CA1234417A - System for alerting a pilot of a dangerous flight profile during low level maneuvering - Google Patents
System for alerting a pilot of a dangerous flight profile during low level maneuveringInfo
- Publication number
- CA1234417A CA1234417A CA000449619A CA449619A CA1234417A CA 1234417 A CA1234417 A CA 1234417A CA 000449619 A CA000449619 A CA 000449619A CA 449619 A CA449619 A CA 449619A CA 1234417 A CA1234417 A CA 1234417A
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- Prior art keywords
- altitude
- aircraft
- warning
- recited
- providing
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01C—MEASURING DISTANCES, LEVELS OR BEARINGS; SURVEYING; NAVIGATION; GYROSCOPIC INSTRUMENTS; PHOTOGRAMMETRY OR VIDEOGRAMMETRY
- G01C5/00—Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
- G01C5/005—Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels altimeters for aircraft
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P1/00—Details of instruments
- G01P1/07—Indicating devices, e.g. for remote indication
- G01P1/08—Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers
- G01P1/10—Arrangements of scales, pointers, lamps or acoustic indicators, e.g. in automobile speedometers for indicating predetermined speeds
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Radar, Positioning & Navigation (AREA)
- Remote Sensing (AREA)
- Emergency Alarm Devices (AREA)
- Radar Systems Or Details Thereof (AREA)
- Traffic Control Systems (AREA)
- Navigation (AREA)
- Alarm Systems (AREA)
Abstract
SYSTEM FOR ALERTING A PILOT OF A
DANGEROUS FLIGHT PROFILE DURING LOW LEVEL MANEUVERING
Abstract of the Disclosure A system that warns the pilot of an aircraft performing low level maneuvers of a dangerous flight profile monitors the altitude of the aircraft above ground, and provides a first specific warning to the pilot if the altitude of the aircraft drops below a predetermined minimum altitude above ground. The system further monitors the roll angle and descent rate of the aircraft to provide a second specific warning if the descent rate of the aircraft exceeds a predetermined rate determined by the roll angle of the aircraft if the aircraft is below a second pre-determined altitude above ground.
DANGEROUS FLIGHT PROFILE DURING LOW LEVEL MANEUVERING
Abstract of the Disclosure A system that warns the pilot of an aircraft performing low level maneuvers of a dangerous flight profile monitors the altitude of the aircraft above ground, and provides a first specific warning to the pilot if the altitude of the aircraft drops below a predetermined minimum altitude above ground. The system further monitors the roll angle and descent rate of the aircraft to provide a second specific warning if the descent rate of the aircraft exceeds a predetermined rate determined by the roll angle of the aircraft if the aircraft is below a second pre-determined altitude above ground.
Description
I
BACKGROUND OF THE INVENTION
Field of the Invention This invention relates generally to ground proximity warning systems, and more particularly to a system that protects an aircraft during low altitude maneuvers if the aircraft should descend below a pro-determined minimum altitude above grounder if the aircraft exceeds a predetermined descent rate while performing turning maneuvers or other maneuvers requiring a roll. Distinct specific warnings are given in order to inform the pilot of the specific action what must be taken to recover from a dangerous flight profile.
Description of the Prior Art Ground proximity warning systems that warn a pilot of a dangerous flight profile are known These systems provide warnings to the pilot of an aircraft under various unsafe flying conditions including flying below a preset minimum altitude, and permitting the aircraft to attain an excessive descent rate after take-off or on approach . An example of a system that provides a pilot with a warning if he drops below a predetermined minimum desired altitude is a system that compares the radio altitude with the minimum decision altitude setting, or "bug" setting on the radio altimeter, and provides an aural or visual warning if the radio altitude dross beloli the set minimum decision altitude. Examples of systems that provide a warning to a pilot during a takeoff or a missed approach phase of ~Z3~ 7 operation if the aircraft should descend at an excessive barometric rate or lose a predetermined amount of barometric altitude are disclosed in United States patent Nos. 3,946,358; 3,947,~08, 3,947,810 and 4,319,218, assigned to the same assignee as the present invention.
While these systems serve to provide the pilot with a warning in the event that the aircraft drops below a preset minimum desired altitude above ground, or if the aircraft descends excessively after take-off or a missed approach, such systems are designed primarily for transport aircraft that do not normally fly at low altitudes or execute turns or other severe or violent maneuvers Lear the ground. Conseauentl~, such systems would not normally provide adequate warn-in to the pilot of a highly maneuverable aircraft such as, for example, a fighter/attack aircraft execute in tactical maneuvers near the ground.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a warning system that overcomes many of the disadvantages of the prior art warning systems during high speed, low level maneuvering phases of aircraft operation.
It is another object of the present invention to provide a warning system designed to provide the pivot of a high performance aircraft such as a fighter/attack aircraft cruising at low altitude with a warning indicating a dangerous flight condition in sufficient time to permit him to take corrective action.
It is another object of the preset inane-lion to provide the pilot of an aircraft executing turning and banking maneuvers near the ground with a warning of a dangerous condition such as an excessive descent rate in sufficient time to permit the pilot to take corrective action.
It is yet another object of the present invention to provide a warning of an excessive radio altitude loss during take-off into rising terrain.
The mission flight profile of a fighter/attack aircraft contains low altitude cruise and attack segments, and if the pilot becomes disk treated or disoriented, there us a danger of inadver-tent descent into terrain or flight into slowly rising terrain. The danger of flying into rising terrain exists primarily during take-off, and during low alit-tune cruise. The danger of inadvertent descent is greatest during low level maneuvers requiring high roll angles, such as are encountered during an attack portion of a flight, because the pilot can easily become distracted and disoriented during such maneuvers, and because aircraft tend to sink when they are sub-jetted to high roll angles.
Therefore, in accordance with a preferred embodiment of the invention there is provided a warn-in system that senses the altitude of the aircraft above the ground utilizing a radio altimeter or the like, and provides a specific aural warning, such as 'TOO LOW" to the pilot if the aircraft descends below a predetermined minimum desired altitude above ground, thereby providing protection during low altitude cruise phases of operation. The predetermined minimum desired altitude is typically the minimum decision altitude which is manually set by the minimum decision altitude marker or altimeter "bug' present on a radio altimeter indicator.
Also, in order to provide a warning during take-off into rising terrain, or during an inadvertent descent before the minimum decision altitude is reached, the system is provided with an accumulator that monitors the radio altitude after take-off and stores the highest altitude reached after take-off. In the event that the aircraft descends below a predetermined percentage of the maximum radio altitude reached prior to reaching the minimum decision altitude, a warning is also generated. Typically, this warning will be the same "TOO LOW" warning that is generated if the minimum decision altitude is penetrated in order to indicate to the pilot that he is zoo low.
In addition the system monitors the roll angle of the aircraft and generates a second specific warning in the event that the aircraft is below a second predetermined altitude, and exceeds a predator-mined descent rate which varies as a function of the roll angle of the aircraft in order to warn the pilot that the aircraft is descending at an excessively high rate during a roll maneuver. The warning given should be specific enough to enable the pilot to diagnose the problem quickly, and in the present embodiment, a warning such as the warning "TOLL OUT"
or similar term is provided.
DESCRIPTION OF TUBE DRAWING
These and other objects and advantages of the present invention will become apparent upon con-side ration of the following detailed description and attached drawing, wherein:
FIG. 1 is a logical block diagram of the warning system according to the invention;
Fig 2 is a graph illustrating the relation-ship between airspeed and radio altitude where warnings may be generated and FIG. 3 is a graph showing the relationship between barometric altitude rate and roll angle require s--to generate a warning that the aircraft is descending at an excessive rate during a roll maneuver DETAILED DESCRIPTION OF THE PREFERRED EMBO IMMUNITY
Referring now to the drawing, with particular attention to FIG. 1, there is illustrated an embodiment of a ground proximity warning system according to the invention particularly useful for providing warnings of unsafe flight conditions during low level maneuver-in generally designated by the reference numeral 10.
The system 10 according to the invention is illustrated in FIG. 1 in functional or logical block diagram form as a series of gates; comparators, flip-flops and the like for purposes of illustration; however, it should be understood that the actual implementation of the logic can be other than as shown in FIG. 1, with various digital and analog implementations being possible.
The signals used by the warning system as described include radio altitude, barometric altitude rote, airspeed, engine RPM, roll angle of the aircraft, the 23 minimum decision altitude and signals indicating the position of the aircraft landing gear along with various validity signals. Depending on the typo of aircraft in which the warning system it installed, the signals shown in FIG. 1 can be obtained from individual incitory-mints such as a barometric altimeter 12, a barometric altitude rate circuit 14, a radio altimeter 16 and a gyroscopic platform 18~ as well as various discrete circuit elements such as a discrete element indicating the position of the landing gear. These signals may also be obtained from a digital data bus in certain newer aircraft.
As previously stated, the system according to the invention is designed to provide different warnings during different phases of aircraft operation.
For example, the system is designed to provide a first I to warning, such as, for example, an aural or voice warn-in "TOO LOW" should the aircraft descend below the minimum decision altitude during low level cruise.
This warning will also be generated if the aircraft should lose a predetermined percentage of the altitude attained after take-off, but prior to reaching the minimum decision altitude. In addition, the system is designed to provide a second specific warning, such as, for example, the aural or voice signal "ROLL OUT"
should the aircraft descend too rapidly during roll maneuver. Consequently, logic circuitry is provided to indicate to the system the particular flight place in which the aircraft is operating, i.e., take-off, low level cruise or low level maneuvering so that the appropriate warning will be generated should certain flight parameters be exceeded. This function is pro-voided by the logic circuitry including AND gates 20, 22, 24, 26, and 28, an OR gate 30, a pair of set/reset flip-flops 32 and 34, a transition detector 36 and a switch 38 controlled by the flip flop 34~
Because thy system is designed to be opera-tonal to provide warnings during take-off, low level cruise and low level maneuvering phases of flight, certain determinations must be made to determine whether he aircraft is indeed in one of the foremen-toned phases. The initial determinations are made by the AND gate 20 which provides an enabling signal to the AND gates 22 and 24 only if certain conditions are met. These conditions are that there is no weight on the wheels, indicating that the aircraft is actually flying, that the gear is up and the aircraft is not flying slower than 200 knots, thereby indicating that the aircraft is not in a landing configuration. Also, for the system to he operational the barometric alit-meter 12, the barometric rate circuit 14 and the radio altimeter must be operating properly. Consequently signals indicating that the barometric altimeter and radio altimeter have not been inhibited, as well as a signal indicating that the rate of the radio altitude is not excessive are applied to the gate 20 to cause the gate 20 to enable the gates 22 and 24 only if the signals from the barometric altimeter 12, the barometric rate circuit 14 and the radio altimeter 16 are valid.
In addition to determining whether the air-craft is flying in a configuration other than a land in configuration and that the instruments are operate in properly, it is necessary to determine whether the aircraft is in an approach phase, or in a take-off or a go-around after missed approach phase, This determination is made by the gates AND 26 and 28, the OR gate 30 and the set/reset flip-flop 32. In the implementation shown, a takeoff or a go-around after a missed approach is indicated only if both the condo-lions that take-off power is present and that the landing gear is up are met. If both conditions are met, the set/reset flip-flop 32 is reset. Signals indicative of take-off power that are applied to the gate 26 can be obtained from various sources, for example, from a comparator circuit that provides an enabling signal to the gate 26 when the RPM of the engine is sufficiently high to indicate take-off power, or from a discrete element indicating throttle post-lion. An engine tachometer, which indicates for example, the RPM of the primary compressor of a jet engine, can be used to provide the engine RPM signal, and a predetermined RPM, for example, 90% of maximum engine RPM, can be used to indic2~i_e take-off power.
The gear up signal can readily be obtained prom another discrete element, such as, from a switch operated by I
the landing gear or by the landing gear control handle in the cockpit.
An approach condition is indicated by the gates 30 and 28 when the gear is not up or the aircraft is below l00 feet and the engine is not producing take-off power and the speed of the aircraft is below 200 knots. An approach condition indication from the gate 28 serves to set the flip-flop 32.
In operation, during the take-off phase of lo flight, the set/reset flip-flop 32 is reset, thereby causing the Q output of the flip-flop 32 to change from a high state to a low state. This transition is detected by the transition detector 36 which generates an output pulse in response to the transition and sets a set/reset flip-flop 34. This causes the Q
output of the flip-flop 34 to operate the switch 38 to the position shown in FIG. l, thereby to connect one input of the gate 22 to circuitry including a too low comparator 40, a scaling circuit 42 and a radio altitude accumulator 44. These devices determine when a "TOO LOW" warning should be generated by a generator 46 during the take-off mode of operation.
After the aircraft has completed its take-off, as evidenced by the radio altitude exceeding the minimum decision altitude (MA), an MY comparator 50 provides a signal indicating that the aircraft has exceeded the minimum decision altitude in order to reset the input of the flip-flop 34, thereby resetting the flip-flop 34. When the flip-flop 34 is reset, the switch 38 is operated to disconnect the gate 22 from the too low comparator 40 and connected to a LESS THAN MA output of the MA comparator 50, thereby making the system responsive to any descent below the minimum decision altitude. Consequently, if the aircraft drops below the minimum decision altitude when in this mode, the warning generator 45 will 9ener-ate the "TOO LOW" warning and apply it to the trays-dicer 48.
As long as the altitude of the aircraft is below the minimum decision altitude plus a predator-mined increment, such as, for example, 100 feet, but not below the minimum decision altitude, the AND gate 24 is enabled by the comparator 50 via the GREATER
THAN MA and LESS THAN MA + 100 FEET signals applied to two of its inputs. when so enabled, the AND gate 24 is made responsive to a pair of comparators 52 and 54 to operate a second warning generator 56 which generates a second warning such as, for example, "ROLL
OUT" when the descent rate of the aircraft exceeds a predetermined level for a given roll angle.
Discussing the operation in greater detail as the aircraft takes off, the flip-flop 32 is reset, thereby causing the transition detector 36 to provide an output pulse to set the flip-flop 34 to thereby connect the gate 22 to the comparator 40. The output pulse from the transition detector 36 also resets the radio altitude accumulator to zero, or to a predator-mined low value setting, such as; for example, 50 feet. The radio altitude accumulator receives the altitude signals from he radio altimeter 16, and retains the highest altitude reached since take-off.
This maximum value of radio altitude reached since take-off is applied to a scaling circuit which multi-plies by a scaling factor, for example, 75% and applies to the too low comparator 40 which controls the opera-lion of the too low warning generator 46 during the take-off phase of operation The radio altimeter signal is also applied to the too low comparator 40, and as long as the radix altitude remains above the maximum radio altitude -10 ' multiplied by the sealing factor, no warning is ever axed. however, if the radio altitude drops below the scaled maximum altitude, for example, below 75~ of the maximum altitude reached during the flight, the comparator 40 will provide a signal to the gate 22.
this signal will cause the gate 22 to provide a signal to the "TOO LOW" warning generator 46 and pause the generator 46 to generate the TOO LOW warning and apply it, either directly or indirectly, to the trays-dicer 48, provided that the other input of the gut is enabled by the gate 20.
The radio altitude signal from the altimeter 16 is also applied to the MA comparator 50 which monitors the radio altitude signal from the radio altimeter 1 and provides a GREATER THAN MA signal to the flip-flop 34 when the radio alit use exceeds the minimum decision altitude. This signal resets the flip-flop 34 and causes the switch 38 to connect the gate 22 Jo the MA comparator 50 so that any warning generated will be controlled by MA comparator 50. The MA
comparator 50 continues to monitor the radio altitude, and no warning is initiated as long as the radio altitude remains above the minimum decision altitude. However, if the altitude drops below the minimum decision altitude and the gate 22 is enabled by the gate 20, the MA come portray will provide a LESS THAN MA signal to the gate 22 to cause the gate 22 to initiate the "TOO
LOW warning by the warning generator 46.
As the aircraft climbs above the minimum decision altitude, but remains below the minimum decision altitude plus a predetermined increment, such as, 100 feet and as long as the gate 20 provides an enabling signal, the gate 24 will be under the control of a roll-out comparator 52 and a roll angle comparator 54. The function of the comparators 52 I I
and 54 is to monitor the roll angle and barometric descent rate of the aircraft, and to cause the gate 24 to initiate a warning by the warning generator 56 if an unsafe combination of descent rate and roll angle exists.
As previously discussed, aircraft tend to descend as the roll angle is increased. However, this tendency is not significant until the roll angle exceeds a predetermined level, such as, for example, 45 for modern fighter/attack aircraft such as the Fairchild Aye. Consequently, the roll angle compare-ion 54 monitors the roll angle signal generated by the gyro platform 18, or similar device indicating the roll angle of the aircraft, and provides an enabling signal to the gate 24 when the roll angle reaches the roll angle at which the aircraft tends to sink. this permits the "ROLL one warning to be generated by the generator 56 if the barometric descent rate exceeds the maximum rate permitted for a given roll angle, as determined by the roll-out come portray 52. The conditions necessary for the "ROLL
OUT" warning to be generated are further discussed in connection with the discussion of FIG. 3.
Referring to FIG. 2, there is shown a graph illustrating the conditions necessary to generate the "TOO LOW" warning and to enable the TROLL OUT" warning as a function of airspeed and altitude. These condo-lions are illustrated by the two shaded areas on the graph. As is apparent from FIG. 2, neither warning can be generated as long as the airspeed of the air-craft is below a predetermined value, in this embody-mint 200 knots. As long as the airspeed of the air-craft exceeds 200 knots, and the other previously discussed conditions are met, the "TOO LOW" warning will be given whenever the aircraft drops below the I
minimum decision altitude, or below a prede~rmined percentage, for example 75%, of the maximum altitude reached on take-off or go-around prior to exceeding the minimum decision altitude.
When the altitude of the aircraft exceeds the minimum decision altitude, but is below the mini-mum decision altitude plus a predetermined increment, such as, for example 100 feet, the "ROLL OUT" warning is enabled. However, the "ROLL OUT warning is not automatically generated when the "ROLL OUT" warning boundary illustrated in FIG 2 is penetrated, as is the case when the "TOO LOW" warning boundary is penes treated. Rather, the TROLL OUT" warning mode is only enabled, but the actual warning is produced only if the toll angle exceeds a predetermined angle, for example, 45, and if the descent rate penetrates the boundary of the descent rate curve (JIG. 3) which defines the maximum permissible descent raze as a function of roll angle.
A descent rate curve which has been found to be particularly suitable for use in fighter/attack aircraft it illustrated in FIG. 3. The shaded area shows the relationship between roll angle and baron metric descent rate necessary to generate the "ROLL
OUT" warning. As can be seen from FIG. I the "ROLL
OUT" warning is not generated until the roll angle reaches 45, at which point the "ROLL OUT' warning is generated if the barometric altitude descent rate exceeds 100 feet per minute. As the roll angle is increased to 60, only 50 feet per minute of descent rate is required to initiate a warning, and when the roll angle reaches 90, no descent at all can be tolerated because the lift provided by the wing under this condition is virtually zero.
:~23~
Obviously" many modifica t ions and variations of the present invention are possible in light of the above teachings. Thus, it is to be understood that, within the scope of the appended claims, the invention 5 may be pry act iced other so than as specs f icily desk cried above .
BACKGROUND OF THE INVENTION
Field of the Invention This invention relates generally to ground proximity warning systems, and more particularly to a system that protects an aircraft during low altitude maneuvers if the aircraft should descend below a pro-determined minimum altitude above grounder if the aircraft exceeds a predetermined descent rate while performing turning maneuvers or other maneuvers requiring a roll. Distinct specific warnings are given in order to inform the pilot of the specific action what must be taken to recover from a dangerous flight profile.
Description of the Prior Art Ground proximity warning systems that warn a pilot of a dangerous flight profile are known These systems provide warnings to the pilot of an aircraft under various unsafe flying conditions including flying below a preset minimum altitude, and permitting the aircraft to attain an excessive descent rate after take-off or on approach . An example of a system that provides a pilot with a warning if he drops below a predetermined minimum desired altitude is a system that compares the radio altitude with the minimum decision altitude setting, or "bug" setting on the radio altimeter, and provides an aural or visual warning if the radio altitude dross beloli the set minimum decision altitude. Examples of systems that provide a warning to a pilot during a takeoff or a missed approach phase of ~Z3~ 7 operation if the aircraft should descend at an excessive barometric rate or lose a predetermined amount of barometric altitude are disclosed in United States patent Nos. 3,946,358; 3,947,~08, 3,947,810 and 4,319,218, assigned to the same assignee as the present invention.
While these systems serve to provide the pilot with a warning in the event that the aircraft drops below a preset minimum desired altitude above ground, or if the aircraft descends excessively after take-off or a missed approach, such systems are designed primarily for transport aircraft that do not normally fly at low altitudes or execute turns or other severe or violent maneuvers Lear the ground. Conseauentl~, such systems would not normally provide adequate warn-in to the pilot of a highly maneuverable aircraft such as, for example, a fighter/attack aircraft execute in tactical maneuvers near the ground.
SUMMARY OF THE INVENTION
Accordingly, it is an object of the present invention to provide a warning system that overcomes many of the disadvantages of the prior art warning systems during high speed, low level maneuvering phases of aircraft operation.
It is another object of the present invention to provide a warning system designed to provide the pivot of a high performance aircraft such as a fighter/attack aircraft cruising at low altitude with a warning indicating a dangerous flight condition in sufficient time to permit him to take corrective action.
It is another object of the preset inane-lion to provide the pilot of an aircraft executing turning and banking maneuvers near the ground with a warning of a dangerous condition such as an excessive descent rate in sufficient time to permit the pilot to take corrective action.
It is yet another object of the present invention to provide a warning of an excessive radio altitude loss during take-off into rising terrain.
The mission flight profile of a fighter/attack aircraft contains low altitude cruise and attack segments, and if the pilot becomes disk treated or disoriented, there us a danger of inadver-tent descent into terrain or flight into slowly rising terrain. The danger of flying into rising terrain exists primarily during take-off, and during low alit-tune cruise. The danger of inadvertent descent is greatest during low level maneuvers requiring high roll angles, such as are encountered during an attack portion of a flight, because the pilot can easily become distracted and disoriented during such maneuvers, and because aircraft tend to sink when they are sub-jetted to high roll angles.
Therefore, in accordance with a preferred embodiment of the invention there is provided a warn-in system that senses the altitude of the aircraft above the ground utilizing a radio altimeter or the like, and provides a specific aural warning, such as 'TOO LOW" to the pilot if the aircraft descends below a predetermined minimum desired altitude above ground, thereby providing protection during low altitude cruise phases of operation. The predetermined minimum desired altitude is typically the minimum decision altitude which is manually set by the minimum decision altitude marker or altimeter "bug' present on a radio altimeter indicator.
Also, in order to provide a warning during take-off into rising terrain, or during an inadvertent descent before the minimum decision altitude is reached, the system is provided with an accumulator that monitors the radio altitude after take-off and stores the highest altitude reached after take-off. In the event that the aircraft descends below a predetermined percentage of the maximum radio altitude reached prior to reaching the minimum decision altitude, a warning is also generated. Typically, this warning will be the same "TOO LOW" warning that is generated if the minimum decision altitude is penetrated in order to indicate to the pilot that he is zoo low.
In addition the system monitors the roll angle of the aircraft and generates a second specific warning in the event that the aircraft is below a second predetermined altitude, and exceeds a predator-mined descent rate which varies as a function of the roll angle of the aircraft in order to warn the pilot that the aircraft is descending at an excessively high rate during a roll maneuver. The warning given should be specific enough to enable the pilot to diagnose the problem quickly, and in the present embodiment, a warning such as the warning "TOLL OUT"
or similar term is provided.
DESCRIPTION OF TUBE DRAWING
These and other objects and advantages of the present invention will become apparent upon con-side ration of the following detailed description and attached drawing, wherein:
FIG. 1 is a logical block diagram of the warning system according to the invention;
Fig 2 is a graph illustrating the relation-ship between airspeed and radio altitude where warnings may be generated and FIG. 3 is a graph showing the relationship between barometric altitude rate and roll angle require s--to generate a warning that the aircraft is descending at an excessive rate during a roll maneuver DETAILED DESCRIPTION OF THE PREFERRED EMBO IMMUNITY
Referring now to the drawing, with particular attention to FIG. 1, there is illustrated an embodiment of a ground proximity warning system according to the invention particularly useful for providing warnings of unsafe flight conditions during low level maneuver-in generally designated by the reference numeral 10.
The system 10 according to the invention is illustrated in FIG. 1 in functional or logical block diagram form as a series of gates; comparators, flip-flops and the like for purposes of illustration; however, it should be understood that the actual implementation of the logic can be other than as shown in FIG. 1, with various digital and analog implementations being possible.
The signals used by the warning system as described include radio altitude, barometric altitude rote, airspeed, engine RPM, roll angle of the aircraft, the 23 minimum decision altitude and signals indicating the position of the aircraft landing gear along with various validity signals. Depending on the typo of aircraft in which the warning system it installed, the signals shown in FIG. 1 can be obtained from individual incitory-mints such as a barometric altimeter 12, a barometric altitude rate circuit 14, a radio altimeter 16 and a gyroscopic platform 18~ as well as various discrete circuit elements such as a discrete element indicating the position of the landing gear. These signals may also be obtained from a digital data bus in certain newer aircraft.
As previously stated, the system according to the invention is designed to provide different warnings during different phases of aircraft operation.
For example, the system is designed to provide a first I to warning, such as, for example, an aural or voice warn-in "TOO LOW" should the aircraft descend below the minimum decision altitude during low level cruise.
This warning will also be generated if the aircraft should lose a predetermined percentage of the altitude attained after take-off, but prior to reaching the minimum decision altitude. In addition, the system is designed to provide a second specific warning, such as, for example, the aural or voice signal "ROLL OUT"
should the aircraft descend too rapidly during roll maneuver. Consequently, logic circuitry is provided to indicate to the system the particular flight place in which the aircraft is operating, i.e., take-off, low level cruise or low level maneuvering so that the appropriate warning will be generated should certain flight parameters be exceeded. This function is pro-voided by the logic circuitry including AND gates 20, 22, 24, 26, and 28, an OR gate 30, a pair of set/reset flip-flops 32 and 34, a transition detector 36 and a switch 38 controlled by the flip flop 34~
Because thy system is designed to be opera-tonal to provide warnings during take-off, low level cruise and low level maneuvering phases of flight, certain determinations must be made to determine whether he aircraft is indeed in one of the foremen-toned phases. The initial determinations are made by the AND gate 20 which provides an enabling signal to the AND gates 22 and 24 only if certain conditions are met. These conditions are that there is no weight on the wheels, indicating that the aircraft is actually flying, that the gear is up and the aircraft is not flying slower than 200 knots, thereby indicating that the aircraft is not in a landing configuration. Also, for the system to he operational the barometric alit-meter 12, the barometric rate circuit 14 and the radio altimeter must be operating properly. Consequently signals indicating that the barometric altimeter and radio altimeter have not been inhibited, as well as a signal indicating that the rate of the radio altitude is not excessive are applied to the gate 20 to cause the gate 20 to enable the gates 22 and 24 only if the signals from the barometric altimeter 12, the barometric rate circuit 14 and the radio altimeter 16 are valid.
In addition to determining whether the air-craft is flying in a configuration other than a land in configuration and that the instruments are operate in properly, it is necessary to determine whether the aircraft is in an approach phase, or in a take-off or a go-around after missed approach phase, This determination is made by the gates AND 26 and 28, the OR gate 30 and the set/reset flip-flop 32. In the implementation shown, a takeoff or a go-around after a missed approach is indicated only if both the condo-lions that take-off power is present and that the landing gear is up are met. If both conditions are met, the set/reset flip-flop 32 is reset. Signals indicative of take-off power that are applied to the gate 26 can be obtained from various sources, for example, from a comparator circuit that provides an enabling signal to the gate 26 when the RPM of the engine is sufficiently high to indicate take-off power, or from a discrete element indicating throttle post-lion. An engine tachometer, which indicates for example, the RPM of the primary compressor of a jet engine, can be used to provide the engine RPM signal, and a predetermined RPM, for example, 90% of maximum engine RPM, can be used to indic2~i_e take-off power.
The gear up signal can readily be obtained prom another discrete element, such as, from a switch operated by I
the landing gear or by the landing gear control handle in the cockpit.
An approach condition is indicated by the gates 30 and 28 when the gear is not up or the aircraft is below l00 feet and the engine is not producing take-off power and the speed of the aircraft is below 200 knots. An approach condition indication from the gate 28 serves to set the flip-flop 32.
In operation, during the take-off phase of lo flight, the set/reset flip-flop 32 is reset, thereby causing the Q output of the flip-flop 32 to change from a high state to a low state. This transition is detected by the transition detector 36 which generates an output pulse in response to the transition and sets a set/reset flip-flop 34. This causes the Q
output of the flip-flop 34 to operate the switch 38 to the position shown in FIG. l, thereby to connect one input of the gate 22 to circuitry including a too low comparator 40, a scaling circuit 42 and a radio altitude accumulator 44. These devices determine when a "TOO LOW" warning should be generated by a generator 46 during the take-off mode of operation.
After the aircraft has completed its take-off, as evidenced by the radio altitude exceeding the minimum decision altitude (MA), an MY comparator 50 provides a signal indicating that the aircraft has exceeded the minimum decision altitude in order to reset the input of the flip-flop 34, thereby resetting the flip-flop 34. When the flip-flop 34 is reset, the switch 38 is operated to disconnect the gate 22 from the too low comparator 40 and connected to a LESS THAN MA output of the MA comparator 50, thereby making the system responsive to any descent below the minimum decision altitude. Consequently, if the aircraft drops below the minimum decision altitude when in this mode, the warning generator 45 will 9ener-ate the "TOO LOW" warning and apply it to the trays-dicer 48.
As long as the altitude of the aircraft is below the minimum decision altitude plus a predator-mined increment, such as, for example, 100 feet, but not below the minimum decision altitude, the AND gate 24 is enabled by the comparator 50 via the GREATER
THAN MA and LESS THAN MA + 100 FEET signals applied to two of its inputs. when so enabled, the AND gate 24 is made responsive to a pair of comparators 52 and 54 to operate a second warning generator 56 which generates a second warning such as, for example, "ROLL
OUT" when the descent rate of the aircraft exceeds a predetermined level for a given roll angle.
Discussing the operation in greater detail as the aircraft takes off, the flip-flop 32 is reset, thereby causing the transition detector 36 to provide an output pulse to set the flip-flop 34 to thereby connect the gate 22 to the comparator 40. The output pulse from the transition detector 36 also resets the radio altitude accumulator to zero, or to a predator-mined low value setting, such as; for example, 50 feet. The radio altitude accumulator receives the altitude signals from he radio altimeter 16, and retains the highest altitude reached since take-off.
This maximum value of radio altitude reached since take-off is applied to a scaling circuit which multi-plies by a scaling factor, for example, 75% and applies to the too low comparator 40 which controls the opera-lion of the too low warning generator 46 during the take-off phase of operation The radio altimeter signal is also applied to the too low comparator 40, and as long as the radix altitude remains above the maximum radio altitude -10 ' multiplied by the sealing factor, no warning is ever axed. however, if the radio altitude drops below the scaled maximum altitude, for example, below 75~ of the maximum altitude reached during the flight, the comparator 40 will provide a signal to the gate 22.
this signal will cause the gate 22 to provide a signal to the "TOO LOW" warning generator 46 and pause the generator 46 to generate the TOO LOW warning and apply it, either directly or indirectly, to the trays-dicer 48, provided that the other input of the gut is enabled by the gate 20.
The radio altitude signal from the altimeter 16 is also applied to the MA comparator 50 which monitors the radio altitude signal from the radio altimeter 1 and provides a GREATER THAN MA signal to the flip-flop 34 when the radio alit use exceeds the minimum decision altitude. This signal resets the flip-flop 34 and causes the switch 38 to connect the gate 22 Jo the MA comparator 50 so that any warning generated will be controlled by MA comparator 50. The MA
comparator 50 continues to monitor the radio altitude, and no warning is initiated as long as the radio altitude remains above the minimum decision altitude. However, if the altitude drops below the minimum decision altitude and the gate 22 is enabled by the gate 20, the MA come portray will provide a LESS THAN MA signal to the gate 22 to cause the gate 22 to initiate the "TOO
LOW warning by the warning generator 46.
As the aircraft climbs above the minimum decision altitude, but remains below the minimum decision altitude plus a predetermined increment, such as, 100 feet and as long as the gate 20 provides an enabling signal, the gate 24 will be under the control of a roll-out comparator 52 and a roll angle comparator 54. The function of the comparators 52 I I
and 54 is to monitor the roll angle and barometric descent rate of the aircraft, and to cause the gate 24 to initiate a warning by the warning generator 56 if an unsafe combination of descent rate and roll angle exists.
As previously discussed, aircraft tend to descend as the roll angle is increased. However, this tendency is not significant until the roll angle exceeds a predetermined level, such as, for example, 45 for modern fighter/attack aircraft such as the Fairchild Aye. Consequently, the roll angle compare-ion 54 monitors the roll angle signal generated by the gyro platform 18, or similar device indicating the roll angle of the aircraft, and provides an enabling signal to the gate 24 when the roll angle reaches the roll angle at which the aircraft tends to sink. this permits the "ROLL one warning to be generated by the generator 56 if the barometric descent rate exceeds the maximum rate permitted for a given roll angle, as determined by the roll-out come portray 52. The conditions necessary for the "ROLL
OUT" warning to be generated are further discussed in connection with the discussion of FIG. 3.
Referring to FIG. 2, there is shown a graph illustrating the conditions necessary to generate the "TOO LOW" warning and to enable the TROLL OUT" warning as a function of airspeed and altitude. These condo-lions are illustrated by the two shaded areas on the graph. As is apparent from FIG. 2, neither warning can be generated as long as the airspeed of the air-craft is below a predetermined value, in this embody-mint 200 knots. As long as the airspeed of the air-craft exceeds 200 knots, and the other previously discussed conditions are met, the "TOO LOW" warning will be given whenever the aircraft drops below the I
minimum decision altitude, or below a prede~rmined percentage, for example 75%, of the maximum altitude reached on take-off or go-around prior to exceeding the minimum decision altitude.
When the altitude of the aircraft exceeds the minimum decision altitude, but is below the mini-mum decision altitude plus a predetermined increment, such as, for example 100 feet, the "ROLL OUT" warning is enabled. However, the "ROLL OUT warning is not automatically generated when the "ROLL OUT" warning boundary illustrated in FIG 2 is penetrated, as is the case when the "TOO LOW" warning boundary is penes treated. Rather, the TROLL OUT" warning mode is only enabled, but the actual warning is produced only if the toll angle exceeds a predetermined angle, for example, 45, and if the descent rate penetrates the boundary of the descent rate curve (JIG. 3) which defines the maximum permissible descent raze as a function of roll angle.
A descent rate curve which has been found to be particularly suitable for use in fighter/attack aircraft it illustrated in FIG. 3. The shaded area shows the relationship between roll angle and baron metric descent rate necessary to generate the "ROLL
OUT" warning. As can be seen from FIG. I the "ROLL
OUT" warning is not generated until the roll angle reaches 45, at which point the "ROLL OUT' warning is generated if the barometric altitude descent rate exceeds 100 feet per minute. As the roll angle is increased to 60, only 50 feet per minute of descent rate is required to initiate a warning, and when the roll angle reaches 90, no descent at all can be tolerated because the lift provided by the wing under this condition is virtually zero.
:~23~
Obviously" many modifica t ions and variations of the present invention are possible in light of the above teachings. Thus, it is to be understood that, within the scope of the appended claims, the invention 5 may be pry act iced other so than as specs f icily desk cried above .
Claims (24)
1. A warning system for alerting the pilot of an aircraft of a dangerous flight condition after take-off and during low altitude maneuvering, comprising:
means for monitoring the altitude above ground of the aircraft after take-off and storing an indication of the highest altitude above ground reached during the flight;
means for selecting a minimum desired altitude above ground;
means responsive to a signal representative of the altitude above ground of the aircraft, to said altitude indication storing means and to said minimum altitude selecting means for providing a first specific warning if the altitude of the aircraft drops below the minimum desired altitude or below a predetermined percentage of the highest altitude above ground reached during the flight if the aircraft has not yet reached the predetermined minimum desired altitude; and means responsive to a signal representative of the roll angle of the aircraft for rendering said system operative to generate a second specific warning when the roll angle of the aircraft exceeds a predetermined amount.
2. A warning system as recited in claim 1 further including means responsive to a signal representative of the
means for monitoring the altitude above ground of the aircraft after take-off and storing an indication of the highest altitude above ground reached during the flight;
means for selecting a minimum desired altitude above ground;
means responsive to a signal representative of the altitude above ground of the aircraft, to said altitude indication storing means and to said minimum altitude selecting means for providing a first specific warning if the altitude of the aircraft drops below the minimum desired altitude or below a predetermined percentage of the highest altitude above ground reached during the flight if the aircraft has not yet reached the predetermined minimum desired altitude; and means responsive to a signal representative of the roll angle of the aircraft for rendering said system operative to generate a second specific warning when the roll angle of the aircraft exceeds a predetermined amount.
2. A warning system as recited in claim 1 further including means responsive to a signal representative of the
Claim 2 continued...
power output of the engine and to the position of the landing gear for rendering said system operative to provide said warning indication if the altitude drops below said predetermined percentage of the highest altitude reached if the landing gear is up and the engine is at take-off power.
power output of the engine and to the position of the landing gear for rendering said system operative to provide said warning indication if the altitude drops below said predetermined percentage of the highest altitude reached if the landing gear is up and the engine is at take-off power.
3. A warning system as recited in claim 1 further including means responsive to a signal representative of the airspeed of the aircraft for rendering said system operative to provide said warning indication only when the airspeed of the aircraft exceeds a predetermined speed.
4. A warning system as recited in claim 3 wherein said predetermined airspeed is approximately 200 knots.
5. A warning system as recited in claim 1 further including means responsive to a signal representative of the descent rate of the aircraft for causing said second specific warning to be given only when the roll angle and descent rate of the aircraft each exceed a predetermined amount.
6. A warning system as recited in claim 5 wherein said second specific warning is given at an altitude range that is higher than the altitude range at which said first specific warning is given.
7. A warning system as recited in claim 6 wherein the range of altitudes at which said second specific warning is given is approximately 100 feet higher than the range of altitudes at which said first specific warning is given.
8. A warning system as recited in claim 1 wherein said system is rendered operative to generate said second specific warning when the roll angle of the aircraft exceeds approximately 45°.
9. A warning system as recited in claim 1 wherein said predetermined percentage of the highest altitude reached is approximately 75% of the altitude above ground reached during the flight.
10. A warning system for alerting the pilot of an aircraft of a dangerous flight condition after take-off and during low altitude maneuvering, comprising:
means for providing a signal representative of the altitude of the aircraft above ground;
means responsive to said altitude above ground signal providing means for storing an indication of the highest altitude above ground reached after take-off, means responsive to said altitude above ground signal providing means and to said altitude indication storing means for providing a warning if the altitude signal provided by the altitude signal providing means drops to a predetermined percentage of the highest altitude reached after take-off; and
10. A warning system for alerting the pilot of an aircraft of a dangerous flight condition after take-off and during low altitude maneuvering, comprising:
means for providing a signal representative of the altitude of the aircraft above ground;
means responsive to said altitude above ground signal providing means for storing an indication of the highest altitude above ground reached after take-off, means responsive to said altitude above ground signal providing means and to said altitude indication storing means for providing a warning if the altitude signal provided by the altitude signal providing means drops to a predetermined percentage of the highest altitude reached after take-off; and
Claim 10 continued...
means for providing a signal representative of the roll angle of the aircraft, means for providing a signal representative of the descent rate of the aircraft, and means responsive to said roll angle signal providing means and said descent rate signal providing means for generating a second warning if both the airspeed and descent rate exceed predetermined values.
means for providing a signal representative of the roll angle of the aircraft, means for providing a signal representative of the descent rate of the aircraft, and means responsive to said roll angle signal providing means and said descent rate signal providing means for generating a second warning if both the airspeed and descent rate exceed predetermined values.
11. A warning system as recited in claim 10 wherein said altitude signal providing means includes a radio altimeter.
12. A warning system as recited in claim 11 wherein said radio altimeter includes means for manually selecting a predetermined altitude, wherein said system is responsive to said minimum altitude selecting means for providing a warning if the altitude of the aircraft drops below the minimum altitude after having exceeded the minimum altitude.
13. A warning system as recited in claim 10 further including means for providing a signal representative of the airspeed of the aircraft, and wherein said system includes means responsive to said airspeed representative signal for rendering said system operative to generate the warning only if the airspeed exceeds the predetermined speed.
14. A warning system as rcited in claim 13 wherein said predetermined airspeed is approximately 200 knots.
15. A warning system as recited in claim 10 wherein the predetermined value of descentrate required to generate said second warning is an inverse function of the roll angle.
16. A warning system for alerting the pilot of an aircraft of a dangerous flight condition after take-off and during low altitude maneuvering, comprising:
means for providing a signal representative of the altitude above ground of the aircraft;
means responsive to said altitude above ground signal providing means for storing an indication of the highest altitude reached by the aircraft after take-off;
means for manually setting a minimum altitude;
means for providing a signal representative of the descent rate of the aircraft;
means for providing a signal representative of the roll angle of the aircraft;
means responsive to said altitude signal providing means, to said manually settable minimum altitude setting means and to said highest altitude storing means for providing a first specific warning if the aircraft descends below a predetermined percentage of the maximum altitude reached prior to reaching the manually set minimum altitude, and for generating said first specific warning if the aircraft drops below the manually set minimum altitude after having exceeds it; and
16. A warning system for alerting the pilot of an aircraft of a dangerous flight condition after take-off and during low altitude maneuvering, comprising:
means for providing a signal representative of the altitude above ground of the aircraft;
means responsive to said altitude above ground signal providing means for storing an indication of the highest altitude reached by the aircraft after take-off;
means for manually setting a minimum altitude;
means for providing a signal representative of the descent rate of the aircraft;
means for providing a signal representative of the roll angle of the aircraft;
means responsive to said altitude signal providing means, to said manually settable minimum altitude setting means and to said highest altitude storing means for providing a first specific warning if the aircraft descends below a predetermined percentage of the maximum altitude reached prior to reaching the manually set minimum altitude, and for generating said first specific warning if the aircraft drops below the manually set minimum altitude after having exceeds it; and
Claim 16 continued....
means responsive to said roll angle signal providing means and said descent rate signal providing means for providing a second specific warning when the aircraft is above said minimum altitude and the descent rate exceeds a predetermined rate that is a function of roll angle.
means responsive to said roll angle signal providing means and said descent rate signal providing means for providing a second specific warning when the aircraft is above said minimum altitude and the descent rate exceeds a predetermined rate that is a function of roll angle.
17. A warning system as recited in claim 16 wherein said second specific warning is generated only if the roll angle exceeds a predetermined value.
18. A warning system as recited in claim 17 wherein the predetermined value of roll angle required to generate said second specific warning is approximately 45°.
19. A warning system as recited in claim 16 wherein the descent rate required to generate said second specific warning is an inverse function of roll angle.
20. warning system as recited inclaim 16 further including means responsive to the altitude above ground signal providing means for inhibiting the generation of said second specific warning when the altitude exceeds a predetermined altitude.
21. A warning system as recited in claim 16 wherein said second predetermined altitude is a predetermined increment above the manually set minimum altitude.
22. A warning system as recited in claim 21 wherein said predetermined increment is approximately 100 feet.
23. A warning system as recited in claim 16 further including means for providing a signal indicative of the position of the aircraft landing gear, means for providing an indication of the power output of the engine, and means responsive to said landing gear position signal providing means and said engine power indication providing means for rendering the system operative to generate warnings wren the landing gear is up and the engine is developing take-off power.
24. A warning system as recited in claim 23 wherein said engine power indication providing means includes a tachometer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000534230A CA1241083A (en) | 1983-05-13 | 1987-04-08 | System for alerting a pilot of a dangerous flight profile during low level maneuvering |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US49459083A | 1983-05-13 | 1983-05-13 | |
| US494,590 | 1983-05-13 |
Related Child Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000534230A Division CA1241083A (en) | 1983-05-13 | 1987-04-08 | System for alerting a pilot of a dangerous flight profile during low level maneuvering |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1234417A true CA1234417A (en) | 1988-03-22 |
Family
ID=23965099
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000449619A Expired CA1234417A (en) | 1983-05-13 | 1984-03-14 | System for alerting a pilot of a dangerous flight profile during low level maneuvering |
Country Status (15)
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| JP (1) | JPS59216795A (en) |
| AU (2) | AU548709B2 (en) |
| BE (1) | BE899643A (en) |
| CA (1) | CA1234417A (en) |
| CH (1) | CH660156A5 (en) |
| DE (1) | DE3417884A1 (en) |
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| GB (2) | GB2139588B (en) |
| GR (1) | GR82062B (en) |
| IL (1) | IL71348A (en) |
| IT (1) | IT1177721B (en) |
| NL (1) | NL8401531A (en) |
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Families Citing this family (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5001476A (en) * | 1983-05-13 | 1991-03-19 | Sundstrand Data Control, Inc. | Warning system for tactical aircraft |
| CA1243405A (en) * | 1985-02-22 | 1988-10-18 | Michael M. Grove | Configuration responsive descent rate warning system for aircraft |
| IL77860A0 (en) * | 1985-02-22 | 1986-09-30 | Sundstrand Data Control | Ground proximity warning system for aircraft |
| DE3621052A1 (en) * | 1986-06-24 | 1988-01-07 | Aerodata Flugmesstechnik Gmbh | Device for the automatic flight path guidance of aircraft along a guidance beam |
| CH671555A5 (en) * | 1986-09-10 | 1989-09-15 | Zermatt Air Ag | |
| US4916448A (en) * | 1988-02-26 | 1990-04-10 | The United States Of America As Represented By The Secretary Of The Air Force | Low altitude warning system for aircraft |
| US5864307A (en) * | 1996-02-19 | 1999-01-26 | Gec Marconi Limited | Aircraft terrain advisory system |
| FR2749676B1 (en) * | 1996-06-11 | 1998-09-11 | Sextant Avionique | ALTITUDE MANAGEMENT METHOD AND SYSTEM FOR AERODYNE |
| DE102007048956B4 (en) * | 2007-10-12 | 2019-02-14 | Airbus Operations Gmbh | Apparatus and method for providing a flight status signal |
| US8155804B2 (en) | 2007-10-12 | 2012-04-10 | Airbus Operations Gmbh | Device and method for providing a flight status signal |
| US8086361B2 (en) * | 2007-12-12 | 2011-12-27 | Honeywell International Inc. | Advisory system to aid pilot recovery from spatial disorientation during an excessive roll |
| EP2592381A1 (en) * | 2011-11-08 | 2013-05-15 | EADS Construcciones Aeronauticas, S.A. | Discrete signal consolidation device and method and aircraft with said device |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3946358A (en) * | 1974-06-19 | 1976-03-23 | Sundstrand Data Control, Inc. | Aircraft ground proximity warning instrument |
| US3947808A (en) * | 1975-01-13 | 1976-03-30 | Sundstrand Data Control, Inc. | Excessive descent rate warning system for aircraft |
| US3947810A (en) * | 1975-01-13 | 1976-03-30 | Sundstrand Data Control, Inc. | Negative climb rate after take-off warning system with predetermined loss of altitude inhibit |
| GB1567553A (en) * | 1976-06-14 | 1980-05-14 | Litton Industries Inc | Digital ground proximity warning systems |
| US4319218A (en) * | 1980-01-04 | 1982-03-09 | Sundstrand Corporation | Negative climb after take-off warning system with configuration warning means |
-
1984
- 1984-03-14 CA CA000449619A patent/CA1234417A/en not_active Expired
- 1984-03-26 IL IL71348A patent/IL71348A/en unknown
- 1984-04-10 AU AU26687/84A patent/AU548709B2/en not_active Ceased
- 1984-04-27 CH CH2085/84A patent/CH660156A5/en not_active IP Right Cessation
- 1984-05-08 GR GR74651A patent/GR82062B/el unknown
- 1984-05-08 SE SE8402467A patent/SE8402467L/en not_active Application Discontinuation
- 1984-05-09 GB GB08411768A patent/GB2139588B/en not_active Expired
- 1984-05-10 JP JP59091969A patent/JPS59216795A/en active Pending
- 1984-05-11 NL NL8401531A patent/NL8401531A/en not_active Application Discontinuation
- 1984-05-11 BE BE0/212921A patent/BE899643A/en not_active IP Right Cessation
- 1984-05-11 ES ES532430A patent/ES8506523A1/en not_active Expired
- 1984-05-11 FR FR8407322A patent/FR2550334B1/en not_active Expired
- 1984-05-11 IT IT48181/84A patent/IT1177721B/en active
- 1984-05-11 FI FI841910A patent/FI74251C/en not_active IP Right Cessation
- 1984-05-14 DE DE3417884A patent/DE3417884A1/en active Granted
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1985
- 1985-03-14 ES ES541246A patent/ES8607158A1/en not_active Expired
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1986
- 1986-03-24 AU AU55067/86A patent/AU5506786A/en not_active Abandoned
- 1986-05-06 GB GB08611002A patent/GB2175264B/en not_active Expired
Also Published As
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|---|---|
| ES532430A0 (en) | 1985-08-01 |
| GB2175264B (en) | 1987-04-15 |
| FR2550334A1 (en) | 1985-02-08 |
| FR2550334B1 (en) | 1988-04-15 |
| AU2668784A (en) | 1984-11-15 |
| SE8402467L (en) | 1984-11-14 |
| FI841910A0 (en) | 1984-05-11 |
| GB2139588B (en) | 1987-04-15 |
| FI841910A (en) | 1984-11-14 |
| GR82062B (en) | 1984-12-13 |
| IL71348A (en) | 1989-09-10 |
| FI74251B (en) | 1987-09-30 |
| GB2175264A (en) | 1986-11-26 |
| GB8611002D0 (en) | 1986-06-11 |
| AU5506786A (en) | 1986-08-14 |
| AU548709B2 (en) | 1986-01-02 |
| DE3417884C2 (en) | 1990-04-19 |
| FI74251C (en) | 1988-01-11 |
| ES8607158A1 (en) | 1986-05-16 |
| IT8448181A0 (en) | 1984-05-11 |
| NL8401531A (en) | 1984-12-03 |
| SE8402467D0 (en) | 1984-05-08 |
| ES8506523A1 (en) | 1985-08-01 |
| DE3417884A1 (en) | 1984-12-13 |
| JPS59216795A (en) | 1984-12-06 |
| GB2139588A (en) | 1984-11-14 |
| IT1177721B (en) | 1987-08-26 |
| CH660156A5 (en) | 1987-03-31 |
| ES541246A0 (en) | 1986-05-16 |
| GB8411768D0 (en) | 1984-06-13 |
| BE899643A (en) | 1984-11-12 |
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| Date | Code | Title | Description |
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| MKEX | Expiry |