Abstract: A portable system (20) for testing an electro-optical guidance assembly (22) includes an electro-optical test unit (40) with at least two sources of electromagnetic energy at different wavelengths for selectively illuminating the guidance assembly. The electro-optical test unit (40) is mounted within a frame (56) that can be part of a wheeled cart (50). The system (20) further includes one or more of: an adjustable fixture (84) for supporting a guidance assembly (22) for testing, a processor unit (42) for controlling the electro-optical test unit (40), a power supply unit (44) for providing electrical power to the electro-optical test unit (40) and the guidance assembly (22), and a leak test unit (46) for generating a vacuum in the guidance assembly (22) or for pressurizing the guidance assembly (22) with an inert gas to test for leaks.

Abstract: A gun suitable for games is disclosed for permitting an operator to recognize when a trigger is pulled. A target signal receiver receives a target signal sent from a target for causing the gun to recognize that the gun is opposite the target, and notifies a controller that the target signal receiver has received the target signal. Upon detection of a manipulation by the operator, the controller a forces shooting device to perform a shooting operation, and instructs an information generator to generate recognition information. The shooting device emits an optical bullet formed of a light ray. The recognition information generator drives a solenoid to bring associated members into impact against each other to permit the operator to recognize that the operation has been performed.

Abstract: The present invention comprises a device which is inert and “thermally-equivalent” to actual ordnance. The device can travel with live ordnance and track the propellant temperatures in order to get a more precise propellant temperature for the ordnance. The device comprises a thermally equivalent inert grain instrumented with thermocouples, connected to a data recorder, and packaged in scaled-down ordnance hardware. The hardware is scaled down to enable the device to more easily travel with live munitions.

Abstract: A gauge for measuring the force required to discharge a firearm by pulling its trigger includes a housing and a rod including a trigger hook portion at a distal end thereof for engaging the trigger. A load cell is connected to the housing and to a proximal end of the rod such that the load cell generates an electrical signal in response to forces on the rod as the housing is pulled while the trigger hook portion is engaged with the trigger. The magnitude of the electrical signal is proportional to the forces on the rod. A microcontroller receives the electrical signal and calculates a force value based thereon. The microcontroller also continuously monitors the forces on the rod and identifies a trigger pull value of the firearm as being the maximum force on the rod until pulling on the housing is ceased once the trigger of firearm has released.

Abstract: A device (10) and a method for determining the muzzle velocity (V0) of the projectile (1) upon exiting a weapon barrel (11). The device (10) includes a coil (12), which is positioned around a longitudinal axis (11.1) of the weapon barrel (11) in the region before the exit, and a supply device (15) for impressing a current (I) in the coil (12) to generate a magnetic field (H). The device (10) additionally includes an analysis device (16), which reads off a voltage pulse on the coil (12), induced during the passage of the projectile (1) through the magnetic field of the coil (12). Two predetermined points of the voltage pulse are detected, the time interval between the two points is determined, and the muzzle velocity (V0) of the projectile (1) is calculated from the time interval.

Abstract: A piezoelectric device is assembled from a piezofilm sensor enclosed between two layers of a multilayer board with a printed circuit.

Abstract: A method and apparatus for trapping projectiles so that the projectiles are not damaged is disclosed. An elongated trough is typically filled with alternating layers of a foam substance and a fibrous substance. Alternatively, the trough can be filled with just a foam or fibrous substance. A projectile launcher such as a gun is connected to the trough and a projectile is shot into the filling substance substantially parallel a longitudinal axis of the trough. The trough can be opened and the projectile can be recovered from the filling substance.

Abstract: A time-difference process and apparatus for scoring supersonic aerial projectiles, such as military aircraft air-to-ground strafing projectiles fired at a strafe target, by detecting and measuring the acoustic shock waves propagated by the projectiles. The process and apparatus uses an array of at least six dynamic transducers to independently sample each projectile shock wave and transmit sampled signals to at least one all-purpose digital computer. The time-differences of arrival of the shock waves at each transducer are processed by an iterative algorithm implemented by the computer. The algorithm calculates projectile impact point, projectile velocity and other useful scoring data. The scoring data are used to quantitatively score the number of hits or misses by the strafing projectiles on the strafe target. Scoring data and other projectile data are selectably indicated to the operator by remote display and printout.

Abstract: A gun muffler and a noise abatement system for a large caliber gun having a gun tube include a catcher. The catcher, which is disposed within the pressure vessel for entrapping particulates and for permitting the projectile to pass, includes a plurality of columns adapted for being removably attached within a pressure vessel. The gun muffler includes a transition section fitted around the gun tube and engaging the gun tube for preventing the escape of residual combustion gases caused by the firing of a projectile by the gun. Attached to the transition section is at least one pressure vessel which defines a pressure chamber for containing residual combustion gases and attenuating pressure waves. The noise abatement system includes a horizontal concrete slab and a gun muffler, as that described above, adapted for being mounted on the concrete slab.

Abstract: An explosive excitation device and method of use thereof for exciting a structure during dynamic measurements. The device includes an accelerometer and an explosive charge. The device is attached at one end to the structure to be excited. The explosive charge is mounted between the accelerometer and the target structure. When the explosive charge is ignited, the accelerometer is blown away from the device. Knowing the acceleration, measured by thee accelerometer, and knowing the mass of the accelerometer, the force applied to the target structure can be calculated. The information on the force of input and the resulting motion of the target structure allows calculation of the structure's dynamic characteristics.

Abstract: An apparatus for measuring exit velocity of a round from a muzzle of a gun barrel includes a first optical fiber having a first fiber optic Bragg grating (FBG) circumferentially attached to the gun barrel at the muzzle and a second FBG circumferentially attached to the gun barrel further from the muzzle than the first FBG; a coupler that receives one end of the first optical fiber; a light source connected by a second optical fiber to the coupler for supplying light to the first optical fiber; a third optical fiber comprising an FBG notch filter, the third optical fiber being connected to the coupler to receive light reflected from the first optical fiber; a notch filter mount attached to the gun barrel, the FBG notch filter being disposed in the notch filter mount; a photodetector connected to an end of the third optical fiber; and data processing electronics electrically connected to the photodetector.

Abstract: A method and apparatus for trapping projectiles so that the projectiles are not damaged is disclosed. An elongated trough is typically filled with alternating layers of a foam substance and a fibrous substance. Alternatively, the trough can be filled with just a foam or fibrous substance. A projectile launcher such as a gun is connected to the trough and a projectile is shot into the filling substance substantially parallel a longitudinal axis of the trough. The trough can be opened and the projectile can be recovered from the filling substance.

Abstract: The invention features a modified catch tube component capable of performing the function of the conventional catch tube and the conventional MEM simultaneously. The catch tube will also feature a capability to accept modular units of mass for adjusting the available angular momentum (of the spinning catch tube) as well as to incrementally adjust inertial resistance for controlling post-impact translational motion. The safety and performance enhancements of the modified spinner are achieved by the above mentioned integration of the MEM with the catch tube. This invention will eliminate MEM free flight and prevent excessively soft, or excessively hard projectile impacts. Equipment such as rails and wheel sets are used to assure that the motion of the catch tube is constrained to translation and to rotation. The invention contrasts conventional spinners in that the motion of a conventional catch tube is limited to rotation only and the MEM to translation and rotation.

Abstract: Provided is a modified configuration that permits operation of instrumentation onboard platforms that may experience severe environmental conditions. The instrumentation permits autonomous acquisition of performance data. Acquired data may be recorded for later playback as well as provided to the platform's operator in real time in multiple formats, such as warning lights, digital displays, video, or audio. An application would be for sensor systems used on an automobile to record performance data, providing a warning when routine maintenance is due or a catastrophic failure is imminent. A specific application uses a flight-certified missile launcher pod on an F/A-18 aircraft, as incorporated in the aircraft's wingtip and modified to hold instrumentation conforming, at least in part, to the launcher pod's internal dimensions.

Abstract: A gunsight reticle defines a system of dimensioned indicia spaced at specific separations to improve aiming accuracy of a rifle. The indicia include perpendicularly intersecting center vertical and center horizontal hairlines, and four horizontal range-marker lines disposed at specific angular separations below the horizontal hairline in bisected relationship with the center vertical hairline. Spacing of the range marker lines below the center horizontal hairline is proportional to bullet drop at selected ranges, depending upon ballistic characteristics of bullet used. Relative lengths of said range-marker bars on each side of the central vertical crosshair are proportional to a cross-wind of 10 mph at target range reflected by respective range marker. The method involves employing this reticle to determine distance to target, and using distance thus determined to ascertain a precise aiming point on the reticle.

Abstract: An electronic firing circuit tester (EFCT) that senses and indicates the status of electrical firing circuits for a gun. The EFCT requires no batteries or other maintenance and can display up to four tests of a gun's firing circuit.

Abstract: The invention features a modified catch tube component capable of performing the function of the conventional catch tube and the conventional MEM simultaneously. The catch tube will also feature a capability to accept modular units of mass for adjusting the available angular momentum (of the spinning catch tube) as well as to incrementally adjust inertial resistance for controlling post-impact translational motion. The safety and performance enhancements of the modified spinner are achieved by the above mentioned integration of the MEM with the catch tube. This invention will eliminate MEM free flight and prevent excessively soft, or excessively hard projectile impacts. Equipment such as rails and wheel sets are used to assure that the motion of the catch tube is constrained to translation and to rotation. The invention contrasts conventional spinners in that the motion of a conventional catch tube is limited to rotation only and the MEM to translation and rotation.

Abstract: A test fixture for testing hovering performance of a tailcone of a countermeasure device is disclosed. The tailcone includes a motor and a propeller which is driven by the motor. The test fixture includes an upper support device, a lower support device, at least one cable connected between the upper and lower support devices and a connection device which slidably attaches the tailcone to the at least one cable, thereby restricting movement of the tailcone along the at least one cable. The upper support device is supported above a water-filled tank, the lower support is disposed in the water-filled tank and the hovering capability of the tailcone is tested by operating the tailcone in the tank. The connection device includes a number of extensions affixed to the tailcone. The extensions each include a clasp spaced from the tailcone. The clasps, are slidably joined along the cables, thereby attaching the tailcone to the cables.

Abstract: A device for sensing projectile velocity in an underwater environment is provided. The device includes a plurality of evenly spaced break screen members positioned in a path of the projectile. Each break screen member includes a support member, a pair of transparent sheets spanning the support member, a continuous resistive trace sandwiched between the transparent sheets, and a sensing member correspondingly connected to each resistive trace. The sensing member includes means for outputting a signal responsive to impact of the projectile against the break screen, and a logic arrangement for determining a difference between impact of at two adjacent break screens throughout the run of break screens, thereby determining a velocity of the projectile.

Abstract: An apparatus for measuring velocity of a projectile includes a plurality of break-screens aligned with each other serially and along a line of travel of the projectile, and parallel to each other, and spaced from each other and from a projectile firing device by selected distances. Each break-screen includes a support sheet and an electrically conductive wire mounted on the sheet so as to be interrupted by passage of the projectile through the sheet. A single amplifier is in communication with each of the conductive wires and is adapted to provide an indication as to a change in voltage in each of the break-screens upon passage of the projectile therethrough, and an indication as to time of the passage. A data collection/display apparatus computes therefrom the velocity of the projectile.

Abstract: A method and apparatus for trapping projectiles so that the projectiles are not damaged is disclosed. An elongated trough is typically filled with alternating layers of a foam substance and a fibrous substance. Alternatively, the trough can be filled with just a foam or fibrous substance. A projectile launcher such as a gun is connected to the trough and a projectile is shot into the filling substance substantially parallel a longitudinal axis of the trough. The trough can be opened and the projectile can be recovered from the filling substance.

Abstract: A portable data acquisition system for use in certifying torpedo tube-launched weapons such as a Mark 48/ADCAP, a Tomahawk missile or a Harpoon and the like. The system includes a portable computer, a rugged four slot chassis, a 32 channel multiplexing module, a four channel isolation amplifier with excitation, eight channel isolation amplifier, a custom signal conditioning module, an associated terminal block and interface cables. The system has the unique feature of obtaining live data for quick analysis about the launched weapon using the torpedo tube as opposed to the post launch data for analysis. All the components are housed in a shock resilient and weather-tight container.

Abstract: The present invention provides an peak chamber pressure measuring apparatus 1 for use with a regular firearm 2 using a given ammunition. The apparatus comprises: a piezoelectric accelerometer 3 for generating a recoil acceleration electrical output signal from recoil acceleration of the firearm upon discharge thereof, and provided with releasable mounting means 6 for rigidly securing the accelerometer 3 to the firearm 2 in proximity to its chamber 11. The accelerometer 3 has signal output means 12 coupled to a signal processing means 13. The signal processing means 13 converts said recoil acceleration electrical output signal which is representative of the peak chamber pressure, using a conversion relationship based on the mass of each of the firearm, and the projectile and the propellant components of the ammunition, and the firearm bore diameter, the signal processing means 13 having signal output means for connection to output signal display means 16.

Abstract: A system for sensing projectile velocity and position having a plurality of support members positioned in a path of said projectile. Each support member has an aperture with a resistive trace supported in the aperture. The resistive trace can be separated by the projectile's passage. A sensing circuit is joined to each resistive trace and provides a signal indicating separation of the resistive trace. This signal is provided to a logic circuit which provides a single signal indicating separation of each said resistive trace. A data acquisition system provides an output indicating said projectile velocity and position with respect to time.

Abstract: A sensor is provided for measuring the speed of a moving sports object, for example, a ball such as a baseball or softball. The sensor is operable over a short range and is preferably mounted in close proximity to the path of the moving object. For measuring the speed of a ball, the sensor is preferably mounted on or in a ball glove or is otherwise mounted on the forearm of a person catching or otherwise receiving or interacting with the ball, for example, by wearing the sensor on such person's wrist. The sensor measures the speed, for example, of a ball about to be caught and displays the speed of the ball to the catching player. The sensor of the preferred embodiment utilizes CW Doppler radar in the form of a microwave radio frequency transmitter and receiver that has a single-transistor integrated antenna/oscillator. A simple, low cost unit having a low radiation and low energy consumption transmitter, receiver and signal processor, is provided.

Abstract: A hardened subminiature telemetry and sensor system for a ballistic projectile having a radome, antenna, steel insert, S-band transmitter circuit board, data recorder, sensor or measurement device and battery. The entire assembly is contained in such a way that the assembly can be threaded into the existing tracer well of a kinetic energy projectile.

Abstract: An apparatus for positioning an object in a remote location with a high degree of precision, insuring stability and repeatability for discrete sampling to be taken at intervals between each sampling on the order of years. A preferred embodiment of the present invention positions an optical probe in a propellant bore hole. The present invention measures and records the exact position of an optical probe within the bore hole, so that exact position may be repeated for future measurements to be taken over the lifetime of the system.

Abstract: A weapon discharge safety mechanism is designed in one multiple section piece for use with handguns and in two separate sections for use with rifles. The discharge safety mechanism includes a trigger guard housing with a bottom, first and second sides and an open top, which fits over and covers the trigger guard and trigger area of a firearm such as a pistol or a rifle. The trigger guard housing portion is releasably secured by a retention pin just behind the front of the trigger guard to hold the trigger guard housing portion in place covering the trigger guard. For handguns, an enclosed bullet trap housing is attached to the trigger guard housing portion. For rifles, this housing is separate. The bullet trap housing has a first closed end and a second open end, which fits over the end of a barrel of the gun and extends over the barrel a short distance.

Abstract: An electronic light source which replaces the hazardous tritium light sou used in the existing Muzzle Reference System (MRS) found on the M1 Series of tanks. The MRS is mounted near the muzzle end of the gun (opposite the breech) and is used by tank gunness to measure gun deflection for calibration of the tank's fire control computer to optimize accuracy. The electronic light source is an LED which is activated by the pulses from a microcontroller based on the input received from a small, low power, omnidirectional motion sensor which detects the movement of the tank mounted on the tank. In the current implementation, the motion sensor comprises a conductive rolling sphere in a cylindrical chamber having a conductive wall with one electrical pole and end plates electrically insulated from the conductive wall and having the other electrical pole such that movement of the element caused by movement of the cylinder will generate intermittent electrical contact between one end plate and the cylinder wall.

Abstract: A test system and a method for testing the final stages of a submarine wen fire control system so as to obtain a complete end-to-end test of the submarine weapon fire control system. The test system includes a launchable test vehicle that can be inserted and launched from a launch tube such as a torpedo launch tube. The test vehicle is the same size and shape as standard launchable vehicles of the type to be tested and preferably includes actual fleet replacement standard components. The test vehicle includes a data recorder that passively records a plurality of signals including power related signals, power crossover signals, preset information, launch sequence information, processor record data, and the like. The test system also includes a data extractor that is used to extract data from the test vehicle in between launches from subsequent launch tubes. The data extractor connects to an umbilical connection on the test vehicle that is normally broken during each launch.

Abstract: Apparatus for measuring projectile muzzle velocity with an accuracy of .+-.0.1% is mounted in an easily portable muzzle attachment. It operates in the following manner. A washer shaped permanent magnet is positioned on a projectile body. A position sensor containing two inductive coils is located inside the muzzle. When the projectile is fired, the magnet mounted on the projectile passes through the inductive coils, inducing a voltage in each coil. Each voltage is amplified and then fed into hysteresis and zero crossing comparators corresponding to each inductive coil. The zero crossing comparator detects when the induced voltage crosses zero. The hysteresis comparator will gate out any noise induced zero crossings. The two zero crossings are used to start and stop a digital counter which generates a velocity count signal that corresponds to the velocity of the projectile. Further noise interference rejection is obtained by encasing the muzzle extension in a magnetic metal.

Abstract: A front loading weapon includes a barrel for firing ammunition therefrom; a breechblock arranged at a rear terminal portion of the barrel; a firing pin carried by the breechblock; and an apparatus for monitoring load conditions of the barrel. The apparatus includes a body sound sensor mounted on the weapon and emitting a first signal representing body oscillations of the weapon; an electronic evaluating device connected to an output of the sensor for emitting a second signal characteristic of an impacting of a cartridge on a region of the breechblock upon loading the cartridge into the barrel; and a warning device connected to the electronic evaluating device for being actuated by the second signal.

Abstract: An archery teaching aid is provided including a shooting area. A first camera is mounted to a top wall of the shooting area which is capable of viewing and recording an arrow passing thereby. A second camera is mounted to a side of the shooting area. The second camera is capable of viewing and recording a user and the arrow situated adjacent thereto. Finally, a control mechanism is provided having a display. The computer is adapted for playing back the recordings of the user during use of a bow and further of a top and side view of the arrow during flight.

Abstract: Peak pressure of a shock wave can be measured by a plurality of frangible crospheres of known fracture pressures. The microspheres are sized to be surrounded by the shock wave as the shock wave travels thereby. The microspheres remaining intact after the shock wave passes provide a measure of peak pressure.

Abstract: A weapon includes a barrel for firing ammunition therefrom; and an apparatus for monitoring firing stresses of the barrel. The apparatus includes a body sound sensor mounted on the weapon and emitting a first signal representing body oscillations of the weapon upon firing; and an electronic evaluating device connected to an output of the sensor. The electronic evaluating device includes a comparator for comparing measuring signals, representing the first signals, with reference signals representing different charges and for emitting second signals representing results of the comparison; and a non-volatile memory operatively connected to the comparator for additively receiving the second signals and for releasing, on demand, the number of firings and information on an accumulated firing stress of the barrel.

Abstract: There is provided a velocity measuring system contained on-board a projectile. The velocity is determined by a microprocessor on-board said projectile that bases the computation on a measurement of the time required for the projectile to pass two fixed points along the gun barrel. The fixed points may be passive signal sources that do not require an external power supply. A high degree of velocity accuracy is achieved because the microprocessor calculation need not be completed during the projectile's traversal of the gun barrel.

Abstract: A projectile grenade launching system tester, comprising a battery, a fem jack to receive voltage from a grenade launcher, a plurality of operational amplifiers to receive constant current from the battery and to receive firing voltage from the grenade launcher through the female jack, a plurality of opto couplers to complete circuits should the voltage from the grenade launcher be greater than 0.5 volts, a plurality of light emitting diodes to indicate by lighting that greater than 0.5 volts is being received and a push button switch to open the circuit and permit resetting of the tester.

Abstract: A system useful in boresight calibration of a launch cell is provided. The aunch cell has a central longitudinal axis coincident with a central longitudinal axis of a projectile that it would support. The launch cell terminates at either end thereof in a door where each door is provided with a hole through which the projectile can pass. The center of the hole is coincident with the central longitudinal axis of the launch cell. The present invention positions a boresight calibration tool relative to the central longitudinal axis of the launch cell. An open-ended first tube is sized for engagement in the hole. The first tube terminates at a first end thereof in a flange that abuts the door when the first tube is inserted into the hole from one side thereof. An open-ended second tube is sized for engagement in the hole from the other side thereof. The second tube terminates at a first end in a flange that is adjacent the door when the second tube is inserted into the hole.

Abstract: A mechanism for determining the presence of a round of ammunition within a firearm by measuring the resistance across the round upon passing a test current through electrodes positioned to contact ammunition, and optionally means for determining the viability of the ammunition.

Abstract: A test assembly for testing an underwater gun in a tank of liquid includes or disposition in the tank in the liquid, a mount for accepting and retaining the gun to be tested, a plurality of baffle plates, each having an aperture therethrough for alignment with a muzzle portion of the gun, a plurality of witness screens for alignment with the gun muzzle portion, a plurality of motion detection sensors for alignment with the apertures of the baffle plates, and a bullet receptacle for alignment with the gun muzzle portion for receiving a bullet fired from the gun. The invention further contemplates a method for testing underwater guns, utilizing the above assembly.

Abstract: A torpedo is provided in a static test fixture where the engine, normally iven by the combustion of otto fuel is driven from a land based source of superheated steam. The torpedo's otto fuel engine is operated on steam and the need for a combustor and other fuel related components is eliminated. Such components are replaced by a steam line and a steam adapter. The torpedo's fuel tank is replaced with an extender section where the steam supply is connected and fed to the steam adapter. The need for storing combustible fuel and oxidizer agents on site is eliminated. The usual support and safety equipment required for handling of otto fuel and explosive devices are also eliminated.

Abstract: A device for measuring the entire profile of a firearm's trigger performance. This device may be either hand held or permanently mounted. The device may be connected to a sensor for sensing strike of the firing pin and connected to a computer for graphically and numerically displaying data relating to the firearm's performance. The device is capable of calculating key firearm performance parameters, including lock time and roughness of the trigger profile.

Abstract: A torpedo is provided in a static test fixture where the engine, normally iven by the combustion of otto fuel is driven from a land based source of superheated steam. The torpedo's otto fuel engine is operated on steam and the need for a combustor and other fuel related components is eliminated. Such components are replaced by a steam line and a steam adapter. The torpedo's fuel tank is replaced with an extender section where the steam supply is connected and fed to the steam adapter. The need for storing combustible fuel and oxidizer agents on site is eliminated. The usual support and safety equipment required for handling of otto fuel and explosive devices are also eliminated.

Abstract: A projectile testing system and method is used to assess the projectile fht and test the accuracy of a projectile launcher and projectile in both controlled and uncontrolled underwater environments. The projectile testing system includes a penetrable member that is positioned substantially orthogonal to an expected flight path of the projectile. The penetrable member intercepts the projectile, forming a penetration in the penetrable member. The location of the penetration is used to determine the actual flight path of the projectile. The penetrable member further includes side support members that help keep the penetrable member taut. In an underwater environment, flotation members and anchor members are coupled to the penetrable member, to hold or support the penetrable member taut. The projectile testing system can also include multiple penetrable members positioned consecutively to provide a more accurate assessment of the actual flight path of a projectile.

Abstract: Portable equipment for immobilizing personal firearms characterized by an articulation connecting the baseplate to the rail, and comprising an intermediate part rotatingly connected to the baseplate about axis (XX) by a coupling element. The intermediate portion forces the rail onto its contact surface by means of a tilting member. The freely mounted connecting element is connected to the intermediate part by a pivot axis. The tilting member including a head inserted into the rail and a slide integral with the head and the intermediate part.

Abstract: An ammunition propellant temperature measuring assembly comprising a first emperature measuring device for determining at least two surface temperatures of a round of ammunition and for transmitting a first signal indicative of the surface temperature, a second temperature measuring device for determining ambient temperature in a storage area for the ammunition and for transmitting a second signal indicative of the ambient temperature, and computer apparatus for receiving the first and second signals and a temperature profile for the ammunition, and adapted to compute therefrom a propellant temperature of the round.

Abstract: A noise abatement system for a large caliber gun includes a gun muffler and a projectile stop, both of which are mounted on a concrete slab. The gun muffler can be coupled at an end to a gun tube of the gun and serves to attenuate pressure waves caused by the firing of a projectile by the gun. The projectile stop is longitudinally aligned with the gun muffler and serves to selectively stop projectiles fired by the gun and to selectively permit projectiles to pass. The projectile stop preferably has an opened first end closest to the gun muffler and a second end to which a door is mounted. When it is desired to aim for a target beyond the projectile stop, the doors are opened to permit the projectile to pass through the projectile stop unhindered. When the projectile stop is used to stop projectiles, the doors are closed and the projectile stop is filled with a particulate material, such as sand.

Abstract: A source of a high speed missile is determined by detecting the shock wave generated by the passage of the missile using a plurality of blast gauges and using the amplitude and direction information from the gauges to calculate the azimuth angle of the track of the missile, the elevation of the track and the miss distance from the location of the gauges. The amplitude and direction information can also be used to calculate the velocity of the missile on at least one point along its track. The apparatus for comprises a plurality of blast gauges arranged to receive shock waves generated by the missile at different locations, a computer arranged to receive amplitude and direction data from the gauges and to perform the necessary calculations and display units for presenting the calculated information. Each blast gauge comprises a spherical fairing containing four pressure sensors whose positions on the surface of the sphere form the apices of a tetrahedron.

Abstract: An ammunition temperature emulating system is provided for use in a tank ch carries ammunition. The temperature of the ammunition (which comprises liquid propellant) is needed to be known for firing accuracy. The temperature is indirectly approximated by measuring the temperature of the wall of the chamber in which the ammunition is stored, using a simulating thermal insert. The system includes a gauge having a sensor bulb, a vacuum bottle having a cavity receiving the sensor bulb and receiving the simulating thermal insert.

Abstract: A weapon station testing system for testing the mission readiness of an aircraft (10) having a plurality of weapon stations including a first weapon station (12a) and a second weapon station (12b) comprises a common electronics module (14) and a plurality of interchangeable mechanical fixtures (16a, 16b). A first interchangeable fixture (16a) is operative for interconnecting the common electronics module (14) with the first weapon station (12a). A second interchangeable fixture (16b) is operative for interconnecting the common electronics module (14) with the second weapon station (12b).