# Patent

## Title
Systems and methods for detecting and managing the unauthorized use of an unmanned aircraft

## Abstract

A method for policing and managing the operation of a flying, unmanned aircraft in the event of usurpation of control of, malfunction of, or ill-intentioned use of, this aircraft includes the steps of (a) detecting inappropriate operation of the aircraft; (b) transmitting a takeover command to the aircraft to interrupt control of the operation of this aircraft by a first pilot and relinquish control of the aircraft to a second pilot; and (c) transmitting control commands to the aircraft to control its operation by the second pilot, until the need for alternate pilot control of the aircraft has ended or until the aircraft has landed safely.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims priority from provisional application No. 60/842,600 filed Sep. 6, 2006. This application also incorporates by reference U.S. Pat. No. 6,917,863 and each of U.S. patent application Ser. Nos. 10/919,169, 11/373,712, 11/385,270 and 11/388,311.
This application is a continuation of U.S. patent application Ser. No. 11/899,827 filed Sep. 6, 2007 (now U.S. Pat. No. 7,835,824 issued Nov. 16, 2010).


BACKGROUND OF THE INVENTION
The present invention concerns a method and apparatus for “policing” unmanned aircraft, such as “umanned aerial vehicles” (UAs) and “unmanned aerial systems” (UASs). The invention is specifically directed to the problems posed by (1) a usurpation of control of an unmanned aircraft by an unauthorized third party, (2) the operation of a malfunctioning unmanned aircraft, and/or (3) the ill-intentioned use of an unmanned aircraft thus posing a danger to person and/or property.
SUMMARY OF THE INVENTION
The systems and methods described herein are intended to prevent the use of unmanned aircraft, e.g. UAs and UASs, hereinbelow “UA”, for unauthorized and possibly ill-intentioned purposes.
The approaches to such prevention include:

    A) Approach #1: Failure to provide a unique identification or password on request makes the UA subject to destruction.
    This approach requires:
    
        1) that all UA have a unique identification, “UI”, consisting of digits, numbers, both or any reproducible information carrying identifier; and
        2) that such identification is either permanently unalterable, or alterable only by an authorized person or entity; and
        3) that such identification must be able to be presented at any time that an authorized person or entity requests;
    
    
    The UI may be either:
    
        1) supplied to the UA at the time of aircraft manufacture, or some later time substantially prior to takeoff;
        2) supplied to the UA immediately prior to takeoff. Such pre-takeoff UI supply approaches parallel the encryption key supply approaches described in U.S. Pat. No. 6,917,863, and include generation of the UI:
        
            a) onboard the UA;
            b) from a remote control center “RCC”; or
            c) from a freestanding UI generation device; or
        
        
        3) both: In this case the UI is supplied at some early instance and a password, “PW”, is supplied immediately prior to takeoff. The password may have the same three possible sources as the UI.
    
    


A request for UI or PW presentation may be made at the time of takeoff, or at any time during a UA flight. If there is either no response or an incorrect response, corrective actions include:

    
    
        1) dispatch an interceptor aircraft, “IAC”, which may:
        
            a) further/better identify the UA; and/or
            b) determine that the UA flight should be terminated.
        
        
        If flight termination is selected, IAC options include:
        
            a) disable or shoot down the UA using a weapon system aboard the IAC; or
        
        
        b) activate a self-destruct system—if included in the UA design [discussed hereinbelow]; and
    
    


2) activate a self-destruct system—if included—from the RCC.

    B) Approach #2: Failure to comply with a pre-registered flight plan makes the UA subject to destruction.

In this approach, the UA is required to file a flight plan prior to takeoff. If the flight plan is unacceptable, takeoff is unauthorized, and any of the means for aircraft destruction or incapacitation discussed hereinabove and hereinbelow may be enacted.

    Methods of monitoring compliance with the flight plan during flight include:
    
        1) Equipment onboard the UA, continually compares the UA position as derived from GPS data or other aircraft locating means as is known in the art, (and the UA velocity vector) with the expected one, based on the flight plan. Any significant deviation from the flight plan is thus detected by onboard equipment and transmitted to an authority at a RCC, who has the options of further observation, investigation or action as described hereinabove;
        2) The UA reports only a continuous, semi-continuous or intermittent stream of GPS data (or reports it on request). Personnel within the RCC then compare such data with either:
        
            a) the previously filed flight plan;
            b) known no-fly zones; or
            c) both a) and b).

If the position or track of the UA is deemed unsatisfactory, RCC authority options are as stated above.

        
        
        3) Visual or radar sightings of the UA are compared with either:
        
            a) the previously filed flight plan;
            b) known no-fly zones; or
            c) both a) and b).
        
        
    
    


If the position or track of the UA is deemed unsatisfactory, RCC authority options are as stated above. The sighting information is obtained by any of the following “monitoring means”:

    
    
        a) other aircraft, including:
        
            i) passenger, commercial or military aircraft who site the UA incidentally;
            ii) other UA, which are in place to police UA (and other) air traffic;
            iii) an IAC, if dispatched; and
        
        
        b) terrestrial stations, including RCCs and air traffic control installations;

Furthermore, the UA may carry a locator beacon which assists tracking of it and serves a purpose similar to that of visual/radar sightings.

    
    


In a preferred embodiment of the invention, Approach #2 is carried out with a UA with a UI (with or without a PW). (If the UA transmits its location and/or transmits deviations from flight plan, the transmission is meaningless without a UI.) Obviously, remotely controlled destruction requires a UI.
In an alternate embodiment of the invention, an aircraft which does not have a UI, which is detected by any of the aforementioned monitoring means may be requested to present a flight plan. Such request may be transmitted to it by

    
    
        1) an IAC in close proximity, on a recognized/commonly agreed upon frequency allocation; or
        2) a non-local RCC, on such a frequency allocation, in which case coordinates with sufficient precision to identify the UA in question would be used as the identifier.
    
    


Failure to comply with the request for flight plan would result in either:

    
    
        1) destruction of the UA; or
        2) escort of the UA by the IAC until such time as:
        
            a) the UA is no longer deemed to be a threat; or
            b) a decision is made to destroy the UA.
        
        
    
    
    C) Approach #3: Each UA is required to allow itself to be controlled by an alternate pilot, upon the request of the alternate pilot. The alternate pilot, representing a known/safe/recognized/responsible authority can:
    
        1) test whether the UA has such capability; and
        2) if necessary, assume control of the UA.

This approach allows policing of UAs by adding the option of alternate pilot, “Alt-P”, control. The alternate pilot controls the UA by any means of information exchange as is known in the art including radiofrequency, optical, and infrared means.

    
    


The Alt-P first determines whether the aircraft is controllable by the Alt-P. This may be determined in one or more of the following ways:

    
    
        1) The Alt-P may interrogate the UA and determine from it's UI whether the UA is controllable. To do this, the Alt-P may access a database containing the UIs of known controllable UAs.
    
    


2) The Alt-P may send a test signal on a frequency and with modulation and coding format known to be used for UAs. If the UA is a controllable one, the UA sends back a confirmation signal indicating that it is controllable.

    
    
        3) The Alt-P may send a test control signal on a frequency and with modulation and coding format known to be used for UAs. The test control signal includes a flight control command which results in a test motion (e.g. momentarily roll five degrees one way and then momentarily roll five degrees the other way and then return to previous course). The Alt-P confirms that the desired result has occurred by either:
        
            a) visual inspection, if the Alt-P is in the near vicinity of the UA; or
            b) a telemetry signal from the UA, originating from sensors within the UA.
        
        
    
    


Test control signals may control pitch, yaw, throttles, etc.
If the Alt-P deems necessary, the Alt-P may take control of the UA and fly it to an appropriate destination.
If the Alt-P determines that the UA has been modified (e.g. post production, or even post take-off) so that the Alt-P cannot fly the UA in a way that was allowed for in the initial specifications, the Alt-P may take action to cause the destruction of the UA. (If not in visual range of the UW the Alt-P can make such a determination with a UA that has a UI.) If the UA was not designed to be controllable by an Alt-P, the Alt-P will then decide (based on existing regulations concerning controllability of a UA, and based on the actions of the particular UA) whether to allow the current UA flight to continue.
The Alt-P may be located within the vicinity of the UA, or at a greater distance. In parallel to the discussions of remote aircraft control in U.S. Pat. No. 6,917,863 and in U.S. patent application Ser. Nos. 10/919,169 and 11/373,712, the advantage of limiting Alt-P actions to local Alt-Ps is the security means available to a short range communications link (i.e. using methods such as a high output controller transmitter and a low sensitivity UA receiver, and using highly directional transmission/reception means). A short range communications link is therefore much less likely to be accessed by an unauthorized person than is a long range link. The advantage of using a long range link is that it can be accessed immediately, upon the detection of a suspicious UA; the delays implicit in

    
    
        1) sending an IAC; and
        2) awaiting its arrival at the vicinity of the UA

are not encountered.

    
    


UAs which allow Alt-P systems give the UA policing community another option beyond either:

    
    
        1) further observe the UA; or
        2) destroy the UA.
    
    


Alt-P systems may be used with or without UI/PW systems and with or without systems which compare aircraft position and velocity vectors with those called for by the flight plan.
The aforementioned system functions are enabled/facilitated and rendered more secure/robust by sub-systems including:

    
    
        tamper detecting seals;
        write-once-only-memory (e.g. so called PROMs (programmable read-only memories), EPROMs, EEPROMs, etc. as are known in the art, and as are, hereinbelow referred to as “XPROMs”);
        encryption/encoding circuits and techniques;
        destructive means aboard the UA.

These are further discussed hereinbelow.

    
    





BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1, comprising FIGS. 1A and 1B in combination shows a flow diagram of the operation of an algorithm for the policing of UAs.
FIG. 2 shows a block diagram for determining the source of control of a UA.
FIG. 3 shows another block diagram for determining the source of control of a UA.
FIG. 4 shows a system of highly directional transmission between a UA and an aircraft for policing UAs.
FIG. 5 shows another system of highly directional transmission between a UA and an aircraft for policing UAs, which includes a terrestrial station.
FIG. 6 shows a block diagram of apparatus for policing UAs.
FIG. 7 shows a block diagram of apparatus aboard a UA which allows it to be policed.
FIG. 8 shows a block diagram of apparatus aboard a UA which allows the assessment of its response to a policing authority command.
FIG. 9 shows a block diagram of apparatus aboard a UA which allows its destruction, if appropriately commanded.
FIG. 10 shows apparatus to be used by a policing authority, for identifying UAs which may need assessment, because of potential, possible or actual inappropriate behavior by the UA.



DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIG. 1 consists of FIG. 1A and FIG. 1B, and shows an algorithm for policing UAs. The algorithm begins with block 10, an indication of a possibly improper UA. The basis of the impropriety could be:

    a) information provided to a policing authority (PA) from one of many possible sources of security information;
    b) information from a computer (or person who operates the computer), which tracks the position of UAs;
    c) information from a computer (or person who operates the computer), which tracks the flight plans of UAs;
    d) information from a computer (or person who operates the computer), which compares the positions and flight plans of UAs; and
    e) GPS or radar or other sighting information (from a ground-based, sea-based, air-based or space-based observer or observation apparatus, indicating encroachment of a UA into a sensitive space.

“Possible T.O. Trigger” 10 indicates an indication, such as listed hereinabove, for possible takeover (TO) of the UA. The takeover would result in

    a) removal of the UA pilot (first pilot herein) control; and
    b) institution of control by either a local or remote pilot (second pilot) who is part of a PA. In one embodiment of the invention, the first pilot PA checks the identification of the UA, block 12. The check could entail any one of a variety of methods known in the art, including:
    a) interrogating an identifying device aboard the UA; and
    b) observing the exterior of the UA, which may include:


i) identifying alphanumeric or other surface based pattern, using visible light;
ii) using a laser to identify coded paint, as is known in the art.
The interrogation of the identifying device, above, may take place by radiofrequency communication on a channel which has been designated specifically for the purpose of UA identification (ID) and policing. If one or more such channels are allocated, the PA may need to attempt communication on each such channel. The ideal situation would be statutory requirement that every UA (or almost every UA) be outfitted with equipment which allows communication on a known, agreed upon channel, using an agreed upon communication protocol known to at least the PA and the UA operator.
At block 14, the PA determines if the ID is acceptable. Such determination may be based on:


    a) a list, appropriately disseminated, of properly registered UAs; and/or
    b) a list, appropriately disseminated, of UAs which are on a “watch list,” indicating the potential for inappropriate UA behavior.


If the ID is acceptable, block 16, the PA:

    a) may end the communication encounter, in which case the PA options, block 18, would be:


i) ending the observation of this particular UA; or
ii) continuing observation (with some enhancement of the level of surveillance above that of other UAs), with or without escorting the vehicle. If the PA is aboard an aircraft in proximity to the UA, such escorting may begin promptly. If the PA is not in proximity to the UA, escorting may consist of dispatching a chase aircraft which flies to the location of the UA and stays in proximity until there is no longer any need for escort.
If the identification is unsatisfactory, or if—at block 16—the PA chooses not to end the communications encounter with the UA, the PA, block 20, may request one or more of:

    a) a UA flight plan;
    b) the UA GPS history (i.e. a history of each previous location that the UA has been, indicated by space and time coordinates); and
    c) a comparison of the UA flight plan and the GPS history, the comparison indicating whether the UA has complied with its flight plan.


Each of a) b), and c) may be stored in a memory unit within the UA, or stored in a ground based facility that tracks UAs, see hereinbelow.
If the PA finds that the flight plan, the GPS history, and/or the comparison of the two is acceptable, then block 22 leads to 24, at which point the PA may choose to end the communications encounter, with options then per block 18, as discussed hereinabove.
If (a) the flight plan/GPS history analysis yields unsatisfactory results, or is not responded to at block 22: or if (b) at block 24 the PA decides that not enough information has been presented to reach a decision about whether the UA flight should be allowed to continue under the control of the first pilot, then, at block 26, the PA requests communications information from the UA. This information may include one or more of:

    a) the frequency or channel on which the UA transmits telemetry to the UA pilot;
    b) the frequency or channel on which the UA receives commands from the UA pilot;
    c) the system or methodology that the UA and the UA pilot use for channel hopping;
    d) the system or methodology that the UA and the UA pilot use for encoding and decoding exchanged information;
    e) the system or methodology that the UA and the UA pilot use for encrypting and decrypting exchanged information;
    f) passwords, if any; and
    g) any other communication formatting or executing information necessary for the PA pilot to fly the UA.


The step of requesting the communications information may come earlier in the algorithm shown in FIG. 1. It may come between blocks 10 and 12, or it may come immediately before block 20. Furthermore, the request for information may be from another UA or the pilot of another UA.
If the requested information is not supplied, block 28 to block 32, the PA options include:

    a) escorting the UA (with the option of more aggressive action at a later time);
    b) destroying the UA;
    c) requesting instructions from a higher authority; and
    d) attempting communication with the UA; If this leads to establishment of a working communications link, the algorithm proceeds as described hereinbelow for block 34; If this does not lead to a working link, options a), b) and c) remain as choices.


The attempt d) may entail a trial-and-error effort to determine the needed communication parameters, or may entail use of information stored in a database.
The PA may skip to the options listed in block 32 if an unsatisfactory result occurs at the time of either ID checking or the assessment of flight plan and/or GPS history.
If the requested communication information is supplied, block 28 to 30A to 30B (FIG. 1A, and continuing on FIG. 1B) to 34, the PA sends a takeover command to the UA. In one preferred embodiment of the invention, the takeover (TO) command causes

    a) the UA to allow piloting by the PA;
    b) the UA to exclude piloting by the UA pilot (the first pilot); and
    c) the UA to send a confirmation signal that the TO command has been executed. Apparatus which allows for the execution of such a commands is presented hereinbelow.


In other embodiments of the invention:

    a) there may not be a TO confirmation signal;
    b) there may not be a lockout of the first pilot from control; and
    c) there may not be a unique TO command; Rather, specific commands (e.g. move rudder by a specific amount) would be sent to the UA.


Referring again to the embodiment in which a confirmation signal is sent when a TO command is enacted, if the TO confirmation is not received following the transmission of a TO command, block 34 to 36 to 38A to 38B (FIG. 1A) to 32 with options including:
include:


    a) escorting the UA (with the option of more aggressive action at a later time);
    b) destroying the UA;
    c) requesting instructions from a higher authority; and
    d) again transmitting a TO command.


If a TO confirmation signal is received, block 34 leads to 36 and then to 40, at which time the PA may attempt to execute a test maneuver. The test maneuver is the transmission of a command which causes a change in aircraft attitude which may either be directly observed by a local PA (e.g. bank five degrees), or may be detected by apparatus onboard the UA (see below).
The purpose of the maneuver is to attempt to distinguish ill-intentioned UA pilots/vehicles from those with benign intentions; The assumption is that an ill-intentioned UA pilot would be much less likely to comply with a request to allow takeover of the UA by the PA. (Though it may be the case that an ill-intentioned UA pilot would not allow for the transmission of information requested in blocks 12, 20 and 26, such denials are dealt with by the algorithm [and lead to block 32].) It may be that an ill-intentioned pilot would have allowed the transmission of information at blocks 12, 20 and 26 hoping to avoid detection.
If the test maneuver is not executed successfully, block 40 leads to 42, then to 38C and then to 38B (in FIG. 1A), with PA options including:

    a) escorting the UA (with the option of more aggressive action at a later time);
    b) destroying the UA;
    c) requesting instructions from a higher authority; and
    d) again transmitting a test maneuver.


If the test maneuver is successful (indicating that the PA is indeed capable, at this point, of piloting the UA) then block 40 leads to 42, and then to 44 with PA options including:

    a) the PA, now in control of the UA, flying the vehicle to a more secure location;
    b) escorting the UA (with the option of more aggressive action at a later time);
    c) returning control of the vehicle to the first (i.e. UA) pilot;
    d) requesting instructions from a higher authority.


The reasoning behind option c) is that if the first pilot permitted each of the aforementioned steps/requests by the PA, the likelihood of his being an ill-intentioned pilot is substantially decreased, compared to the pre-evaluation likelihood.
FIG. 2 shows a form of apparatus which may be aboard a UA which allows for the aforementioned tasks including the transfer of control from the first pilot to the PA following a TO signal, and the transmission of a TO confirmation. The switching apparatus shown is intended to be viewed schematically; though an “old technology” double-pole-double-throw relay may accomplish the task of switching control from the UA pilot (also referred to herein as “pilot 1”) to the PA (also referred to as “pilot 2”), more sophisticated switching arrangements, including computer hardware and/or software based approaches, are possible and are known in the art.
In the figure, signals to the UA are received by 50, and decoded (and decrypted, as necessary) by 52. Under ordinary circumstances, the UA first pilot control signals 54C pass to the appropriate item to be controlled 58 (e.g. rudder, throttles etc.) via the path 54C to 56E to 56C to 56B to 56A to 58. (The poles in the figure are shown in the other position, i.e. allowing control by the PA pilot.)
When the PA wishes to take control of the aircraft, a switch control signal is sent along the path 50 to 52 to 54A to 56L. Switch control 56L causes the two components of the switch to move to the pilot 2/PA pilot (i.e. the left-most position in the figure). The result is that pilot 1 control signals can no longer pass beyond 56E, and that pilot 2 signals control items 58 along the path 50 to 52 to 54B to 56D to 56C to 56B to 56A to 58. If, at a later time, the PA is satisfied that control of the UA can safely be returned to the first pilot (option 3 in block 44 of FIG. 1B), a switch control signal sent to 54A restores control to the first pilot.
The switch components 56F, 56G, 56H, 56J and 56K allow the PA to know the switch position: Switch position indicator 60 senses which of two positions the switch is in, via 56F-56K, the information is encoded and preferably encrypted at 62 and transmitted to the PA by 64.
An alternate embodiment of the switching arrangement is shown in FIG. 3. FIG. 3 differs from FIG. 2 only in that FIG. 3 contain separate receiver/decoder elements for the pilot #1 signals and for the pilot #2 signals. One way of limiting the chance that an unauthorized person/hacker could usurp the authority of the PA and attempt to obtain control over a UA would be to use one or more of:

    a) high output transmitters for PA control signals;
    b) low sensitivity receivers for PA control signals;
    c) highly directional antennae at each end of the PA-UA communication link;
    d) upwardly oriented UA antennae, to communicate with a PA aircraft located at a higher altitude than the UA (This might require an antenna for UAV-PA communication which is separate than the one for UA-first pilot communications. [The separate antenna is not shown in the figure.]; and
    e) time dependent varying of the orientation of either the PA antenna or the UA antenna (with corresponding adjustments by the PA pilot to compensate for such orientation changes). In addition, the aforementioned unauthorized controller exclusion would employ encoding and encryption techniques as are known in the art.


Referring again to FIG. 3, first pilot signals are received along the path 70 to 72 to 74. PA pilot signals are received by a low sensitivity receiver 76, decoded by 78, thereby giving rise to pilot #2 (PA pilot) control signals 80 and pilot #2 switch control signals 82. Embodiments of the invention with two receivers (70 and 76) and a single decoder are possible. Embodiments of the invention which share not only a decoder but which also share all but the “front end” of the receiver are possible.
FIG. 4 shows the use of highly directional apparatus aboard the UA 100 and a PA aircraft 114A. Control signals 122 are sent from an airborne remote control center 116 via directional antenna 118A aboard 114A to directional antenna 120. Directional apparatus may also be for transmission from 100 to 114A.
FIG. 5 shows an embodiment of the invention in which an intercepting aircraft 114B acts as a repeater unit, allow a terrestrial (land or sea-based) remote control network 103 to control a UA 100. Signals to the UA traverse the path 103 to 113 to 118B to 128 (signal repeater equipment) to 118A giving rise to signals 122 to 120 to 100. (The reversed sequence pertains to telemetry and other signals from 100 to 103.) Antennae 113 and 118B would be operative to vary their orientation to optimize signal strength based on the positions of 103 and 114B.
FIG. 6 shows apparatus which comprises a preferred embodiment of the PA apparatus for communicating with a UA. The PA inputs commands via input device 140, which are transmitted by 144. The PA receives UA signals via 134 which may be linked directly to display device 138, or to 138 via logic device 136. 136 allows for the comparison, if desired by the PA, of GPS history and intended flight plans. The flight plans may be stored in memory 142 or received at the time that the GPS history is received. 142 may also store a list of potentially problematic UAVs, i.e. UAVs to be watched more carefully than others. 142 may also store flight routines which allow a PA pilot to fly a UA to a specific destination with a minimum of control activity; 140 may input the control signals which allow for these flight routines to go directly to 144, or to go to 144 from 142. 142 may also serve to record all PA actions that issue from 140. The combination of 136 and 142 may act as a flight management computer and/or autopilot for the UA when it is controlled by the PA who provides input via 140.
FIG. 7 shows a system aboard the UA which communicates with that of the system shown in FIG. 6. The system in FIG. 7 contains
receiver 150, which,


    
    
        1) on receipt of a suitable signal, 150 causes identification XPROM 152 (which is either a PROM, an EPROM, an EEPROM or similar write-once-only-memory device as is known in the art) to signal transmitter 154 (and/or causes transmitter 154 to send the UI contained in 152);
        2) on receipt of another type of signal, and of flight plan information, causes the writing of flight plan information into flight plan XPROM 156;
        3) on receipt of another type of signal, causes the transmission of flight plan information from 156 to 154 to the PA;
        4) on receipt of another type of signal, causes the transmission of communications information from XPROM 153 to 154 to the PA;
        5) on receipt of another type of signal, causes the transmission of real-time GPS information from 158 to 154 and then to the UA;
        6) on receipt of another type of signal, causes the transmission of either:
        
            i) GPS history stored in 160, to 154, to the PA;
            ii) a comparison of the GPS history stored in 160 and the flight plan information, to 154, to the PA.
        
        
    
    


160 may be a computer, part of a computer, a microprocessor, part of a microprocessor or a logic device or system of logic devices as is known in the art. GPS or other locator system information may be:

    a) transmitted to a remote control center (RCC);
    b) used as a basis for assessing compliance with the flight plan. The GPS data may be used to generate both the expected UA position and the expected UA velocity.


160 may cause the transmission of:

    a) all “raw data” related to the comparison of GPS data and the flight plan;
    b) only the results of such comparisons that indicate significant deviation from the flight plan.


In a preferred embodiment of the invention, the apparatus consisting of elements 150 through 160 is enclosed within tamper detecting seal (TDS) 162.
FIG. 8 shows apparatus aboard the UA which allows the RCC to determine if a test command sent by it has been received and executed. Not shown in the figure is:

    a) the receiver which receives the command;
    b) the aircraft apparatus which carries out the command; and
    c) the linkage between a) and b).


If and when the command is executed, one of roll detector 200, pitch detector 202 or yaw detector 204 will register a change in sensed input corresponding to which of these was associated with the test command. (Other test commands are possible.) The output of these detectors is transmitted at 206. In a preferred embodiment of the invention, the transmission is accompanied by a UI from XPROM 208. In a preferred embodiment of the invention, the apparatus comprising elements 200-208 is enclosed in TDS 210.
FIG. 9 shows an apparatus which allows remotely triggered destruction of a UA. The apparatus is enclosed in TDS 220. Transmitter 222 confirms the identity of the UA with a UI from 224. In the event that an authorized person determines that it is not appropriate for the UA to continue its flight, and in the event that such authorized person does not wish to or cannot take control of the UA as a second pilot and fly it to an appropriate destination, the authorized person would have the option of destroying or incapacitating the UA using apparatus aboard the UA shown in the figure.
If the authorized person makes a destruct decision, a destruct signal, “DS” is sent. The DS is received by 225, from which, after appropriate decoding and decryption, a destruct signal is generated, indicated by element 226. Four options for executing such destruction are illustrated in the figure:

    a) 228, indicating apparatus for interrupting electrical power distribution to critical elements within the UA;
    b) 230, indicating apparatus for the interruption of fuel flow within the UA;
    c) 232, indicating apparatus for interrupting the linkage to moving aircraft control elements (throttle, rudder, ailerons, flaps, etc.); and
    d) 234, indicating one or more explosive charges carried by the UA, which may be detonated in response to a signal 226.


FIG. 10 shows apparatus with which a remote control center (either terrestrial or airborne) may determine whether UA location and/or UA flight plans are appropriate. Receiver or datalink 240 receives four types of information:

    a) filed flight plans 242;
    b) GPS information 244, transmitted from GPS apparatus aboard UAs;
    c) UA sighting information 246 (e.g. other aircraft reporting on the presence of a particular UA at a particular time and location); and
    d) deviation signals 248 (such as those generated by element 160 in FIG. 7).


Comparison computer microprocessor/logic system 250 compares:

    a) actual UA position information from 244 and 246 with expected UA position information from 242;
    b) actual UA position information with known “no-fly” zones (stored in database 252); and
    c) filed flight plans with no-fly locations.


254, i.e. (A) 248, and (B) the output of 250, indicating any of the three types of aforementioned deviations are displayed by 256. In a preferred embodiment of the invention, the display may also indicate one or more of:

    a) the UI of the deviated UA;
    b) the magnitude of the deviation;
    c) historical information about the flight: i.e. details about the portions of the flight, if any, prior to the deviation;
    d) historical information about the particular UA including:
    
        1) prior flights; and
        2) the owner; and
    
    
    e) enroute weather information for the UA, as a possible explanation for an off-course location.


The airspace may be patrolled for inappropriate UA activity by:

    a) existing patrol networks;
    b) one or many unmanned aircraft for the specific purpose of policing UAs;
    c) one or many manned aircraft whose primary purpose is either passenger/commercial or military, but which may be outfitted with UA policing equipment; and
    d) combinations of a), b) and c).


There has thus been shown and described a novel method and apparatus for managing unauthorized use of an unmanned aircraft which fulfills all the objects and advantages sought therefor. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose the preferred embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention, which is to be limited only by the claims which follow.

## Claims

1. A method of policing and managing the operation of a flying, unmanned, first aircraft in the event of usurpation of control of, malfunction of, or ill-intentioned use of, said first aircraft, said first aircraft being controlled remotely by a first pilot, not present on said first aircraft, said method comprising the steps of:
(a) detecting inappropriate operation of said first aircraft by means of the steps of:
(1) obtaining an identification information of the first aircraft;
(2) checking the identification information of the first aircraft against a database of preregistered identification information; and
(3) determining if the first aircraft is authorized to fly;

(b) if inappropriate operation is detected, transmitting a takeover command to said first aircraft to interrupt control of the operation of said first aircraft by said first pilot currently in control of said first aircraft; and
(c) a second pilot, also not present on said first aircraft, transmitting control commands to said first aircraft to control the operation of said first aircraft, while excluding operation of said first aircraft by said first pilot, until the need for second pilot control of the first aircraft has ended or until said first aircraft has landed safely.

2. The method defined in claim 1, further comprising the initial step of providing a transmission link by and between a first transmitting and receiving device (“first T/R device”) on the first aircraft and a second transmitting and receiving device (“second T/R device”) in a control station separate from said first aircraft thereby permitting communication between said first aircraft and said control station.

3. The method defined in claim 2, wherein said takeover command is transmitted from a first control station which is located on the ground to said first aircraft.

4. The method defined in claim 2, wherein said control commands are transmitted from a second control station which is located on the ground to said first aircraft.

5. The method defined in claim 1, further comprising the initial step of flying a second aircraft to within the vicinity of the first aircraft, thereby permitting visual observation of the first aircraft.

6. The method defined in claim 2, wherein said takeover command is transmitted from a third control station which is located on a third aircraft to said first aircraft via said transmission link.

7. The method defined in claim 2, wherein said control commands are transmitted from a fourth control station which is located on a fourth aircraft to said first aircraft.

8. The method defined in claim 2, wherein said step of detecting inappropriate operation further includes transmitting an interrogation command to said first aircraft and determining whether a response thereto, if any, is satisfactory.

9. The method defined in claim 2, wherein said identification information includes at least one of
(a) the identification number of said first aircraft;
(b) aircraft owner identification information;
(c) aircraft owner contact information;
(d) aircraft pilot identification information; and
(e) aircraft pilot contact information.

10. The method defined in claim 8, wherein said first aircraft includes means including an altimeter and a GPS device for determining information pertaining to a current location in space of said first aircraft, and wherein a satisfactory response to said interrogation command comprises the step of transmitting information to said control station pertaining to said current location which matches the current position of said first aircraft.

11. The method defined in claim 8, wherein said first aircraft further includes a memory in which is stored information pertaining to a current flight plan of the first aircraft, and wherein a satisfactory response to said interrogation command comprises the step of transmitting information pertaining to the flight plan which matches a previously registered flight plan.

12. The method defined in claim 11, wherein said first aircraft includes means including an altimeter and a GPS device for determining information pertaining to a current location in space of said first aircraft, further comprising the step of comparing said information pertaining to said current location of said first aircraft with said information pertaining to the flight plan, and wherein the response to said interrogation command comprises the step of transmitting said information pertaining to the comparison of said location and said flight plan, and transmitting said takeover command if said location does not correspond to the flight plan.

13. The method of claim 8, wherein said interrogation command is a request to provide at least one type of communication information selected from among the group consisting of:
a) at least one of the frequencies for communication with said first aircraft;
b) at least one of the channels for communication with said first aircraft;
c) the format for communication with said first aircraft; and
d) the method of encoding commands transmitted to said first aircraft; and
wherein a satisfactory response is defined as the receipt of said communication information.

14. The method of claim 8, wherein said interrogation command is a command to execute a change in one of the movable surfaces of the first aircraft and wherein an appropriate response is at least one of (i) a movement of a moveable surface of said first aircraft, and (ii) a movement of said first aircraft, in correspondence with a command to execute a change in said moveable surface.

15. The method defined in claim 2, further comprising the step of transmitting data from said first aircraft to said second pilot wherein said data includes information pertaining to the flight of said first aircraft and said control commands are based on said information.

16. The method defined in claim 15, wherein said first aircraft includes means including an altimeter and a GPS device for determining information pertaining to a current location in space of said first aircraft, and wherein said data includes said information pertaining to said location.

17. The method defined in claim 15, wherein said first aircraft includes a video camera and wherein said data includes video information obtained by said first aircraft.

18. The method defined in claim 2, further comprising the step of providing a transmission link by and between a third transmitting and receiving device (“third T/R device”) at said control station and a fourth transmitting and receiving means (“fourth T/R device”) at an additional control station, thereby permitting communication between said control station and said additional control station,
whereby said control station serves as a repeater station for communications between said additional control station and said first aircraft.

19. The method defined in claim 2, wherein said control station comprises a flight control station to enable said second pilot aboard said second aircraft to control said first aircraft.

20. A method of policing and managing the operation of a flying, unmanned, first aircraft in the event of usurpation of control of, malfunction of, or ill-intentioned use of, said first aircraft, said first aircraft being controlled remotely by a first pilot, not present on said first aircraft, said method comprising the steps of:
(a) detecting inappropriate operation of said first aircraft by means of the steps of:
(1) obtaining aircraft flight information pertaining to the first aircraft;
(2) checking said identification information against a database of aircraft flight information; and
(3) determining if the first aircraft is authorized to fly in accordance with said obtained flight information;

(b) if inappropriate operation is detected, transmitting a takeover command to said first aircraft to interrupt control of the operation of said first aircraft by said first pilot currently in control of said first aircraft; and
(c) a second pilot, also not present on said first aircraft, transmitting control commands to said first aircraft to control the operation of said first aircraft, while excluding operation of said first aircraft by said first pilot, until the need for second pilot control of the first aircraft has ended or until said first aircraft has landed safely.

21. The method defined in claim 20, further comprising the initial step of providing a transmission link by and between a first transmitting and receiving device (“first T/R device”) on the first aircraft and a second transmitting and receiving device (“second T/R device”) in a control station separate from said first aircraft thereby permitting communication between said first aircraft and said control station.

22. The method defined in claim 21, wherein said takeover command is transmitted from a first control station which is located on the ground to said first aircraft.

23. The method defined in claim 21, wherein said control commands are transmitted from a second control station which is located on the ground to said first aircraft.

24. The method defined in claim 20, further comprising the initial step of flying a second aircraft to within the vicinity of the first aircraft, thereby permitting visual observation of the first aircraft.

25. The method defined in claim 21, wherein said takeover command is transmitted from a third control station which is located on a third aircraft to said first aircraft via said transmission link.

26. The method defined in claim 21, wherein said control commands are transmitted from a fourth control station which is located on a fourth aircraft to said first aircraft.

27. The method defined in claim 21, wherein said step of detecting inappropriate operation further includes transmitting an interrogation command to said first aircraft and determining whether a response thereto, if any, is satisfactory.

28. The method defined in claim 27, wherein said step (a) further comprises the step of obtaining aircraft identification information, and wherein
(1) said identification information includes at least one of
(a) the identification number of said first aircraft;
(b) aircraft owner identification information;
(c) aircraft owner contact information;
(d) aircraft pilot identification information; and
(e) aircraft pilot contact information, and

(2) a satisfactory response to said interrogation command comprises the step of transmitting information to said control station pertaining to said identification information which matches respective identification information in a database.

29. The method defined in claim 27, wherein said first aircraft includes means including an altimeter and a GPS device for determining aircraft flight information pertaining to a current location in space of said first aircraft, and wherein a satisfactory response to said interrogation command comprises the step of transmitting said aircraft flight information to said control station pertaining to said current location which matches the current position of said first aircraft in a database of aircraft flight positions.

30. The method defined in claim 27, wherein said first aircraft further includes a memory in which is stored aircraft flight information pertaining to a current flight plan of the first aircraft, and wherein a satisfactory response to said interrogation command comprises the step of transmitting said aircraft flight information pertaining to the flight plan which matches a previously registered flight plan in a database of aircraft flight plans.

31. The method defined in claim 30, wherein said first aircraft includes means including an altimeter and a GPS device for determining information pertaining to a current location in space of said first aircraft, further comprising the step of comparing said information pertaining to said current location of said first aircraft with said information pertaining to the flight plan, and wherein the response to said interrogation command comprises the step of transmitting aircraft flight information pertaining to the comparison of said location and said flight plan, and transmitting said takeover command if said location does not correspond to the flight plan.

32. The method of claim 27, wherein said interrogation command is a request to provide at least one type of communication information selected from among the group consisting of:
a) at least one of the frequencies for communication with said first aircraft;
b) at least one of the channels for communication with said first aircraft;
c) the format for communication with said first aircraft; and
d) the method of encoding commands transmitted to said first aircraft; and
wherein a satisfactory response is defined as the receipt of said communication information.

33. The method of claim 27, wherein said interrogation command is a command to execute a change in one of the movable surfaces of the first aircraft and wherein an appropriate response is at least one of (i) a movement of a moveable surface of said first aircraft, and (ii) a movement of said first aircraft, in correspondence with a command to execute a change in said moveable surface.

34. The method defined in claim 21, further comprising the step of transmitting data from said first aircraft to said second pilot wherein said data includes information pertaining to the flight of said first aircraft and said control commands are based on said information.

35. The method defined in claim 34, wherein said first aircraft includes means including an altimeter and a GPS device for determining information pertaining to a current location in space of said first aircraft, and wherein said data includes said information pertaining to said location.

36. The method defined in claim 34, wherein said first aircraft includes a video camera and wherein said data includes video information obtained by said first aircraft.

37. The method defined in claim 21, further comprising the step of providing a transmission link by and between a third transmitting and receiving device (“third T/R device”) at said control station and a fourth transmitting and receiving means (“fourth T/R device”) at an additional control station, thereby permitting communication between said control station and said additional control station,
whereby said control station serves as a repeater station for communications between said additional control station and said first aircraft.

38. An unmanned aircraft, which is remotely controllable from each of a first source of control and a second source of control, said aircraft comprising:
(a) at least one receiving device, for receiving instruction signals from each of said sources of control;
(b) a processor, coupled to said at least one receiving device, for receiving instructions specified by said respective instruction signals and, in response to flight instructions received from either source of control, producing operational control signals for the aircraft, and, in response to control instructions received exclusively from said second source of control, selecting the source of said flight instructions; and
(c) at least one actuator, coupled to said processor, responsive to said operational control signals, for actuating at least one of:
(1) at least one movable control surface of said aircraft, and
(2) at least one throttle, for controlling the fuel supplied to an engine of said aircraft;

wherein:
(i) said processor is operative to receive at least one first flight instruction from said first source of control specifying at least one of:
(1) a first alteration of at least one of said at least one movable control surface, and
(2) a first alteration of at least one of said at least one throttle;

(ii) said processor is operative to receive at least one second flight instruction from said second source of control specifying at least one of:
(1) a second alteration of at least one of said at least one movable control surface, and
(2) a second alteration of at least one of said at least one throttle;

(iii) said processor is operative to receive a first control instruction from said second source of control, specifying the actuation of said at least one movable control surface and said at least one throttle exclusively in accordance with said at least one received first flight instruction; and
(iv) said processor is operative to receive a second control instruction from said second source of control, specifying the actuation of said at least one movable control surface and said at least one throttle exclusively in accordance with said at least one received second flight instruction; and
wherein said processor is operative, in response to said first and second control instructions from said second source of control, to determine which of said first source of control and said second source of control controls the flight operation of the aircraft.

39. The aircraft defined in claim 38, further comprising:
(d) at least one sensing device, coupled to said processor, for sensing aircraft data including at least one of the position of a movable control surface and a throttle of the aircraft and supplying signals to said processor representing said sensed aircraft data; and
(e) a transmitting device, coupled to said processor, for transmitting signals representing said sensed aircraft data.

40. The aircraft defined in claim 38, further comprising:
(d) at least one additional sensing device, coupled to said processor, for sensing additional aircraft data including at least one of:
(1) the altitude of the aircraft,
(2) the latitude and longitude of the aircraft,
(3) the pitch of the aircraft,
(4) the yaw of the aircraft,
(5) the roll of the aircraft,
(6) the air speed of the aircraft,
(7) the ground speed of the aircraft,
(8) the rate of ascent of the aircraft, and
(9) the rate of descent of the aircraft, and supplying signals to said processor representing said sensed additional aircraft data; and

(e) an additional transmitting device, coupled to said processor, for transmitting signals representing said sensed additional aircraft data.

41. A system comprising the apparatus defined in claim 40, and further comprising:
(i) a first remote control unit for providing said at least one first flight instruction, said first unit comprising:
(a) a first transmitting and receiving (T/R) device;
(b) a first input device for manually inputting first flight instructions;
(c) a first display device for displaying information; and
(d) a first processor, coupled to said first T/R device, said first input device, and said first display device, for processing and supplying signals representing said instructions to said first T/R device and for processing and supplying signals received by said first T/R device to said first display device; and

(ii) a second remote control unit for providing said at least one second flight instruction and said first and said second control instruction, said second unit comprising:
(a) a second transmitting and receiving (T/R) device;
(b) a second input device for manually inputting flight instructions and control instructions;
(c) a second display device for displaying information; and
(d) a second processor, coupled to said second T/R device, said second input device, and said second display device, for processing and supplying signals representing said flight and control instructions to said second T/R device and for processing and supplying signals received by said second T/R device to said second display device.

42. The apparatus defined in claim 38, wherein said at least one movable surface includes at least one of:
(a) a flap,
(b) an aileron,
(c) a rudder,
(d) an elevator,
(e) a spoiler, and
(f) landing gear.

43. The apparatus defined in claim 40, further comprising a memory, coupled to said processor, for storing and allowing access to information.

44. The apparatus defined in claim 43, wherein
(a) said information comprises identification information of said aircraft; and
(b) upon receipt of a third control instruction from said second source of control, said processor is operative to cause said additional transmitting device to transmit a signal representing said identification information.

45. The apparatus defined in claim 44, wherein said identification information includes at least one of:
(a) an aircraft identification number,
(b) aircraft pilot identification information,
(c) aircraft owner identification information,
(d) aircraft pilot contact information, and
(e) aircraft owner contact information.

46. The apparatus defined in claim 43, wherein said memory is a write-once-only memory.

47. The apparatus defined in claim 43, wherein said memory is operative to store flight plan information concerning the intended flight activity of said aircraft, including at least one of:
(a) the intended course of the flight of said aircraft,
(b) the waypoints along the route of said intended course,
(c) the intended arrival time for at least one point along said intended course,
(d) the intended ground speed for said flight, and
(e) the intended loitering time at a vicinity along the course of said flight,
wherein:
upon receipt of a fourth control instruction from said second source of control, said processor is operative to cause said additional transmitting device to transmit a signal representing said flight plan information.

48. The apparatus defined in claim 43, wherein said memory is operative to store flight information, concerning the actual flight activity of said aircraft, including at least one of:
(a) the actual course of the flight of said aircraft,
(b) the waypoints along the route of said actual course,
(c) the actual arrival time for at least one point along said actual course,
(d) the actual ground speed for said flight, and
(e) the actual loitering time at a vicinity along the course of said flight
wherein:
upon receipt of a fifth control instruction from said second source of control, said processor is operative to cause said additional transmitting device to transmit a signal representing said flight information.

49. The apparatus defined in claim 47, wherein
(I) said memory is further operative to store flight information, concerning the actual flight activity of said aircraft, including at least one of:
(a) the actual course of the flight of said aircraft,
(b) the waypoints along the route of said actual course,
(c) the actual arrival time for at least one point along said actual course,
(d) the actual ground speed for said flight, and
(e) the actual loitering time at a vicinity along the course of said flight;

(II) said processor is operative to compare at least one of
(a) the actual and the intended courses of the flight of said aircraft,
(b) the waypoints along the route of said actual course with the waypoints along the route of said intended course,
(c) the actual and intended arrival times for at least one point along said actual course,
(d) the actual and intended ground speed for said flight, and
(e) the actual and intended loitering time at a vicinity along the course of said flight; and

(III) upon receipt of a sixth control instruction from said second source of control, said processor is operative to cause said additional transmitting device to transmit at least one signal representing the results of said comparison of said actual flight information with said intended flight plan information.

50. The apparatus defined in claim 43, wherein said memory is operative to store communications information concerning at least one of:
(a) at least one frequency for transmission utilized by said transmitting device,
(b) at least one frequency for receiving utilized by said at least one receiving device,
(c) at least one method of encryption utilized by said transmitting device,
(d) at least one method of decryption utilized by said at least one receiving device,
(e) at least one communications protocol utilized by said transmitting device, and
(f) at least one communications protocol utilized by said at least one receiving device,
wherein,
upon receipt of a communications control instruction from said second source of control, said processor is operative to cause said additional transmitting device to transmit a signal representing said communications information.

51. The apparatus defined in claim 43, wherein said memory, said processor and said transmitting device are surrounded by at least one tamper detecting seal, coupled to said processor, for detecting unauthorized access to at least one of said memory, said processor and said transmitting device, wherein
(a) said at least one seal is further operative to signal said processor upon the breach of said seal; and
(b) said processor is operative to cause said transmitting device to transmit a signal representing the breach of said at least one seal.

52. The system defined in claim 38, wherein
(a) at least one of said actuators is operative to interrupt the fuel supply to said engine;
(b) said at least one receiving device is operative to receive a signal representing an seventh control instruction, and
(c) upon receipt of said seventh control instruction, said processor is operative to cause said at least one actuator to interrupt the fuel supply to said engine;
thereby to allow for the termination of the flight of said aircraft.

53. The system defined in claim 38, wherein said aircraft further comprises self-destruction means, coupled to said processor, for destroying said aircraft, and wherein
(a) said at least one receiving device is operative to receive a signal representing an eighth control instruction, and
(b) upon receipt of eighth control instruction, said processor is operative to activate said self destruction means;
whereby said second source of control causes the destruction of said aircraft.

54. The system defined in claim 41, further comprising a relay unit comprising:
(a) third T/R device, for communication with said second T/R device of said second unit;
(b) a fourth T/R device, for communication with each of said at least one receiving device and said additional transmitting device aboard said aircraft; and
(c) a processor, coupled to each of said third T/R device and said fourth T/R device;
wherein said processor causes
(i) said third T/R device to retransmit information received by said fourth T/R device, and
(ii) said fourth T/R device to retransmit information received by said third T/R device.

55. The system defined in claim 54, wherein said relay unit is aboard a second aircraft in proximity to said aircraft.

56. The system defined in claim 55, wherein the communications between said fourth T/R device and each of (1) said at least one receiving device and (2) said additional transmitting device aboard said aircraft, is highly directional
thereby reduce the likelihood of interception by an unauthorized person.

57. The system defined in claim 41, wherein said second T/R device is aboard a third aircraft in proximity to said aircraft.

58. The system defined in claim 57, wherein the communications between said second T/R device and each of (1) said at least one receiving device and (2) said additional transmitting device aboard said aircraft, is highly directional.

59. The system defined in claim 41, wherein said second remote control unit further comprises a second memory, coupled to said second processor, for storing flight plan information, concerning the intended flight activity of said aircraft, including at least one of:
(a) the intended course of the flight of said aircraft,
(b) the waypoints along the route of said intended course,
(c) the intended arrival time for at least one point along said actual course,
(d) the intended ground speed for said flight, and
(e) the intended loitering time at a vicinity along the course of said flight;
(II) said processor is further operative to compare said stored flight plan information with actual flight information comprising at least one of
(a) the actual and the intended courses of the flight of said aircraft,
(b) the waypoints along the route of said actual course with the waypoints along the route of said intended course,
(c) the actual and intended arrival times for at least one point along said actual course,
(d) the actual and intended ground speed for said flight, and
(e) the actual and intended loitering time at a vicinity along the course of said flight; and
(III) said second processor is further operative to cause said second display device to display a representation of the difference between said flight plan information and said actual flight information;
thereby to display a representation of the deviation of the actual flight of said aircraft from the intended flight of said aircraft.