A ram cannon (1) has an extendable barrel (2) slidably disposed over a starter cannon barrel (7). Such an extendable barrel is fully retractable during transport of the cannon and extendable at the time of firing. The barrel is also partially extendable, thereby providing a means to vary the muzzle velocity of a projectile (6) without varying the ratio of the fuel to the oxidizer in the propellant mixture. Utilizing an extendable barrel allows adapting a ram cannon to mobile artillery weapons, providing ease in transport, setup and firing, with a precise and rapid range adjustment capability.

Extendable ram cannon

A supersonic combustion ram cannon (1) includes a conical projectile (8) with a flat base (9) which produces a subsonic wake (12) as it flies through a barrel (2). The projectile is configured to avoid a normal shock, relying instead on supersonic compression, combustion and gas expansion. The supersonic combustion of a fuel-oxidizer mixture around the tail of the subsonic wake, pressurizes the wake and drives the projectile forward. By utilizing wake stabilized supersonic combustion, the compression and combustion pressures can be matched to the limiting barrel working pressure, thereby providing for optimum thrust and maximum projectile acceleration.

Wake stabilized supersonic combustion ram cannon

This invention is an apparatus and method for determining a set of instantaneous values of optimum flight path for a gliding vehicle at any time t, by determining, at each time t, altitude and position information associated with the vehicle, and wind profile information as a function of the altitude of the vehicle; determining, at each time t, the effective glide slope ratio of the vehicle as a function of the altitude of the vehicle, and then integrating the effective glide slope ratio, at each time t, from the destination point toward the current position and altitude of the vehicle. The invention also contemplates converting such time-dependent value of optimum flight path into a set of control commands for control surface actuators on the vehicle.

Energy management system for a gliding vehicle

The flight vehicle includes an elongated central body having a central axis defined therein and a circumference A plurality of elongated portions are positioned about the central body A plurality of airbreathing engines are axisymetrically positioned about the central axis of the central body and between the respective elongated portions Each flowpath includes a forebody, an inlet, an isolator duct, a combustor, a nozzle, and a mechanism for injecting fuel into the combustor The forebody externally compresses the air flow The inlet is downstream of the forebody to capture air flow The isolator duct is downstream of the inlet to further reduce velocity of the air flow The combustor is downstream of the isolator duct and finally, the nozzle is downstream of the combustor The fuel/air mixture is burned in the combustor and expanded in the nozzle for providing thrust A control mechanism is positioned about the central body for providing control of the flight vehicle The axisymetric relationship of the engines relative to the central body provides balanced forces in flight and simplifies the integration of the present invention into guns and launch tubes

Airbreathing propulsion assisted flight vehicle

A low-drag supersonic tubular projectile with self-contained thrust augmetion and capable of simultaneous dual internal air flows. One is a centrally located supersonic flow for providing low-drag characteristics, and the other a subsonic flow annularly arranged about the supersonic flow path, comprising a ramjet structure with solid fuel for deriving thrust augmentation enabling the projectile to achieve a terminal velocity which is substantially the same as or exceeding muzzle velocity.

Supersonic, low-drag, solid fuel ramjet tubular projectile

A gun-launched ramjet projectile follows a classical vacuum ballistic trajectory by maintaining a thrust-drag balance. The thrust of the ramjet is varied by an air door which bleeds air from the duct that leads from the supersonic diffuser at the front of the projectile to the combustion chamber. The control system for the air door includes an actuator and a pair of accelerometers, the output of which is integrated to provide an indication of velocity. The first accelerometer operates during the launching of the projectile in the gun to measure the launch velocity. A second, and more sensitive, accelerometer measures in-flight velocity changes due to atmospheric conditions. Both of the measured velocities are compared with prerecorded standards and error signals are derived representing any velocity deviations. These error signals are combined and then used to drive the air doors which varies the thrust of the ramjet so that it follows the classical vacuum ballistic trajectory.

Gun-launched variable thrust ramjet projectile

Staustrahltriebwerk-geschoss und verfahren, das dieses einer ballistischen flugbahn folgen laesst

L'INVENTION CONCERNE UN EGALISATEUR DE SOUFFLE POUR UN PROJECTILE A STATOREACTEUR TIRE PAR UN CANON. PLUSIEURS ENCOCHES 32 SONT PRATIQUEES DANS UN ORGANE ANNULAIRE 22, CES ENCOCHES AYANT UNE SURFACE DETERMINEE AVEC PRECISION POUR DEBOUCHER DANS LE VOLUME ANNULAIRE ENTOURANT L'ENVELOPPE D'UN MOTEUR THERMIQUE. LE RAPPORT ENTRE LA SURFACE DES ENCOCHES 32 ET LA SURFACE DE LA GORGE DE LA TUYERE DU MOTEUR THERMIQUE EST EGAL AU RAPPORT ENTRE LE VOLUME ANNULAIRE ENTOURANT LE LOGEMENT DU MOTEUR THERMIQUE ET LA CAVITE INTERNE DE CE DERNIER. L'INVENTION EST UTILISEE POUR EQUILIBRER LA PRESSION S'EXERCANT EN TRAVERS DU LOGEMENT EXTERIEUR DU MOTEUR THERMIQUE D'UN PROJECTILE LANCE PAR UN CANON.

Egalisateur de souffle pour un projectile a statoreacteur tire par un canon

L'INVENTION CONCERNE UN PROJECTILE A STATOREACTEUR A POUSSEE VARIABLE ET LANCE PAR UN CANON. ON FAIT VARIER LA POUSSEE D'UN STATOREACTEUR AU MOYEN D'UNE PORTE 38 PURGEANT L'AIR D'UN CONDUIT 18 ALLANT D'UN DIFFUSEUR SUPERSONIQUE PREVU A L'AVANT DU PROJECTILE 10 JUSQU'A UNE CHAMBRE DE COMBUSTION 32. LE SYSTEME DE CONTROLE DES PORTES 38 COMPREND UN ORGANE DE COMMANDE ET DEUX ACCELEROMETRES DONT LES SORTIES SONT INTEGREES POUR FOURNIR UNE INDICATION DE VITESSE. LE PREMIER ACCELEROMETRE MESURE LA VITESSE AU LANCEMENT, TANDIS QUE LE SECOND, PLUS SENSIBLE, MESURE LES CHANGEMENTS DE VITESSE EN VOL. L'INVENTION EST UTILISEE POUR IMPRIMER, A UN PROJECTILE A STATOREACTEUR LANCE PAR UN CANON, UNE TRAJECTOIRE BALLISTIQUE CLASSIQUE DANS LE VIDE EN MAINTENANT UN EQUILIBRE POUSSEETRAINEE.

John A Simpson

Papers

Gun-launched variable thrust ramjet projectile

Staustrahltriebwerk-geschoss und verfahren, das dieses einer ballistischen flugbahn folgen laesst

Egalisateur de souffle pour un projectile a statoreacteur tire par un canon

Projectile a statoreacteur a poussee variable et lance par un canon