually responds and cuts back the throttles to land the craft.
  • a second servo feedback includes a secondary position transducer 132 connected to the port flap actuator 120 and linkage 122 such that the output of the secondary transducer will be a signal proportional to actual flap position from some preset condition, which preset condition is that necessary to cause the craft to land.
  • control system for a hydrofoil craft of the type having at least one control surface, electrical circuit means including a primary servo system for controlling said surface during normal operation of the hydrofoil, and a primary source of electrical power for said electrical circuit means, the combination of:
  • auxiliary electrical circuit means including a secondary servo feedback system preset to automatically vary the position of said surface to cause said hydrofoil craft to descend from a foil-borne to a hullbome mode of operation upon the occurrence of a failure in said primary power source, and I a secondary source of electrical power for said auxiliary electrical circuit means separate and apart from said primary power source.
  • said primary source of electrical power comprises a source of alternating current power
  • said secondary source of power comprises a direct current power source
  • hydrofoil craft includes a plurality of foils and a plurality of control surfaces each provided with a primary servo system and a secondary servo system.
  • electrical circuit means including a primary servo system for controlling said surfaces during normal operation of the hydrofoil, and a primary source of electrical power for said electrical circuit means, the combination of:
  • auxiliary electrical circuit means including a secondary servo feedback system preset to automatically rotate said forward control surface upwardly and said aft control surface downwardly to cause said hydrofoil craft to descend from a foil-borne to a hull-borne mode of operation upon the occurrence of a failure in said primary power source, and
  • auxiliary electrical circuit means separate and apart from said primary power source.

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Ocean & Marine Engineering (AREA)
  • Engineering & Computer Science (AREA)
  • Combustion & Propulsion (AREA)
  • Mechanical Engineering (AREA)
  • Chemical & Material Sciences (AREA)
  • Control Of Position, Course, Altitude, Or Attitude Of Moving Bodies (AREA)
  • Manufacture Of Alloys Or Alloy Compounds (AREA)
  • Nonmetallic Welding Materials (AREA)
  • Superconductors And Manufacturing Methods Therefor (AREA)
  • Adjustment And Processing Of Grains (AREA)
  • Safety Devices In Control Systems (AREA)
US00312483A 1972-12-06 1972-12-06 Automatic landing system for hydrofoil craft Expired - Lifetime US3800727A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US31248372A 1972-12-06 1972-12-06

Publications (1)

Publication Number Publication Date
US3800727A true US3800727A (en) 1974-04-02

Family

ID=23211681

Family Applications (1)

Application Number Title Priority Date Filing Date
US00312483A Expired - Lifetime US3800727A (en) 1972-12-06 1972-12-06 Automatic landing system for hydrofoil craft

Country Status (17)

Country Link
US (1) US3800727A (xx)
JP (1) JPS5649798B2 (xx)
AU (1) AU477273B2 (xx)
BE (1) BE800351A (xx)
BR (1) BR7309535D0 (xx)
CA (1) CA969038A (xx)
CH (1) CH574840A5 (xx)
DE (1) DE2337993C3 (xx)
DK (1) DK303573A (xx)
ES (1) ES415402A1 (xx)
FR (1) FR2210303A5 (xx)
GB (1) GB1386913A (xx)
IT (1) IT985142B (xx)
NL (1) NL164814C (xx)
NO (1) NO138837C (xx)
SE (1) SE381232B (xx)
ZA (1) ZA739040B (xx)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3899987A (en) * 1974-04-10 1975-08-19 Boeing Co Fail-safe control system for hydrofoil craft
US4159690A (en) * 1977-12-07 1979-07-03 The Boeing Company Automatic landing system for hydrofoil craft
US4178871A (en) * 1974-01-23 1979-12-18 The Boeing Company Automatic control system for hydrofoil craft
US5558034A (en) * 1994-07-06 1996-09-24 Hodapp; Gary Lift transportable with pontoon boats or the like
EP0800989A1 (en) * 1996-03-29 1997-10-15 Chung Chen Clifford Shaw Hybrid high performance water vessels
US6948441B2 (en) 2003-02-10 2005-09-27 Levine Gerald A Shock limited hydrofoil system
US20060070565A1 (en) * 2003-02-10 2006-04-06 Levine Gerald A Shock limited hydrofoil system
US20090235857A1 (en) * 2008-03-19 2009-09-24 Hodapp Gary D Onboard Boat Lift Structure And Method
US20110232559A1 (en) * 2008-03-19 2011-09-29 Hewitt Machine & Manufacturing, Inc. Boat Lift Attachment With Side Mount Actuators
CN105775065A (zh) * 2016-05-07 2016-07-20 广州中国科学院工业技术研究院 一种船舶减摇的方法及其装置

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO1983001934A1 (en) * 1981-11-30 1983-06-09 Donald George Daw Steering vessels
JPH0215829Y2 (xx) * 1985-12-26 1990-04-27

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3049623A (en) * 1961-03-30 1962-08-14 W W Henry Company Auxiliary power supply
US3137260A (en) * 1962-04-03 1964-06-16 Sperry Rand Corp Control system
US3405337A (en) * 1965-04-13 1968-10-08 Sperry Rand Corp Fail operational control system for redundant servos with torque signal equalization

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3049623A (en) * 1961-03-30 1962-08-14 W W Henry Company Auxiliary power supply
US3137260A (en) * 1962-04-03 1964-06-16 Sperry Rand Corp Control system
US3405337A (en) * 1965-04-13 1968-10-08 Sperry Rand Corp Fail operational control system for redundant servos with torque signal equalization

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4178871A (en) * 1974-01-23 1979-12-18 The Boeing Company Automatic control system for hydrofoil craft
US3899987A (en) * 1974-04-10 1975-08-19 Boeing Co Fail-safe control system for hydrofoil craft
JPS50136886A (xx) * 1974-04-10 1975-10-30
JPS568788B2 (xx) * 1974-04-10 1981-02-25
US4159690A (en) * 1977-12-07 1979-07-03 The Boeing Company Automatic landing system for hydrofoil craft
US5558034A (en) * 1994-07-06 1996-09-24 Hodapp; Gary Lift transportable with pontoon boats or the like
EP0800989A1 (en) * 1996-03-29 1997-10-15 Chung Chen Clifford Shaw Hybrid high performance water vessels
US6948441B2 (en) 2003-02-10 2005-09-27 Levine Gerald A Shock limited hydrofoil system
US20060070565A1 (en) * 2003-02-10 2006-04-06 Levine Gerald A Shock limited hydrofoil system
US7182036B2 (en) 2003-02-10 2007-02-27 Levine Gerald A Shock limited hydrofoil system
US20090235857A1 (en) * 2008-03-19 2009-09-24 Hodapp Gary D Onboard Boat Lift Structure And Method
US20110232559A1 (en) * 2008-03-19 2011-09-29 Hewitt Machine & Manufacturing, Inc. Boat Lift Attachment With Side Mount Actuators
US9950772B2 (en) 2008-03-19 2018-04-24 Hewitt Machine & MFG, Inc. Onboard boat lift structure and method
US10308322B2 (en) 2008-03-19 2019-06-04 Hewitt Machine & Mfg., Inc. Onboard boat lift with actuator in hollow tube
CN105775065A (zh) * 2016-05-07 2016-07-20 广州中国科学院工业技术研究院 一种船舶减摇的方法及其装置

Also Published As

Publication number Publication date
DK303573A (xx) 1975-01-20
ZA739040B (en) 1974-10-30
CH574840A5 (xx) 1976-04-30
DE2337993C3 (de) 1978-11-30
DE2337993B2 (de) 1978-01-19
NO138837B (no) 1978-08-14
JPS5649798B2 (xx) 1981-11-25
DE2337993A1 (de) 1974-06-12
NL164814B (nl) 1980-09-15
BR7309535D0 (pt) 1974-08-29
CA969038A (en) 1975-06-10
BE800351A (fr) 1973-11-30
JPS4987094A (xx) 1974-08-20
FR2210303A5 (xx) 1974-07-05
NO138837C (no) 1978-11-22
NL164814C (nl) 1981-02-16
AU477273B2 (en) 1976-10-21
GB1386913A (en) 1975-03-12
AU6299073A (en) 1975-05-29
SE381232B (sv) 1975-12-01
ES415402A1 (es) 1976-05-01
IT985142B (it) 1974-11-30
NL7307770A (xx) 1974-06-10

Similar Documents

Publication Publication Date Title
US3886884A (en) Control system for hydrofoil
US3156209A (en) Autopilot for hydrofoil craft
US3800727A (en) Automatic landing system for hydrofoil craft
US4178871A (en) Automatic control system for hydrofoil craft
US4926773A (en) High performance sea-going craft
US4100876A (en) Hydrofoil fixed strut steering control
US2980047A (en) Submarine vessel equipped with hydrofoil assembly
WO2020176033A1 (en) A hydrofoil system
US2749871A (en) Flap depth control for hydrofoil craft
JPH0354091A (ja) 水中翼船の重心位置最適化装置
US4159690A (en) Automatic landing system for hydrofoil craft
US4562546A (en) Stability augmentation system for a forward swept wing aircraft
US3137260A (en) Control system
US3899987A (en) Fail-safe control system for hydrofoil craft
US4926778A (en) Aerodynamic stabilization system for watercraft
JPS62255295A (ja) 水中翼船
US3191567A (en) Control for hydrofoil craft
US3870253A (en) Aircraft vectored flight control means
US4182256A (en) Automatic takeoff controller for hydrofoil craft
US3742890A (en) Free trailing forward hydrofoil strut
US3958522A (en) Automatic control system for hydrofoil craft
US3819135A (en) System for augmenting aircraft attitude stability using vertical vane type sensors
US4524710A (en) Automatic trim system for hydrofoil craft
US3548776A (en) Canted rudders for ses
US3168067A (en) Surface watercraft